CLA (Conjugated Linoleic Acid) Supplements Review (for
Slimming)
Choose the Best CLA Supplement.
Not All CLA Supplements Contain What You Expect.
Medically reviewed and
edited by Tod Cooperman, M.D. 
Last Updated
: 09/02/2015 | Initially Posted:
06/27/2014
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Table of Contents
What It Is:
CLA (conjugated linoleic
acid) is a polyunsaturated fatty acid found naturally in milk and meat and
produced from safflower and sunflower oils. There are various forms or isomers
of CLA that may perform different functions. The cis-9, trans-11 isomer (also
written as c9, t11) is the predominant type found in milk and meats.
Supplements are typically made from safflower or sunflower oil and have an
equal mixture of cis-9, trans-11 isomer and the trans-10, cis-12 isomer (also
known as t10, c12).
What It Does:
CLA has been shown to
help with slimming by increasing the ratio of muscle to fat, that is,
increasing lean body mass. It has not been conclusively shown to reduce overall
weight (see Review of Weight Loss Supplements for weight
loss products), however, one study of 80 overweight and obese people in China
found that 1.7 grams twice daily of CLA for twelve weeks reduced body fat by 2%
and body weight by 0.9% (Chen, Nutrition 2012).
In this study, serum total cholesterol levels increased by 3.7%, LDL
("bad") cholesterol increased by 3.4%, triglycerides increased by 17%
and HDL ("good") cholesterol decreased by 1.4%, although none of
these changes was statistically significant. Other studies have found that CLA
may lower cholesterol levels but also lower HDL ("good") cholesterol.
The trans-10, cis-12 form appears to be the form most associated with changes
in body composition, but may have potential side effects (see Concerns and Cautions).
In animal and test tube studies, CLA has shown some ability
to inhibit cancer cells. High dietary intake of CLA from high-fat dairy foods
has been associated with a reduction of colorectal cancer by up to 39% in
women, but it is not known if taking CLA supplements has the same association (Larsson, American Journal of
Clinical Nutrition 2005). Preliminary research has also shown higher
intake of CLA from foods, particularly from cheese, to be associated with a
lower risk of developing breast cancer in postmenopausal women (Aro,
Nutrition and Cancer 2000).
Quality Concerns and Tests
Performed:
Neither the FDA nor any
other federal or state agency routinely tests supplements for quality prior to
sale. It is important to know that a product contains the ingredients that it
claims. Too little and you may not get the expected effect and waste your
money. Too much, and you may experience negative effects with certain
ingredients. ConsumerLab.com tested each supplement for its amount of CLA. All
products were also tested for potential contamination with lead, which can
occur in supplements.
What CL Found:
Among the eight CLA
supplements that ConsumerLab.com selected for testing, the following two failed
to be Approved:
·
MusclePharm® CLA Core™ claimed to have
1,000 mg of "CLA Core Blend" per softgel,
but testing showed most of this "blend" was not CLA. In fact, only
38.5% was CLA. Based on the name of the product and a quick glance at the
label, consumers might expect more CLA from this product than it contains. This
is an inherent problem with any product which claims to contain a
"blend" or "formula" rather than specifically listing the
amount of the desired ingredient.
·
Primaforce Max CLA™ contained only
85.8% of its claimed CLA. Instead of providing the listed 800 mg of CLA, each softgel contained only 686.6 mg of CLA.
The six other products
selected for testing by ConsumerLab.com were Approved in testing. In addition,
through ConsumerLab.com's Quality Certification Program,
an additional three CLA supplements were Approved.
None of the CLA products was found to contain unacceptable amounts of lead,
arsenic or cadmium.
Getting CLA for lowest cost:
Comparing the cost to obtain 3,000 mg of CLA from an Approved product,
ConsumerLab.com found that Vitacost Tonalin offered the best value at 45 cents. To get
the same amount of CLA from some other products the cost was more than
triple this amount, as shown in the last column of the table below.
Test Results by Product:
Listed alphabetically
below are the test results for eleven CLA supplements. Eight were selected by
ConsumerLab.com and three others (each denoted below with a CL flask) are
included for having passed the same evaluation through the CL's Quality Certification Program.
Shown in the table are the claimed amounts of CLA and serving sizes recommended
on labels, as well as the results of testing. The full list of ingredients is
available for each product by clicking on the word "Ingredients" in
the first column. Products listed as "Approved" contained their
listed amounts of CLA and met ConsumerLab.com's
quality standards (see Passing Score). The last
column provides price and cost comparison and notable features.
|
RESULTS OF
CONSUMERLAB.COM TESTING OF CLA SUPPLEMENTS |
|||||||
|
Product Name, Serving
Size, and Suggested Daily Dose on Label |
Claimed Amount of CLA
Per Suggested Daily Serving Size |
--TEST RESULTS-- |
Cost for Daily Suggested
Serving on Label |
||||
|
OVERALL RESULTS: |
Contained Labeled
Amount of CLA |
Did Not Exceed
Contamination Limits for Lead, Cadmium and Arsenic |
Disinte-grated Properly |
||||
|
|
4,000 mg Myoleptin™ Safflower Oil |
APPROVED |
|
|
NA |
$0.76 |
|
|
|
1,000 mg |
APPROVED |
|
|
NA |
$0.29 |
|
|
|
2,000 mg |
APPROVED |
|
|
NA |
$0.58 |
|
|
|
3,000 mg Safflower
Seed Oil |
APPROVED |
|
|
NA |
$0.67 |
|
|
|
3,750 mg to 7,500 mg |
APPROVED |
|
|
NA |
$0.83-$1.67 |
|
|
|
3,000 mg to 6,000 mg |
NA3 |
Found 385.1 mg CLA per
softgel (1,155.3 to 2,310.6 mg per daily serving) |
|
NA |
$0.57-$1.13 |
|
|
|
2,250 mg |
APPROVED |
|
|
NA |
$1.10 |
|
|
|
2,340 mg |
APPROVED |
|
|
NA |
$1.26 |
|
|
|
2,400 mg to 4,800 mg |
NOT APPROVED |
Found only 85.8% of
claim (686.6 mg per softgel) |
|
NA |
$0.27-$0.53 |
|
|
|
3,000 mg |
APPROVED |
|
|
NA |
$0.60 |
|
|
|
3,000 mg |
APPROVED |
|
|
NA |
$0.35 |
|
|
|
|||||||
|
Unless otherwise noted, information about the products
listed above is based on the samples purchased by ConsumerLab.com (CL) for this
Product Review. Manufacturers may change ingredients and label information at
any time, so be sure to check labels carefully when evaluating the products
you use or buy. If a product's ingredients differ from what is listed above,
it may not necessarily be of the same quality as what was tested. |
|||||||
|
Copyright ConsumerLab.com, LLC, 2014. All rights reserved.
Not to be reproduced, excerpted, or cited in any fashion without the express
written permission of ConsumerLab.com LLC. |
|||||||
ConsumerTips™:
What to Consider When
Buying:
CLA from Food: CLA is found naturally in milk fat (typically about
5 mg of CLA per gram of fat, but ranging from 2 to 18 mg of CLA per gram of
fat) and meat fat (particularly lamb (6 mg/g), beef (4 mg/g), and veal (2
mg/g). Grass fed "free range" animals will have higher CLA content
than hay/grain fed animals in both milk and meat. Non-fat and low-fat products
will have little CLA. Other food sources of CLA include eggs and mushrooms.
The predominant form of CLA in milk and meats is the cis-9, trans-11 isomer
with much smaller amounts of the trans-10, cis-12 isomer (the form associated
with slimming). Increasing the consumption of fatty food sources to achieve
high intake of CLA is obviously not recommended for slimming purposes as it
adds calories and does not provide much of the trans-10, cis-12 isomer.
CLA From Supplements: CLA in supplements is typically made from
safflower oil. Most supplements use oil that is about 80% CLA with the
remainder consisting of other fatty acids (e.g., palmitic, oleic, stearic, and
linoleic acids). Tonalin and Clarinol
are two common, branded sources of CLA made from safflower oil and both are
typically around 80% CLA (Clarinol also sells a 95%
CLA material).
It is important that you focus on the "conjugated linoleic acid
(CLA)" content in the Supplement Facts ingredient listings. As noted
under What CL Found, a product will sometimes will
list a "blend" or "formula" of which an unspecified amount
will actually be CLA. In addition, some products may list the total amount of
oil, or the amount of one of the branded sources of oil, of which only a
percentage is CLA.
The effectiveness of a CLA supplement may depend on the proportion and amounts
of the forms present. However, at this time, most products do not specify the
ratio CLA forms. In general, supplements with CLA from safflower oil provide an
equal mixture of the trans-10, cis-12 and cis-9, trans-11 forms.
What to Consider When Using:
Studies suggesting improvement in lean body mass used 3 to 4 grams (3,000 to
4,000 milligrams) per day of CLA. One study used 1.7 grams twice daily of Tonalin (50% cis-9, trans-11 and 50% trans-10, cis-12) to
reduce body fat and lower body weight (Chen, Nutrition 2012). Six grams per day was
used to improve insulin levels.
Concerns and Cautions:
·
CLA is generally safe in healthy individuals, however, there
have been reports of it worsening blood sugar control and adversely affecting
the liver, as discussed below. In addition, it may cause side effects: some
people report feeling slightly nauseous after taking CLA or have
gastrointestinal upset or loose stools. These side effects typically are
reduced if it is taken with protein (such as milk), and usually decrease after
about 2 weeks of taking the supplement.
·
Studies using the trans-10, cis-12 isomer of CLA (the form
associated with slimming) have found that it may worsen blood
sugar control in diabetics and in obese people without diabetes. CLA may decrease
insulin sensitivity, creating a pre-diabetic state and lower HDL cholesterol
("good" cholesterol) (Risérus, American
Journal of Clinical Nutrition 2004). However, because most
commercial CLA products contain a mixture of CLA isomers, it is not known if
these products carry this same risk. It may be prudent, for individuals with
metabolic syndrome or diabetes (or at risk for diabetes) not use CLA except
under physician supervision.
·
Three cases of acute hepatitis (inflammation
of the liver) linked to use of CLA supplements have been reported worldwide.
Two of these cases resolved after treatment and discontinuation of CLA
supplementation, while in the third, a liver transplant was required. The most
recently reported case involved a young woman in the U.S. who was hospitalized
for abdominal pain and vomiting after one week of supplementation; her symptoms
cleared and liver function improved seven days after stopping the supplement (Bilal, Case Reports Hepatol 2015).
·
Some animal studies have found the trans-10, cis-12 isomers of
CLA to cause liver enlargement and accumulation of fat in the liver (fatty
liver), which worsened as fat loss increased -- possibly by altering the way
the liver metabolizes fatty acids (Vyas, J Nutr Metab 2012). However, one study which appeared
to monitor liver size reported no change in size nor in distribution of fat in
the liver among overweight men and women who consumed various CLA isomers,
including trans-10, cis-12, at doses up to 3 grams per day for four months (Dilzer, Crit Rev Food Sci Nutr
2012). Nevertheless, out of 16 clinical studies of CLA
supplementation (various forms) in people, six showed increases in the liver
enzymes (GGT, ALT and AST). In these studies, which ranged in length from three
months to 2 years, the amount of time the supplement was used did not appear to
be directly related to the increase in liver enzymes, with some studies
reporting increases in enzymes within several months of use, and others finding
no increases after one year).
·
CLA appears to reduce the fat content of human breast milk. It
is probably prudent for nursing mothers to avoid CLA supplements.
·
Maximum safe dosages of CLA for young children, pregnant women,
or those with severe liver or kidney disease have not been determined.
Information on this site
is provided for informational purposes only. It is not an endorsement of any product
nor is it meant to substitute for the advice provided by physicians or other
healthcare professionals. The information contained herein should not be used
for diagnosing or treating a health problem or disease. Consumers should inform
their healthcare providers of the dietary supplements they take.
Latest Clinical Research Updates for CLA Supplements
9/02/2015
CLA supplements are
popular for slimming, but a recent report of acute hepatitis (liver
inflammation) associated with use of CLA is concerning. Get the details, plus
more about evidence, safety, and our tests of popular products in the CLA Supplements Review >>
2/26/2012
A new study in obese
individuals found that taking a supplement with CLA (conjugated linoleic acid)
for twelve weeks reduced body fat and, to a lesser degree, body weight. But CLA
has other metabolic effects that need to be considered. See the update to
the CLA Supplements Review which has details on dosage and
potential side effects, as well as our product tests. More >>
Related CL Answers (5)
Garcinia Cambogia (HCA) Supplements Review
Find the Best Garcinia Cambogia
Supplement. Choose Carefully! Most Garcinia (HCA) Weight Loss Supplements Lack
Listed Amount of Ingredient .
Medically reviewed and
edited by Tod Cooperman, M.D.
Last Updated: 12/03/2019 | Initially Posted:
11/09/2013
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Supplements Review
Table of Contents
What It Is:
Garcinia cambogia (G. cambogia) is a plant native
to Indonesia. "Garcinia" dietary supplements generally contain
extracts of the dried rind of the fruit of this plant. The compound hydroxycitric acid (HCA), believed to be a key active
Garcinia component for biological effects, naturally comprises up to 30% of the
weight of the dried rind and typically, 50% to 60% of the weight of extracts
made from the dried rind.
What It Does:
The evidence that HCA from Garcinia aids weight loss is mixed. Laboratory
studies of HCA given to animals have demonstrated suppression of food intake
and decreased body weight gain. A possible biochemical basis for HCAs effect
comes from its ability to suppress the production of fatty acids (and fats)
through its inhibition of a cellular enzyme. Although early studies in people
suggested a weight loss benefit, these were small studies with various
weaknesses in their design. The first well-controlled clinical trial found that
a G. cambogia extract (standardized to 50% HCA) failed to
produce significant loss of weight and fat mass beyond that observed with
placebo (Heymsfield, JAMA 1998).
That study involved 135 overweight men and women (many of whom were markedly
obese) who were given 1,000 mg of the extract 30 minutes before each meal (a
total daily dose of 3,000 mg containing 1,500 mg of HCA). During the 12-week
study, participants were put on a high-fiber, low-calorie diet. It has been
suggested that the high-fiber diet may have impaired HCA absorption (Badmaev, JAMA 1999), although this is
speculative.
Two years later, a 12-week study of overweight women found that those
given G. cambogia extract lost more weight than those given
placebo (8.2 lbs vs. 5.3 lbs),
although there was no decrease in appetite (Mattes, Physiol Behav 2000). The participants were put on a
low-calorie diet and encouraged to exercise. They took 800 mg of G.
cambogia extract (50% HCA) 30 to 60 minutes before each meal, for a
daily total of 2,400 mg of extract containing 1,200 mg of HCA. Interestingly, a
small number of men were initially included in this study but their results,
which showed no significant difference from placebo, were excluded from the
overall findings. A smaller, 2-week study in men showed no effect on appetite
or weight loss in those taking 500 mg of HCA three times daily (Kovacs, Int J Obes 2001).
One study which suggested an effect on reducing appetite and food intake but
not a significant reduction in body weight or body mass index (BMI) had
subjects take G. cambogia extract (60% HCA) 1 hour before
lunch and dinner and 2 hours after dinner to prevent snacking in the evening.
In this two-week study, each dose was 500 mg of extract for a daily total of 1,500
mg of extract containing 900 mg of HCA (Westerterp-Plantenga,
Int J Obesity 2002).
More recently, a study of obese women found those who
took 800 mg G. cambogia extract (50% HCA) 30 minutes before
breakfast, lunch and dinner (a total daily dose of 2, 400 mg of extract
containing 1,200 mg HCA) for 2 months while eating a reduced-calorie diet had a
significant reduction in triglyceride levels compared to women who took a
placebo (average reduction of about 23 mg/dL vs. an increase of 4.5 mg/dL,
respectively), but no significant reduction in bodyweight or body mass index (Vasques Phytother Res 2014).
There were also no significant effects on total cholesterol, HDL, LDL, and
insulin levels, nor an effect on levels of leptin (a hormone which regulates
fat storage).
What to make of all this? The evidence suggests that HCA may, in some situations,
modestly help with weight loss, but it is not a sure thing. HCA may be more
effective in women than men and in people who are not markedly obese. As
discussed in the What to Consider When Using section, when
and how you take the supplement may be important in determining its efficacy.
See the Weight Loss Supplements Review for
information about other weight loss ingredients used in supplements.
Quality Concerns and
Tests Performed:
Due to
promotion of Garcinia as a weight loss ingredient in the popular media, many
products are currently on the market and being actively promoted. In ConsumerLab.com's experience, the rapid introduction of new
products to meet a sudden demand for a supplement often results in a high
percentage of products of poor quality. Neither the FDA nor any other federal
or state agency routinely tests Garcinia or other supplements for their
quality. ConsumerLab.com, as part of its mission to independently evaluate
products that affect health, wellness, and nutrition, purchased Garcinia
dietary supplements sold in the U.S. Products were tested to determine how
much G. cambogia extract they contained (based on analyses of
HCA), potential contamination with the heavy metals (lead, cadmium, arsenic,
and mercury), and the ability of products in tablet or caplet form to break
apart (disintegrate) properly. Labels were also checked to be sure they
complied with FDA labeling requirements including listing the correct Garcinia
species and plant part (see How Products Were Evaluated for more
details).
What CL Found:
Among the 13 Garcinia supplements selected for testing by ConsumerLab.com,
only six contained their labeled amounts of HCA. These six are listed as
"Approved" for their quality in the table below, along with four
products which passed the same testing in ConsumerLab.com's
voluntary Quality Certification Program. The seven
products which were "Not Approved" contained just 14% to 81% of the listed
amounts of HCA, as shown in fourth column of the table below. Interestingly,
three products with some of the lowest percentages of their expected HCA were
among four advertised online as the Garcinia extract promoted on the Dr. Oz
show, a claim which was not true as none had been promoted on that show. These
products were Miracle Garcinia Cambogia, Healthy Clip Pure
Garcinia Rapid and Nutritional Sciences Garcinia Lean,
which contained, respectively, only 14.3%, 16.2% and 21.9% of their listed
amounts of HCA. In fact, the suggest daily serving amounts (2 capsules)
of Miracle Garcinia Cambogia and Healthy Clip provided
less than 100 mg of HCA -- less than any other product and far less than used
in any clinical trial, which has typically been 900 to 1,500 mg (see What to Consider When Using). Healthy
Clip was being sold on Amazon.com as
"Dr Oz Garcinia Cambogia Extract" and Garcinia Lean was
promoted in a company press release entitled
"Garcinia Lean, Top Weight Loss Choice After Praised by Dr. Oz, Says
Nutritional Sciences."
Most products were labeled to contain 50% to 60% HCA as a percentage of their
extract, which is consistent with what has been used clinically. However, their
daily suggested serving sizes varied widely, corresponding to daily amounts of
HCA ranging from as little as 250 mg to 3,600 mg per day. It is important to be
aware that, unlike OTC products and prescription medications, where dosing must
be approved by the FDA, dietary supplement companies set their own suggested
serving levels, which may or may not correspond to what has been shown to work.
None of the products were found to be contaminated with heavy metals (lead,
cadmium, arsenic, and mercury) and the one product in tablet form passed
disintegration testing, assuring that the tablet can properly break apart.
Cost:
To help find the lowest cost to obtain HCA, we calculated the cost of getting
1,500 mg of HCA from the products. Among the products Approved in quality
testing, the most economical source of HCA was Puritan's Pride Super Citrimax, from which 1,500 mg of HCA could be obtained
for just 74 cents, followed by NutriGold Garcinia
Cambogia Gold at 76 cents and Vitamin Shoppe Garcinia Cambogia Extract at
83 cents. The most expensive Approved product in terms of obtaining 1,500 mg of
HCA was Pure Health Garcinia Cambogia at $2.08. Among the
products which failed testing, the cost of obtaining 1,500 mg of HCA, based on
how much was actually found, was as much as $21.41 from Miracle
Garcinia Cambogia and $11.39 from Nutritional Sciences
Garcinia Lean.
The bottom line:
You can't trust most Garcinia labels, nor should you rely on the suggested
serving sizes. Products which contained what they claimed and suggested serving
sizes most consistent with clinical studies were Genesis Today Garcinia
Cambogia, or a virtually identical product, Pure Health Garcinia
Cambogia (when taken at the lower end of the suggested serving size 2
pills three times per day, which will provide 1,440 mg of HCA). However, the
daily cost of that dose from either of those products is about $2. You can get
roughly the same dose of HCA and spend less than half that amount using Vitamin
Shoppe Garcinia Cambogia Extract when you take its suggested dose (2
pills) three times a day, preferably about one hour before lunch and dinner and
perhaps a couple of hours before bedtime if you are prone to nighttime
snacking. Many Garcinia products include chromium as an added ingredient, although
the evidence is mixed as to whether chromium helps with weight loss. Black pepper is
also in some products, as it may enhance the bioavailability of ingredients by
inhibiting their breakdown. These and any other added ingredients are listed in
the last column of the table below, with more detail to be found in the Ingredients table.
Test Results by Product:
Listed
alphabetically below are the test results for seventeen Garcinia supplements.
ConsumerLab.com selected 13 products, and four other products (each indicated
with a CL flask) were tested at the request of their manufacturers/distributors
through CL's Quality Certification Program and
are included for having passed testing. Also listed is a product which is very
similar to one that passed testing but is sold under a different brand name.
Shown for each product is the claimed amount of Garcinia extract, the percent
claimed to be HCA, and the serving size recommended on the label. The full list
of ingredients is available for each product by clicking on the word
"Ingredients" in the first column. Products listed as
"Approved" met their label claims for HCA and ConsumerLab.com's
quality criteria (see Passing Score). Be aware that suggested
serving sizes on labels may not reflect an appropriate dosage for your intended
use. Adjustments may be necessary, as discussed above and in the section What to Consider When Using. Cost comparisons
appear in the last column.
|
RESULTS OF CONSUMERLAB.COM TESTING OF GARCINIA SUPPLEMENTS |
||||||
|
Product Name, Serving
Size, Garcinia Extract Per Unit, and Servings Per Day Suggested on Label |
Labeled Daily Amount
of Garcinia Extract and % HCA |
— TEST RESULTS — |
Cost for Daily
Suggested Serving on Label |
|||
|
OVERALL RESULTS: |
Contained Labeled
Amount of HCA |
Did Not Exceed
Contamination Limit for Lead, Cadmium, Arsenic and Mercury |
Dis- |
|||
|
Absolute™ Garcinia Cambogia (500 mg of extract
per capsule, 2 per day) |
1,000 mg Garcinia
extract |
NOT APPROVED |
Found only 21.8% of
claim (130.6 mg daily) |
|
N/A |
$0.50 |
|
Bio Nutrition Garcinia Cambogia (500 mg of
extract per vegetarian capsule, 2 per day) |
1,000 mg Garcinia
extract |
NOT APPROVED |
Found only 81.1% of
claim (405.5 mg daily) |
|
N/A |
$0.34 |
|
Futurebiotics Garcinia Cambogia Extract 500 mg (500 mg of
extract per vegetarian capsule, 1 per day) |
500 mg Garcinia
extract |
APPROVED |
|
|
N/A |
$0.24 |
|
Garcinia Cambogia Select (500 mg of extract
per capsule, 3 per day2) |
1,500 mg Garcinia
extract |
APPROVED |
|
|
N/A |
$0.93 |
|
Garcinia Cambogia XT (500 mg of extract per capsule,
2 per day)6 |
1,000 mg Garcinia
extract |
APPROVED |
|
|
N/A |
$1.11 |
|
Genesis Today™ Garcinia Cambogia (400 mg of
extract per vegetarian capsule, 6 to 12 per day) |
2,400 mg to 4,800 mg
Garcinia extract |
APPROVED |
|
|
N/A |
$1.92-$3.84 |
|
Healthy Clip Pure Garcinia Rapid (500 mg of
extract per capsule, 2 per day) |
1,000 mg Garcinia
extract |
NOT APPROVED |
Found only 16.2% of
claim (96.9 mg daily) |
|
N/A |
$0.50 |
|
Jarrow Formulas® HCActive™
(500 mg of extract per capsule, 6 per day) |
3,000 mg Garcinia
extract |
APPROVED |
|
|
N/A |
$2.00 |
|
Labrada Nutrition Garcinia Cambogia (780 mg of
extract per capsule, 6 per day) (See Update) |
4,680 mg Garcinia
extract |
NOT APPROVED |
Found only 60.2% of
claim (1,690.2 mg daily) |
|
N/A |
$1.20 |
|
Miracle Garcinia Cambogia (500 mg of extract
per capsule, 2 per day)6 |
1,000 mg Garcinia
extract |
NOT APPROVED |
Found only 14.3% of
claim (85.6 mg daily) |
|
N/A |
$1.22 |
|
Molecular Research Labs Pure Garcinia Cambogia
(750 mg of extract per capsule, 2 per day) |
1,500 mg Garcinia
extract |
NOT APPROVED |
Found only 33.5% of
claim (251.4 mg daily) |
|
N/A |
$1.14 |
|
Nature's Plus® Citrimax®
1000 mg (1,000 mg of extract per tablet, 1 per day) |
1,000 mg Garcinia
extract |
APPROVED |
|
|
|
$0.32 |
|
NutriGold® Garcinia Cambogia Gold™ (1,000 mg of extract
per vegetarian capsule, 3 to 6 per day) |
3,000 mg to 6,000 mg
Garcinia extract |
APPROVED |
|
|
NA |
$0.90-$1.80 |
|
Nutritional Sciences™ Garcinia Lean (500 mg of
extract per capsule, 2 per day) |
1,000 mg Garcinia
extract |
NOT APPROVED |
Found only 21.9% of
claim (131.4 mg daily) |
|
N/A |
$1.00 |
|
Pure Health Garcinia Cambogia (400 mg of
extract per vegetarian capsule, 6 to 12 per day) |
2,400 mg to 4,800 mg
Garcinia extract |
APPROVED |
|
|
N/A |
$2.00-$3.99 |
|
Puritan's Pride® Super Citrimax®
(750 mg of extract per capsule, 7 per day)3 |
5,250 mg Garcinia
extract |
APPROVED |
|
|
N/A |
$1.55 |
|
The Vitamin Shoppe® Garcinia Cambogia
Extract |
1,000 mg Garcinia
extract |
APPROVED |
|
|
N/A |
$0.334 |
|
Similar to Approved Products*: |
||||||
|
Vitamin World® Super Citrimax® |
Similar to Puritan's Pride® Super Citrimax®. |
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|
|
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|
Unless otherwise noted, information about the products
listed above is based on the samples purchased by ConsumerLab.com (CL) for
this Product Review. Manufacturers may change ingredients and label
information at any time, so be sure to check labels carefully when evaluating
the products you use or buy. If a product's ingredients differ from what is
listed above, it may not necessarily be of the same quality as what was
tested. |
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|
Copyright ConsumerLab.com, LLC, 2013. All rights reserved.
Not to be reproduced, excerpted, or cited in any fashion without the express
written permission of ConsumerLab.com LLC. |
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ConsumerTips™:
What to
Consider When Buying:
Garcinia cambogia extracts are typically standardized to contain
50% to 60% hydroxycitric acid (HCA or (-)-hydroxycitric acid). The remainder of the extract (40% to 50%
of the total) is composed of carbohydrates and fat from the rind of the Garcinia
cambogia fruit although these are not significant amounts in terms of
calories (3 or 4 calories per pill).
HCA, in its "free" molecular form, is unstable, so ingredient manufacturers
commonly bind it to minerals, such as calcium, potassium, or magnesium, to
stabilize it. Two common branded versions of Garcinia extract are Citrimax® (which is 50% HCA) and SuperCitriMax®
(which is 60% HCA and has also been referred to in clinical studies as Citrimax HCA 600 SGX), both of which bind HCA to calcium
and potassium. Due to the relatively large daily dosing of Garcinia
supplements, these ingredients can be significant sources of minerals. For
example, a daily dose of 4,500 mg of SuperCitrimax,
would be expected to contain 720 mg of potassium and 495 mg calcium. The
company which sells these branded ingredients, InterHealth, claims that the
added calcium/potassium make the HCA more soluble and better absorbed than
other HCA products. However, the research InterHealth
cites (Downs, Mut Res 2005) suggests that even in
this form, the HCA is only partially absorbed, as shown in earlier research (Loe,
Anal Biochem 2001).
Choosing a supplement made with a branded form of HCA might seem to help assure
quality but only two of the three products selected for testing which contained
either SuperCitrimax or Citrimax
(as noted in the table above) passed ConsumerLab.coms
tests -- the Labrada product
contained only 60.2% of its listed HCA.
Garcinia is frequently included as an ingredient in weight loss
"formulas" or "blends" which contain multiple ingredients
but do not list the amount of each. It would seem prudent to avoid these
multi-ingredient formulas or blends for several reasons: It is unlikely they
have been clinically tested; it is best to use single-ingredient supplements
(showing the amount of the ingredient) to determine if an ingredient actually
works for you; and weight loss formula or blend products are more likely than
single ingredient products to contain dangerous, undeclared drug-like
substances or have other problems with their quality (See related Recalls and Warnings of
Garcinia-containing supplements).
What to Consider When Using:
When and how to take it:
A study of Citrimax taken as a liquid showed HCA to
reach maximum levels in the blood 60 to 90 minutes after ingestion, falling
rapidly thereafter (Westerterp-Plantenga,
Int J Obesity 2002). A study of SuperCitrimax
showed maximum levels at 2 hours after ingestion (Loe, Anal Biochem 2001). Consequently, if HCA causes reduced
appetite or is most effective when blood levels are highest, it may be best to
take the extract as much as 1 to 2 hours before eating, rather than the typical
30 to 60 minutes suggested on labels. In addition, research has indicated that
taking Garcinia with a full meal results in significantly lower levels of HCA
than when taken on an empty stomach, underscoring the importance of taking it
well before a meal (Downs, Mutat
Res 2005).
Concerns and Cautions:
Garcinia
has generally been found to be safe, but there are no long-term studies. Some side
effects that have been reported include nausea, GI discomfort, and
headache. Rarely, use of garcinia supplements has been
associated with liver damage and/or liver failure. For example, a
previously healthy 34-year old man with no known risk factors for liver disease
developed liver failure and subsequently required a liver transplant after
consuming two 80 mg capsules of Swanson Premium Brand Garcinia Cambogia
5:1 Extract three times daily before meals for five months (Lunsford, World J Gastroenterol 2016). In
another reported case, a 57-year-old woman developed acute hepatitis
(inflammation of the liver) after consuming 1,400 mg of a "100% pure
Garcinia cambogia fruit rind extract" twice daily for one month. Her liver
enzyme levels returned to normal and the hepatitis resolved within one month of
stopping supplementation; however, her liver enzymes became elevated again six
months later after she began taking the supplement again -- indicating that the
supplement was the likely cause (Sharma, Case Rep Gastrointest
Med 2018). In a third case, a
21-year-old woman developed acute liver failure after taking 1,400 mg of Garcinia
cambogia extract for one month. Her symptoms began to improve seven
days after stopping supplementation and receiving treatment, and they resolved
completely after a little over one month (Yousaf, World J Hepatol 2019).
There is some concern that taking Garcinia along with antidepressants of the
SSRI (serotonin reuptake inhibitor) class may cause serotonin toxicity.
A case has been reported of a 35-year old woman in Oregon who had been taking
20 mg daily of the SSRI escitalopram (Lexapro) for over one year but
approximately one to two months after starting Garcinia, she developed a
tremor, flushing and sweating — symptoms of serotonin toxicity (Lopez, J Med Tox 2014). Her symptoms, when
seen at an emergency room, also included stuttering speech and a rapid
heartbeat. Although the brand of Garcinia was not identified in the report, the
product label listed the following in a 2 capsule serving: G. cambogia (fruit
rind) extract (60% HCA) 1,000 mg, chromium 200 mcg, and small amounts of
potassium and calcium (similar to many products in this Review). She was taking
two capsules three times a day -- for a total daily intake of 3,000 mg of the
extract. Although this one case study is not definitive proof of a cause and
effect relationship, research in rats have shown that Garcinia extract (Super Citrimax) is capable of inhibiting the update of serotonin
in brain cells and a study human subjects showed a 39.8% increase in serum
serotonin concentrations after 8 weeks. There appears to be a delay in the
buildup of serotonin, so that toxicity would not be expected right away but
after several weeks of taking Garcinia along with the SSRI drug, as in the
above case report.
Episodes of mania have been reported
in three adults with bipolar disorder (or a possible
pre-disposition to bipolar disorder) who took Garcinia (1 to 2 capsules daily
-- % HCA and dose not provided) for a period of 1 to 2 months. These included a
50 year old man with bipolar I disorder who had been stable without medication
for six years was hospitalized for mania after taking 1 to 2 pills of Garcinia
every day for two months; a 34 year-old woman with bipolar II disorder who was
taking several medications (aripiprazole, bupropion, topiramate) and developed
irritability, pressured speech, decreased need for sleep, and agitation after
taking Garcinia for 4 to 6 weeks; and a 25 year-old man without a psychiatric
history who was hospitalized for severe mania and bipolar I disorder after
taking Garcinia for daily for 2 months. In each case, the manic episode
resolved after the patients stopped taking Garcinia and received standard
treatment (Hendrickson, Prime Care Companion
CNS Disord 2016).
A three-month study in genetically obese male rats given a range of doses
of Garcinia cambogia extract found it to cause testicular
toxicity and atrophy (shrinkage) at the high doses, but not at lower
doses. The study also showed the extract to suppress fat accumulation, but,
unfortunately, this effect only occurred at the doses which also caused
toxicity (Saito, Food Chem Toxicol 2005).
In terms of body weight, the high doses given to the rats were about twenty to
thirty times as much as normally taken by people, so a similar risk of toxicity
may not exist for people, and has not been reported.
Information on this site
is provided for informational purposes only. It is not an endorsement of any
product nor is it meant to substitute for the advice provided by physicians or
other healthcare professionals. The information contained herein should not be
used for diagnosing or treating a health problem or disease. Consumers should
inform their healthcare providers of the dietary supplements they take.
Latest Clinical Research Updates for Garcinia Cambogia (HCA) Supplements
12/03/2019
Another case of liver
failure associated with the use of Garcinia cambogia has been reported. For
details, see the Concerns and Cautions section
of the Garcinia Cambogia Supplements Review.
8/28/2018
Be aware that Garcinia
cambogia extracts, touted for weight management, may cause liver injury, as
suggested by two recent case reports. See the Concerns and Cautions section
of the Garcinia Cambogia Supplements Review for details.
9/17/2016
There are recent reports
of people experiencing mania when taking Garcinia cambogia (HCA). For details
see the Concerns and Cautions section of the Garcinia Cambogia Supplements
Review >>
9/06/2014
A recent study in obese
women found that taking a Garcinia cambogia extract for two months did not
impact weight -- although it did modestly reduce triglyceride levels. This adds
to an already mixed picture about the effects of Garcinia. Learn more about
this and earlier studies, see our bottom line about Garcinia's efficacy, and
see how popular brands of supplements have fared in our tests in the
updated Garcinia Cambogia (HCA)
Supplements Review >>
Danger Using Antidepressant with Garcinia cambogia
5/31/2014
Taking the popular weight
supplement Garcinia cambogia along with a common
antidepressant may cause toxicity, according to a new report. For more details,
as well as our tests of Garcinia cambogia supplements, see
the Garcinia Cambogia Supplements
Review >> (Also see the CL Answer about supplement interactions with
antidepressants.)
Related CL Answers (2)
Weight Loss Supplements Review (7-Keto DHEA, Forskolin
and Stimulant Blend Supplements)
Choose the Best Weight Loss
Supplement. Be Careful With Weight Loss Supplements — Few Pass Quality Testing
and Safety Review.
Medically reviewed and
edited by Tod Cooperman, M.D.
Last Updated: 03/26/2021 | Initially Posted:
05/24/2019
Recent Reviews
·
Aloe Juices, Gels, and Supplements
Review
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NAD Booster Supplements Review
(NAD+/NADH, Nicotinamide Riboside, and NMN)
·
PQQ (Pyrroloquinoline Quinone)
Supplements Review
Table of Contents
Summary
·
Do weight loss pills work? There isn't overwhelming evidence that
any dietary supplement enables significant, long-term weight loss. However, many
small studies — typically funded by supplement companies -- suggest short-term
weight loss, slimming (reducing fat but not overall weight), and/or appetite
reduction (see What It Does for a summary of the
evidence).
In this Review, CL focused on stimulant blends (which are some of the most
popular weight loss supplements and contain caffeine and/or synephrine), as
well as supplements with 7-keto DHEA or forskolin (from Coleus forskohlii). CL has separately reviewed many other
types of supplements used for weight loss — see the list in What It Is.
·
What did CL find? Laboratory tests and analyses by ConsumerLab revealed potentially dangerous amounts of
caffeine in three products and a potentially dangerous amount of synephrine in
another — twice the amount expected from its label. In addition, one Forskohlii supplement contained less than 5% of its
expected forskolin. All of the 7-keto DHEA supplements contained their claimed
amounts.
Across products, the dose of caffeine ranged from 51.6 mg to 270 mg per serving
in stimulant blends, 7-keto DHEA ranged from 25 mg to 100 mg, and forskolin
ranged from just 1.9 mg to 50 mg. The cost to obtain 100 mg of 7-keto DHEA
ranged from 15 cents to $3.00 and the cost for 25 mg of forskolin ranged from
33 cents to $1.40 -- showing huge opportunity for savings when buying these
products. For details, see What CL Found.
·
Top Picks — Among products Approved in testing, ConsumerLab selected a Top Pick for
7-Keto DHEA and a Top Pick for
Forskolin, with each providing the clinically tested dosage
at relatively low cost. A Top Pick
Stimulant Blend was also chosen that provided a safe
level of caffeine.
·
How much to take and when? Dosage for 7-Keto DHEA is typically 100
mg twice daily and for Forskohlii it is 25 mg of
forskolin (from 250 mg of extract standardized to 10% forskolin) twice daily.
For caffeine, there isn't sufficient research to suggest a dose effective for
weight loss. See the ConsumerTips™ section
for more about dosage and forms.
·
Cautions: Stimulants and forskolin may affect blood pressure and
heart rate and interact with medications. 7-keto DHEA may affect thyroid
levels. (For details, see Concerns and Cautions.)
What It Is:
Many ingredients have
been touted for weight loss. These ingredients include synephrine (from bitter
orange), calcium (see separate Review of Calcium Supplements), chitosan (from
shells of crustaceans), ephedra (an herbal ingredient also
known as ma huang and which contains ephedrine and
other stimulant alkaloids), green tea (see Review of Green Tea), 7-keto
DHEA, hydroxycitric acid (HCA) from the
fruit Garcinia cambogia (see separate Review of Garcinia (HCA)
Supplements), green coffee bean extracts (see
separate Review of Green Coffee Bean
Supplements), hoodia (from the cactus-like
plant Hoodia gordonii — see
separate Hoodia Review), pyruvate and L-carnitine (both
of which are found and made in our bodies), the essential mineral chromium naturally
found in animals, plants, and soil (also see separate Review of Chromium Supplements), raspberry ketones (from red raspberry fruit)
and herbal stimulant blends.
Also, forskolin (from roots of the Coleus forskohlii plant)
and conjugated linoleic acid (CLA) may help with slimming by increasing the
proportion of lean body mass (muscle) to fat (see separate Review of CLA Supplements).
What It Does:
The amount of evidence supporting
the various weight loss ingredients varies, and, for many, is not very strong.
There are also safety concerns regarding the use of some. Below is a summary of
information about several of the most popular ingredients used for weight loss
(see ConsumerTips™ for
more information specifically about the forms, dosage, and safety for 7-keto
DHEA, stimulant brands, and forskolin):
|
Summary of Evidence for Popular Weight Loss
Ingredients |
|||
|
Ingredient Name |
Purported Use |
Evidence |
Safety |
|
7-keto DHEA |
May provide additional weight loss in
overweight people on calorie-reduced diets. Appears to work by increasing metabolism. |
Short-term clinical studies. More research
needed. |
Not well studied in people. |
|
Bitter Orange |
Widely marketed for weight loss when used orally
as a concentrated extract made from the peel. Often found in place of ephedra
in "ephedra-free" products. Many other purported uses. |
Weight loss seen in some animal studies. May
work through increased metabolism. One preliminary study in obese individuals
using 975 mg/day of extract showed weight loss, but product also contained
caffeine (528 mg/day) and St. John's wort. |
Contains a stimulant, synephrine, which may
cause hypertension, increased heart rate and cardiovascular toxicity. Other
compounds in the extract may contribute to the cardiovascular effects (Hansen, Tox and Applied Pharm
2012). Can also cause photosensitivity and can interact with
medications. Should be avoided by persons with hypertension, heart disease,
and narrow-angle glaucoma. Risks may be higher in products with boosted
synephrine levels or when combined with other stimulants such as caffeine or
decongestants. It may also interact with certain medications. The U.S. FDA
has not established limits on use, but Canada has approved the use of up to
only 50 mg per day of p-synephrine alone in healthy adults, and 40 mg per day
or less of p-synephrine when combined with 320 mg per day or less of
caffeine. |
|
Calcium |
May enhance weight loss. |
Increased calcium from dairy products (but not
supplements) is associated with greater weight loss when dieting. |
Generally regarded as safe. |
|
Caffeine/Stimulant Herbal Blends |
Products often claim these stimulant
ingredients "increase metabolism." |
Little evidence, other than when used with
ephedra, which has modest short-term weight loss effect but carries risks. |
Chronic use, especially in large amounts, can
produce tolerance, habituation, psychological dependence, and other
significant adverse effects. Doses of caffeine greater than 250-300 mg per
day have been associated with adverse effects such as tachyarrhythmias and
sleep disturbances. |
|
Caralluma fimbriata |
Appetite suppressant. |
One two-month study, which found 1 gram per
day to suppress appetite and reduce waist circumference, but not
significantly decrease body weight or body fat (Kuriyan, Appetite
2008). |
No long-term safety studies. |
|
Cha de Bugre |
Appetite suppressant. |
No clinical studies. |
No safety studies. |
|
Chitosan |
Promoted as a "fat blocker" to enhance
weight loss. |
Mixed results and no large study. Does not
appear to affect fat excretion. May have small benefit when used as part of
calorie-restricted diet. |
Generally regarded as safe. |
|
Chromium |
May assist in weight loss and improve body
composition (fat/muscle ratio). |
One study found modest weight loss but most
other studies failed to find benefit for weight loss or body composition.
Evidence that it can help some people control blood sugar levels. |
Trivalent (III) form is generally considered
safe when taken at a dose of 200mcg daily or less; reports of some toxicity
at higher amounts (usually over 600 mcg). Hexavalent (VI) form is toxic and
should not be found in supplements (see below). |
|
Diuretics |
May cause temporary weight loss (due to water
loss), but not effective for sustained weight loss. |
Dandelion and asparagus are believed to be
mild diuretics, but well-controlled studies have not been done. |
Most are considered non-toxic, but some may
interact with medication or cause loss of electrolytes. |
|
Ephedra |
May aid weight loss by increasing metabolism. |
Shown effective when combined with caffeine. |
May cause high blood pressure, stroke and
serious heart problems — particularly if used with caffeine. In 2004 it
became illegal to sell ephedra as a supplement in the U.S. |
|
Forskolin |
May decrease body fat, enhance metabolism or
decrease hunger. |
One small, 3-month clinical study in
overweight and obese men found 250 mg of a 10% forskolin extract (Forslean, Sabinsa)
taken twice daily significantly decreased body fat, increased in lean muscle,
bone mass and free testosterone levels, but did not result in weight loss (Godard, Obes Res, 2005).
In women who were slightly overweight, the same dose had no effect on body
weight or composition, but did decrease hunger (Henderson, J Int Soc Sports Nutr
2005). (May also have some benefit in asthma and other conditions
(Gonzalez-Sanchez, J Int Med Res 2006)) |
May lower blood pressure or increase heart
rate. Should be used only under physician supervision in people with low
blood pressure, people taking medication for blood pressure, and people
taking blood thinners, calcium channel blockers or nitroglycerine. |
|
Glucomannan |
A water-soluble fiber which expands in the gut
creating fullness and reduced appetite. May also improve cholesterol levels. |
Most, but not all, clinical studies suggest a
weight loss benefit, at least short term, using about 1 gram with each meal.
(Kiethly, Alt Ther 2005) |
Take with plenty of water to avoid it getting
stuck in throat as it expands. |
|
Green Coffee Bean Extract |
May cause modest weight loss. |
Several small, short-term studies show modest
weight loss (about 2 lbs per month more than with
placebo). Levels of chlorogenic acids (CGAs) in products may be important.
[Note: Several products have failed ConsumerLab.com testing]. |
No adverse reactions reported, but studies
have not been long-term. May affect blood pressure and blood sugar levels. |
|
Green Tea |
May aid weight loss and protect against weight
gain. |
Studies suggest that green tea extract
providing 270 to 432 mg EGCG/day might help reduce weight in moderately obese
patients. |
Generally safe. Stimulant side- effects due to
caffeine content. |
|
Hoodia |
Believed to suppress appetite, but not proven
in clinical trial. |
Study in overweight women showed no benefit. |
Study in overweight woman showed increased
nausea, vomiting and skin sensations, and increases in blood pressure and
heart rate. |
|
Hydroxycitric Acid |
May aid weight loss by interfering with fat
metabolism or appetite suppression. |
There is mixed evidence that Garcinia may
reduce food intake; it doesn't, however, seem to help obese people lose
weight. The dose used generally contains 500 mg of HCA taken three to four
times a day. |
Generally safe but no long term studies. Some
side effects that have been reported include nausea, GI discomfort, and
headache. |
|
L-Carnitine |
Purported to improve fat metabolism by
shuttling fatty acid into the cell's mitochondria. |
Little evidence of effect on obesity,
(although appears useful in some cardiac diseases). |
Generally safe. |
|
Pyruvate and 1-dihydroxyacetone- DHA. |
May have modest effect on weight loss —
particularly fat loss. Pyruvate may also have a cholesterol-lowering and
blood pressure-lowering effect. |
Small studies are suggestive of efficacy. More
research needed. Original research used 20 to 30 grams per day. More recent
studies indicate an effect with 3 to 5 grams per day. |
No serious side effects when taken orally.
Large doses (over 5 grams per day) may cause abdominal discomfort, bloating,
gas and diarrhea. |
|
Promoted to cause weight loss in people by
promoting fat breakdown. |
No weight loss studies in humans. In mice fed
high-fat diet, prevented weight gain and promoted fat breakdown (Morimoto, Life Sci 2005). Fat breakdown also
shown in cell experiment (Park, Planta Med 2010). |
Safe as a food additive, but no safety studies
at amounts in supplements --100 mg or more per day. (In comparison, 1 pound of
raspberries provides about 1 mg of ketone.) Due to lack of information about
possible metabolic and other effects, people with pre-existing health
conditions (diabetes, high cholesterol, high blood pressure, etc.) should be
monitored by a health care professional when using raspberry ketone. Be aware
that raspberry ketone is different from the supplement raspberry leaf. |
|
|
Stimulant Laxatives |
May cause temporary weight loss, but not
effective for sustained weight loss. |
By the time that laxatives act on the large
intestine, most foods and calories have already been absorbed by the small
intestine, through which food first passes. |
Laxatives will cause the loss of water,
minerals, and electrolytes. Chronic use may lead to dehydration, electrolyte
imbalance, kidney failure and even death. See information about the dangers of laxative abuse from
the National Eating Disorders Association. The State of California requires a
warning label on these products. |
|
Vitamin C |
May help with weight loss in significantly
overweight individuals. |
Small studies are suggestive of efficacy. More
research needed. |
Safe, though in high doses (1,000 mg), may
cause diarrhea. |
|
White Kidney Bean Extract "Starch
Blocker" |
Promoted as a starch "blocker" or
"neutralizer" for weight loss and body fat loss. |
May not be effective for weight loss, but may
modestly help reduce body fat at doses ranging from 445 mg to 3,000 mg per
day. (Onakpoya, Br J Nutr 2011).
Look for extracts standardized to provide a certain amount of alpha amylase
inhibiting units (AAIU) per gram, such as 3,000 AAIU. |
Generally safe in short term clinical studies,
with the most commonly reported side effect being mild gastrointestinal
symptoms. Studies of long-term safety needed. |
ConsumerLab.com focused its testing in this Review on products containing
7-keto DHEA, blends with stimulant herbs or caffeine, and forskolin.
Quality Concerns and Tests
Performed:
Neither the FDA nor any
other federal or state agency routinely tests supplements for quality prior to
sale. Yet, there are many potential problems: Amount of key ingredient:
It is important to know that a product contains the ingredient(s) that it
claims. Too little and you may not get the expected benefit — as well as waste
your money. Too much, and you may experience negative effects. ConsumerLab.com
identified one or more key ingredients (7-keto DHEA, caffeine, synephrine
and/or forskolin) in each product to confirm its identity and measure the
amount in a daily serving.
Heavy metal contamination:
Supplements containing whole herbal ingredients can be contaminated with lead
or other heavy metals such as cadmium and arsenic if grown in a contaminated
environment. These metals can cause toxicity. Supplements containing large
amounts of minerals may also be contaminated with heavy metals. Products with
significant amounts of whole herbs or minerals were tested for lead, cadmium,
and arsenic.
Ability to break apart:
All tablet and caplet products were also tested for their ability to
disintegrate properly and release their contents in the body.
Caffeine:
Caffeine is commonly found in weight loss supplements — added directly or found
within herbal ingredients such as green tea, guarana and kola nut. The total
amount of caffeine in supplements is not always disclosed. Because of
caffeine's potential side effects, and potential for increasing the side
effects of other stimulants, such as the synephrine in bitter orange, it is
useful to know the amount of caffeine in a daily dose.
For more information about the testing, see How Products were Evaluated.
What CL Found and Top Picks:
7-keto DHEA
ConsumerLab.com selected three 7-keto-DHEA products for testing, and all three
passed. Each of these provided 100 mg of 7-keto DHEA per pill as labeled. An
additional product, Puritan's Pride 7-Keto DHEA, which lists 25 mg
of 7-keto DHEA per softgel, also passed testing and
was Approved through ConsumerLab.com's
voluntary Quality Certification Program.
As shown in the graph below, there was a wide range across the products in the
cost to obtain 100 mg of 7-keto DHEA, the dose that has been used in clinical
trials when given twice daily, as discussed above. The cost ranged from 33
cents for Life Extension 7-Keto DHEA Metabolite 100 mg to $1.40
from Puritan's Pride.
Top Pick for 7-Keto DHEA
Our Top Pick for 7-keto DHEA is Life Extension 7-Keto
DHEA Metabolite 100 mg. In addition to containing its listed amount of
7-keto DHEA and suggesting a dose consistent with clinical trials, it is by far
the least expensive product for obtaining 7-keto DHEA. Life Extension includes
other ingredients that have shown some weight loss benefit (such as vitamin C
and green tea) but at doses below those typically used for that purpose. It
also includes a relatively small amount of bioavailability-enhanced curcumin.
Stimulant Blends
Popular in the market, stimulant herbal blends may help cause weight loss in
the short-term. These products typically contain significant amounts of
caffeine from ingredients such as green tea or guarana or added as anhydrous
caffeine (which is caffeine minus the little bit of water that can be
associated with it, making it drier and easier use in supplement
manufacturing). Products may also contain another stimulant, such as synephrine
from bitter orange.
ConsumerLab selected six stimulant blend supplements
(including one with forskolin). Four of these listed amounts of caffeine on
their labels while the other two only showed caffeine or caffeine-containing
herbs as part of a proprietary blend. One of these also indicated that it
contained synephrine -- as a percentage of a listed amount of bitter orange extract.
Among these, the only product to fail testing (listed as "NOT APPROVED" in the Results
table below) was Premier Research Labs Lean Advantage — the
product with synephrine from bitter orange. We found it to contain twice the
listed amount of synephrine: 120.9 mg per 3 capsules serving rather than the
listed 60 mg. Each dose was also found to contain 63.6 mg of caffeine, likely
from green coffee bean extract and green tea listed as ingredients. The U.S.
FDA has not established limits on use of synephrine, but Canada has approved
the use of up to only 50 mg per day of synephrine in healthy adults (or 40 mg
per day when combined with 320 mg or less of caffeine).
As shown in graph below, supplements that specifically listed their amounts of
caffeine were found to contain these amounts, which were the highest among the
tested products. In fact, three of these contain amounts of caffeine that exceed a European safe limit on caffeine per
dose (200 mg) and/or per day (400 mg) based on the serving suggestions on their
bottles. Consequently, these three could not be Approved and are listed as
"NR" (not rated) along with a caution. For example, both Burn
XT and Muscletech Hydroxycut Hardcore Elite each provided 270 mg of
caffeine per 2-capsule serving and 540 mg with an optional additional serving.
They did, however, include instructions that could help reduce the chance of
negative effects: Burnt XT directs users to assess their
tolerance by starting with a single capsule rather than the regular serving of
two. It also suggests that a second serving (another 2 capsules) "may be
added 5-6 hours later," rather than taking both doses together. Muscletech Hydroxycut suggests
starting with a single capsule for two days, increasing to four capsules daily
by the end a week.
As a reference, 200 mg of caffeine is the amount in about two cups of coffee or
5 cups of green tea or cola. While this may not seem like an awfully large
amount, the problem is that it is taken all at once rather than over an
extended period of time. Large amounts of caffeine taken this way can cause
side-effects including insomnia, nervousness, tremors, gastric irritation,
nausea, headache and increased urination. Doses larger than 250-300 mg per day
have been associated with irregular heart rhythm.
Top Pick for
Stimulant Blends
If you are going to try a stimulant blend supplement for weight loss, it would first
seem best to avoid those with potentially dangerous levels of caffeine or
synephrine, i.e., those marked with "Caution" in the Results table below and discussed above.
Only two stimulant blend products were "APPROVED" in our
review, Herbalife Total Control (82 mg of caffeine per tablet
costing 54 cents, to be taken 3 times per day) and Rock Star Skinny Gal
Thermogenic (51.6 mg of caffeine found per capsule costing 50 cents,
to be taken twice a day). Each of these include additional ingredients (not
tested), but it is far from clear that any of these will aid weight loss. For
example, Herbalife Total Control includes a proprietary blend
composed of undisclosed amounts of various tea leaf extracts and pomegranate
rind extract while Rock Star Skinny Gal includes relatively
insignificant amounts of Garcinia, conjugated linoleic acid (CLA), and white
kidney bean in addition to undisclosed amounts of more than ten ingredients
such as green coffee bean and apple cider vinegar in a proprietary blend.
To our knowledge, neither of these formulas have been clinically tested and
shown to aid weight loss. However, if you are eager to try one of these products,
our Top Pick would be Herbalife Total Control as
it provides a bit more caffeine, although still at a safe level. It would seem
best to take the pills with meals to reduce the risk of liver toxicity that
has been reported, although infrequently, when high-dose green tea extracts
have been taken without food.
Forskolin
As noted earlier, limited evidence suggests that forskolin (from Coleus
forskohlii) may aid in fat loss or reduce hunger
when 250 mg of a 10% forskolin extract (Forslean from
Sabinsa) (providing 25 mg of forskolin) is taken
twice daily.
ConsumerLab selected five forskolin supplements for
review, one of which included a stimulant blend. One product, BioGanix Pure Forskolin Extract was NOT APPROVED because it contained
just 1.9 mg of forskolin per capsule rather than its listed 50 mg. Muscletech® Hydroxycut
Hardcore Elite, which, as noted earlier, could not be approved due to its
high level of caffeine, listed 100 mg of Coleus forskohlii extract
and was found to provide 12.3 mg of forskolin -- the lowest amount in the
group.
Top Pick for
Forskolin
Three products were APPROVED in testing: Nature's
Answers Forskohlii Weight Control (50 mg of
forskolin per capsule), Nature's Plus Herbal Actives Coleus Forskohlii (25 mg forskolin per capsule),
and Paradise Coleus Forskolii (25 mg
forskolin per capsule). Nature's Answer was the least
expensive product for obtaining forskolin, as shown in the graph below.
However, our Top Pick was the second least-expensive
source of forskolin, Paradise Coleus Forskolii,
as it provided the 25 mg serving size that has been used clinically. Although
the bottle suggests that it be taken once per day, twice per day use would
better replicate its use in clinical trials.
Test Results by Product:
Listed below are the test
results for fourteen supplements used for weight or fat loss. Thirteen were
selected by ConsumerLab and one product (indicated
with a CL flask icon) is included for having passed the same evaluation through
ConsumerLab.com's voluntary Quality Certification Program.
Products are shown alphabetically within each ingredient category. Also shown
are labeled suggested serving sizes and claimed amounts of 7-keto DHEA,
caffeine, synephrine, and forskolin in products or found in them when claimed
amounts were not listed or were incorrect. Products listed as
"Approved" met their label claims for these key ingredients and other
quality requirements (see Passing Score). Products
listed as "NR" could not be rated since they provided more caffeine
or synephrine than known to be safe for adults. The full list of labeled
ingredients is available for each product is found in the last column.
Results of ConsumerLab.com
Testing of 7-KETO DHEA, STIMULANT, AND FORSKOLII WEIGHT MANAGEMENT SUPPLEMENTS
(Click arrows or swipe left or right to see all columns)
Approval Status
Product Name
(Suggested Serving on Label)
Contained Claimed Amount(s)ⓘ of
Key Ingredient(s) Per Suggested Serving
Suggested Daily Serving on Label
Pill Sizeⓘ
Cost for Suggested Serving
Price
Notable Features and Other Weight Loss/Slimming
Ingredients Listing Amounts
Full List of Ingredients
(Per Serving)
7-Keto DHEA Supplements:
APPROVED
Douglas Laboratories 7-Keto™
Mfd. by Douglas Laboratories
1 vegetarian capsule:
100 mg 7-Keto DHEA
✔
As a dietary supplement, adults take 1 capsule
twice daily or as directed by your healthcare professional.
Medium/large vegetarian capsule
$1.13
$67.60/60 vegetarian capsules
This product contains NO yeast, gluten, soy,
milk/dairy, corn, sodium, sugar, starch, artificial preservatives, artificial
flavoring, or genetically modified organisms (GMOs).
1 vegetarian capsule:
7-Keto™ (3-Acetyl-7-oxo-dehydro-epiandrosterone) 100 mg.
Other Ingredients: Cellulose and vegetable stearate.
APPROVED
Top Pick
Life Extension® 7-Keto® DHEA Metabolite 100 mg
Dist. by Quality Supplements and Vitamins, Inc.
1 vegetarian capsule:
100 mg 7-Keto DHEA
✔
Take one (1) capsule upon waking and one (1)
capsule before midday meal, preferably on an empty stomach, or as recommended
by a healthcare practitioner.
Large vegetarian capsule
$0.33
$20.00/60 vegetarian capsules
None.
1 vegetarian capsule:
Vitamin C (as ascorbyl palmitate) 11 mg, 7-Keto® DHEA
(7-oxo-dehydro-epiandrosterone-3b-actetate) 100 mg, BCM-95® Bio-Curcumin®
turmeric 25:1 extract (root) [std. to 95% Total Curcuminoids Complex with
Essential Oils of Turmeric Rhizome by HPLC] 25 mg, more...
APPROVED
Puritan's Pride® 7-Keto® DHEA 25 mg
Mfd. by Puritan's Pride, Inc.
1 softgel:
25 mg 7-Keto DHEA
✔
For adults, take one (1) softgel
up to four times daily, preferably with a meal.
Medium/large softgel
$0.35
$20.99/60 softgels
No Artificial Flavor or Sweetener, No Preservatives,
No Sugar, No Starch, No Milk, No Lactose, No Gluten, No Wheat, No Yeast, No
Fish, Sodium Free.
Precaution: Contains soy ingredients.
1 softgel:
7-Keto® - Dehydro-epiandrosterone Acetate 25 mg.
Other Ingredients: Soybean Oil, Gelatin, Vegetable Glycerin, Soy Lecithin,
Yellow Beeswax, Titanium Dioxide Color.
APPROVED
Source Naturals® 7-Keto®
Dist. by Source Naturals, Inc.
1 tablet:
100 mg 7-Keto DHEA
✔
1 tablet twice daily.
Medium circular tabletⓘ
$0.61
$36.75/60 tablets
Suitable for vegetarians and Hypoallergenic:
contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar,
starch, salt, preservatives, or artificial color, flavor or fragrance.
1 tablet:
7-oxo-DHEA Acetate 100 mg.
Other Ingredients: Microcrystalline cellulose, stearic acid, and magnesium
stearate.
Stimulant Blend Supplements:
NRⓘ
Burn XT™
Dist. by Jacked Factory
2 veggie capsules:
270 mg caffeine
✔
Caution:
High level of caffeine and very high level of caffeine if 2nd serving added
First Time Directions: Consume One Capsule To
Assess Tolerance Before Increasing Your Dosage. Regular Use: As A Dietary
Supplement, Consume One Serving (2 Capsules) With A Glass Of Water In The
Morning Upon Waking, An Additional Serving, more...
$1.00
$29.99/60 veggie capsules
Green Tea Leaf Extract (98% Polyphenols, 75%
Catechins, 45% EGCG) 450 mg
2 veggie capsules:
Acetyl-L-Carnitine HCl 700 mg, Green Tea Leaf Extract (98% Polyphenols, 75%
Catechins, 45% EGCG) 450 mg, Caffeine Anhydrous 270 mg, Capsimax®
Cayenne Pepper Fruit Extract 50 mg, Bioperine® Black
Pepper Fruit Extract 5 mg.
Other Ingredients: Hypromellose Capsule And Leucine.
APPROVED
Top Pick
Herbalife® Total Control®
Dist. by Herbalife International of America,
Inc.
1 tablet:
82 mg caffeine
✔
Take 1 tablet 3 times per day.
Medium/large tabletⓘ
$0.54
$48.99/90 tablets
Precaution: Contains Soy And Wheat.
1 tablet:
Total Carbohydrates <1 g, Proprietary Blend [Ginger Root Extract, Green Tea
Leaf Extract, Oolong Tea Leaf Extract, Black Tea Leaf Extract and Pomegranate
Rind Powder Extract] 353 mg, Caffeine (from natural caffeine powder and teas)
82 mg.
Other Ingredients: Microcrystalline Cellulose, more...
NOT APPROVED
Premier Research Labs Lean Advantage™
Mfd. by Premier Labs, LP
3 vegetarian capsules:
60 mg synephrine
Found 120.9
mg synephrine per 3 vegetarian capsules (201.6% of listed amount)
Caution:
Very high level of synephrine
(Found 63.6 mg caffeine per 3 vegetarian capsule)
Due to significant amount of turmeric, also tested for heavy metals. Met
passing requirements.ⓘ
Take 3 capsules at breakfast or before 2:00PM or
as directed by a health professional.
Large vegetarian capsule
$0.83
$24.95/90 vegetarian capsules
Pure Vegan. No Added Undesirable Excipients. No
Chemical or Radiation Sterilization, Screened for Clandestine Adulteration.
Green Coffee Bean Extract (Coffea robusta)
(standardized to 200 mg Chlorogenic Acid) 468 mg
AdvantraZ® Bitter Orange, more...
3 vegetarian capsules:
Green Coffee Bean Extract (Coffea robusta)
(standardized to 200 mg Chlorogenic Acid) 468 mg, AdvantraZ®
Bitter Orange (fruit) Extract (Citrus aurantium) (Standardized to 60 mg
Synephrine) 144 mg, Lean Advantage Pro Blend [Organic Rice Fiber, Organic
Chlorella (whole broken cell wall), more...
APPROVED
Rock Star™ Skinny Gal™ Thermogenic
Dist. by Rockstar LLC
1 capsule:
no claimed amount of caffeine
(Found 51.6 mg caffeine per capsule)
Take 1 capsule every day and before a meal.
Large capsule
$0.50
$29.95/60 capsules
Garcinia (Garcinia cambogia) (Fruit) 40 mg
Conjugated Linoleic Acid (from Safflower Oil) 15 mg
White Kidney (Phaseolus vulgaris) (Bean) 10 mg
1 capsule:
Garcinia (Garcinia cambogia) (Fruit) 40 mg, African Mango (Irvingia
gabonensis) (Seed) 25 mg, Conjugated Linoleic Acid
(from Safflower Oil) 15 mg, White Kidney (Phaseolus vulgaris) (Bean) 10 mg,
Proprietary Blend [Caffeine Anhydrous, more...
NRⓘ
Xenadrine™ Ultimate Weight Loss
Dist. by Iovate Health
Sciences U.S.A. Inc.
2 capsules:
200 mg caffeine
✔
Caution:
High level of caffeine and very high level of caffeine if 2nd serving taken
Day 1 to 3: Take 1 capsule, twice a day; Day 4 and
beyond: Take 2 capsules, twice a day.
Large capsule
$0.26
$15.38/120 capsules
None.
2 capsules:
Weight Loss and Metabolic Intensity Complex [Robusta coffee bean extract
(as Coffea robusta) [Standardized to 45%
chlorogenic acids] 200 mg, Caffeine anhydrous (1,3,7-trimethyl-xanthine) 200
mg, Yohimbe bark extract (as Pausinystalia
yohimbe) [Standardized to 6% yohimbine]] 420 mg, more...
Forskolin Supplements:
NOT APPROVED
BioGanix® Pure Forskolin Extract
Dist. by BioGen®
1 capsule:
250 mg Coleus forskohlii root
extract
50 mg forskolin
Found only
1.9 mg forskolin per capsule (3.7% of listed amount)
As a dietary supplement take one (1) capsule in
the morning preferably 30-45 minutes before a meal, with an 8 oz glass of
water. For the maximum weight loss dosage, you can take one (1) capsule twice a
day or advised by your healthcare professional.
Large capsule
$0.22
$19.97/90 capsules
Stimulant Free. Non-GMO.
1 capsule:
Forskolin (Coleus Forskohlii Root Extract)
(Standardized 20% [50 mg] forskolin) 250 mg.
Inactive Ingredients: Cellulose (Vegetable Capsule), Rice Flour.
APPROVED
Nature's Answer® Forskohlii
Weight Control
Mfd. by Nature's Answer®
1 vegetarian capsule:
250 mg Forskohlii root extract
50 mg forskolin
✔
As a dietary supplement, take one (1) capsule
twice a day.
Large vegetarian capsule
$0.30
$18.19/60 vegetarian capsules
Vegan.
1 vegetarian capsule:
Forskohlii (Coleus forskohlii)
Root Extract (standardized to 20% Forskolin, 50 mg) 250 mg.
Other Ingredients: Microcrystalline Cellulose, Vegetable Cellulose (capsule),
Calcium Silicate.
APPROVED
Natures Plus® Herbal Actives Coleus Forskohlii
Mfd. by Natural Organics Laboratories, Inc.
1 vegetarian capsule:
125 mg ForsLean® (Coleus forskohlii root
extract)
25 mg forskolin
✔
As a dietary supplement offering the consistent
benefits of exact potency, one capsule daily or as recommended by your health
care professional.
Large vegetarian capsule
$0.48
$28.95/60 vegetarian capsules
Gluten Free. Hypo-Allergenic. Vegetarian.
1 vegetarian capsule:
ForsLean® (Coleus forskohlii root
extract) (standardized 20% [25 mg] forskolin) 125 mg, Activessence®
(a patented enzyme activation system - Cellulase, Pectinase, Hemicellulase and Xylanase) (forskolin-liberating enzymes) 25
mg, more...
APPROVED
Top Pick
Paradise® Coleus Forskolii
Dist. by Paradise Herbs & Essentials, Inc.
1 vegetarian capsule:
250 mg Coleus forskohlii root
extract
25 mg forskolin
✔
1 vegetarian capsule or as directed by a
qualified health care professional.
Medium/large vegetarian capsule
$0.33
$19.99/90 vegetarian capsules
Vegan. Non-GMO. Gluten Free. Contains No common
allergens. Made without fillers.
1 vegetarian capsule:
Coleus Forskohlii root extract (10% forskolin) 250
mg.
Other Ingredients: Vegetarian Capsule (plant cellulose).
Combination Forskolin and Stimulant Blend
Supplements:
NRⓘ
Muscletech® Hydroxycut
Hardcore Elite
Dist. by Iovate Health
Sciences U.S.A. Inc.
2 thermo caps:
270 mg caffeine
✔
Caution:
High level of caffeine with 2 capsules and very high level when exceeding 2
capsules daily
100 mg Coleus extract (as Coleus forskohlii)
(root)
(Found 12.3 mg forskolin per 2 thermo caps)
Day 1 & Day 2: 1 capsule, 1x daily; Day 3
& Day 4: 2 capsules, 1x daily; Day 5 & Day 6: 2 capsules with meal 1, 1
capsule with meal 2; Day 7 & Beyond: 2 capsules, 2x daily.
Large thermo caps
$0.32
$15.80/100 thermo caps
None.
2 thermo caps:
Caffeine anhydrous 270 mg, C. canephora robusta extract (bean) (robusta
coffee) [Standardized for 45% chlorogenic acids] 200 mg, Coleus extract
(as Coleus forskohlii) (root)
[Standardized for forskolin] 100 mg, L-theanine 100 mg, Cocoa extract, more...
Unless otherwise noted, information about the
products listed above is based on the samples purchased by ConsumerLab.com (CL)
for this Product Review. Manufacturers may change ingredients and label
information at any time, so be sure to check labels carefully when evaluating
the products you use or buy. If a product's ingredients differ from what is
listed above, it may not necessarily be of the same quality as what was tested.
The information contained in this report is
based on the compilation and review of information from product labeling and
analytic testing. CL applies what it believes to be the most appropriate
testing methods and standards. The information in this report does not reflect
the opinion or recommendation of CL, its officers or employees. CL cannot
assure the accuracy of information.
Copyright ConsumerLab.com, LLC, 2021 All
rights reserved. Not to be reproduced, excerpted, or cited in any fashion
without the express written permission of ConsumerLab.com LLC
ConsumerTips™:
For Chromium see Chromium Review
For CLA see CLA Review
What to Consider When Buying:
·
7-Keto-DHEA
7-keto-DHEA should not be confused with DHEA (see
separate Review of DHEA). Their
effects are quite different. Although chemically related, DHEA gets converted
in the body to androgen and estrogen hormones, while 7-keto-DHEA does not.
·
Stimulant Herbal Blends:
Often products contain "proprietary" blends or formulas that do not
show the amount of each specific ingredient. Since such products have typically
not undergone rigorous human testing, it is not known whether these formulas
are effective, or even safe. It is preferable to use products that show the
amount of every ingredient.
·
Forskolin:
Clinical studies have used a dose of 250 mg of Coleus forskohlii extract standardized to 10% (25 mg) of
forskolin given twice daily, based on a branded extract, Forslean® from Sabinsa.
Some products contain a 20% extract that can provide the same amount of
forskolin from 125 mg of extract
What to Consider When
Using:
·
7-Keto-DHEA
A dose of 100 mg twice daily has been shown to be effective for weight loss in
clinical studies in which overweight or obese subjects engaged in exercise with
a reduced-calorie diet, Subjects taking 7-keto DHEA lost more weight than those
taking placebo (Kaiman, Cur Ther
Res 2000). Similar results were found in a study using 7-keto DHEA
in combination with other ingredients (L-tyroxine, asparagus
root extract, choline bitartrate, inositol, copper gluconate, manganese, and
potassium iodide (trademarked 7-Keto Naturalean) (Zenk,
Cur ther Res
2002) . 7-keto DHEA appears to increase the resting metabolic
rate in obese people on a calorie-restricted diet (Zenk J Nutr Biochem 2007).
·
Stimulant Herbal Blends:
Keep in mind that all of the following may contain significant amounts of
caffeine: green, white, and black tea; guarana; kola (cola) nut; cacao (cocoa);
coffee; and Yerba maté (Paraguay tea, ilex). Some
labels will indicate the amount of caffeine contained within each herbal
ingredient, such as "standardized to caffeine (40%)." Some products
may also have added caffeine, often listed as "anhydrous caffeine."
If you decide to use one of these products, you may want to start with a low
dose and evaluate side effects before progressing to the standard daily dose.
·
Forskolin:
There are just two small published clinical studies on the use of forskolin for
weight loss. In one, overweight and obese men who took 250 mg of a 10%
forskolin extract (Forslean®, Sabinsa Corp.) twice daily for 3 months did not lose
weight, but did have a significant loss of body fat and increase in lean muscle
compared to men who took a placebo (Godard, Obes Res, 2005).
In addition, the men who took forskolin had significant increases in bone mass
and free testosterone levels, compared to the men who took a placebo. A second
clinical trial that investigated the effects of the same dose of Forslean® in women who were slightly
overweight found no changes in body weight or composition compared to placebo,
although women taking the extract reported significantly less hunger (Henderson, J Int Soc Sports Nutr
2005). The study did not measure the effects on testosterone levels
in women.
Concerns and Cautions:
·
7-Keto-DHEA:
Has been used safely at a dose of up to 200 mg per day with no serious
side-effects, but studies in humans have been limited in size and duration (1
to 8 weeks). In one study a subject experienced decreased hemoglobin and
hematocrit, but the significance of this is unclear. Treatment may decrease
diastolic blood pressure and thyroxine levels. 7-keto DHEA does not
significantly affect sex hormone levels that occur with DHEA supplementation. (Davidson, Clin Invest Med 2000). Treatment may
increase triiodothyronine (T3) levels (Kaiman, Cur Ther
Res 2000).
·
Stimulant Herbal Blends:
Chronic use, especially in large amounts, of caffeine from any source can produce
tolerance, habituation, psychological dependence, and other effects. Doses
greater than 250-300 mg per day have been associated with significant adverse
effects such as tachyarrhythmias and sleep disturbances.
An expert panel of the European Food Safety Authority
(2015) determined that caffeine up to 200 mg per single
dose (about 3 mg/kg of body weight for a 70-kg adult) does not give
rise to safety concerns. In addition, habitual caffeine consumption (i.e.,
ongoing daily consumption) of up to 400 mg total per day does
not give rise to safety concerns for adults, except the daily limit is 200 mg
for women or are pregnant or breast feeding. For children and adolescents the
information available is insufficient to derive a safe caffeine intake. ConsumerLab applied these limits in determining its
approval status of products in this Review.
A study of four popular stimulant dietary supplements found all to cause
significant increases in blood pressure and changes in heart rate or rhythm.
The study was conducted on healthy young men given 2 pills of each supplement 3
times daily for 3 days. The most common reported side effects were nausea,
insomnia, and increased anxiety (Foster, Clin Pharm & Ther
2013). Bacterial contamination was also found in Xenadrine
EFX and Guarana. The results of this small study are shown below, including the
amount of caffeine found in each product. The researchers cautioned that use of
stimulant supplements like these should be discouraged in individuals with
hypertension, diabetes, or other cardiovascular diseases.
Effects of Stimulant Dietary Supplements
|
Zantrex 3 |
Xenadrine EFX |
Guarana (Solaray) |
Metabolift |
|
|
Caffeine Per Pill |
183 mg |
123 mg** |
116 mg |
90 mg |
|
Blood Pressure Increase* (mm Hg) |
+11.8 |
+11.4 |
+10.5 |
+8.4 |
|
Increased Heart Rate |
Yes |
Yes |
Yes |
|
|
Abnormal Heart Rhythms |
Yes |
Yes |
||
|
Side Effects (# of people affected out of 12)
*** |
Nausea (6), insomnia (5), skin flushing (2),
headache (2), frequent urination (2), loss of appetite (2) |
Nausea (6), insomnia (2), anxiety (3),
indigestion (2) |
Nausea (3), insomnia (3), anxiety (2), tremors
(2) |
Insomnia (4), anxiety (3) |
·
*Mean increase in systolic blood pressure on day 1 of study
compared to pre-supplement level.
**Also contained theobromine (4.6 mg) and theophylline (1.7 mg), which are
other natural stimulants.
*** Side effects experienced by 20% or more people in study. Less common side
effects were abdominal cramping, vertigo, heart palpitations, tinnitus, loss of
appetite, and vomiting.
·
Forskolin:
Although no significant changes in blood pressure were found in clinical
studies using forskolin (Godard, Obes
Res, 2005; Henderson, J Int Soc Sports Nutr 2005), other evidence suggests forskolin
has the potential to lower blood pressure or increase heart rate. People with
low blood pressure and people taking blood pressure medications or blood
thinning drugs (Coumadin, Plavix) should only use forskolin under
physician supervision. It should not be taken by people who take calcium
channel blockers (Procardia, Cardizem) or nitroglycerine.
·
Acacia rigidula:
Supplements listed as containing the plant extract Acacia rigidula have been found to contain an
amphetamine-like compound called beta- methylphenylethylamine
(BMPEA) (Cohen, Drug Test Analysis 2015).
Animal studies suggest BMPEA could raise blood pressure and have effects
similar to other amphetamine-like substances, although its safety in humans has
not been studied.
Weight loss products found to contain BMPEA in the study were:
·
Aro Black Series Burn (Vitacost)
·
Black Widow (Hi-Tech Pharmaceuticals)
·
Dexaprine XR (iForce Nutrition)
·
Fastin-XR (Hi-Tech Pharmaceuticals)
·
Lipodrene Hardcore (Hi-Tech Pharmaceuticals)
·
Lipodrene Xtreme (Hi-Tech Pharmaceuticals)
·
MX-LS7 (iSatori)
·
Stimerex-ES (Hi-Tech Pharmaceuticals)
·
Yellow Scorpion (Hi-Tech Pharmaceuticals)
(See the April 8, 2015 Warning for
more details, and see the Muscle Enhancers Review for
sports supplements that were also found in the study to contain BMPEA.)
·
Deterenol and
other stimulants:
Another stimulant found in workout and weight loss supplements is deterenol, which may be listed on labels under other names,
including isopropylnorsynephrine, isopropylnorsynephrine
HCl, N-isopropylnorsynephrine HCl and isopropyloctopamine. Deterenol is
not approved in the U.S. for use in humans, either as a prescription drug or
supplement ingredient. Limited studies in people have shown that in doses
ranging from 2 to 3mg/kg, deterenol may cause adverse
effects such as flushing, tingling of extremities and face, anxiety, decreased
diastolic blood pressure and increased heart rate. At a dose of 5mg/kg, it can
cause inability to sit up, blurred vision, palpitations, weakness and
respiratory distress.
An analysis of 17 brands of supplements labeled as containing deterenol that are promoted for weight loss/fat burning and
other uses confirmed the following brands contained deterenol
(and in some cases, other stimulants as well), in doses of up to 17 mg per
serving, and up to 69 mg per day if taken as suggested on the label (Cohen, Clin Toxicol 2021):
·
Fastin
(Hi-Tech)
·
Oxy Lean Elite (GenOne
Laboratories
·
Thermo Shock (SciLabs
Nutrition)
·
OxyXtreme (6
Rings)
·
LipoTherm (ALR
Industries)
·
Blue Ice (EPG)
·
Optilean Plus (Kewlify)
·
Shredded-AF (Steel)
No deterenol
was detected in two weight loss/fat burning supplements that claimed to contain
deterenol: Thermal Black (Musclesport)
was found to contain only the stimularnt higenamine, and, Deep 6 Pro (Avenger Performance Nutrition)
was found to contain octodrine and 1,3-DMBA.
(The same study found a number of workout supplements also contained deterenol and/or other stimulants. Also see the March 26, 2021 warning for more details).
To further assist
consumers, ConsumerLab.com licenses its flask-shaped CL Seal of Approved
Quality (see The CL Seal) to manufacturers for use on labels
of products that have passed its testing. ConsumerLab.com will periodically
re-evaluate these products to ensure their compliance with ConsumerLab.com's
standards.
Information on this site
is provided for informational purposes only. It is not an endorsement of any
product nor is it meant to substitute for the advice provided by physicians or
other healthcare professionals. The information contained herein should not be
used for diagnosing or treating a health problem or disease. Consumers should
inform their healthcare providers of the dietary supplements they take.
Latest Clinical Research Updates for Weight Loss Supplements (7-Keto
DHEA, Forskolin and Stimulant Blend Supplements)
6/16/2013
Have you ever wondered
what taking a stimulant supplement for weight management or energy might do to
your body? Researchers recently gave Zantrex-3, Xenedrine
EFX, Metabolift, or a brand of Guarana to young men
while monitoring their heart rates and other vital signs, and recording side
effects. The results raise concerns. Get the details, plus test results for 14
other supplements, in the updated Weight Supplements Review >>
2/12/2012
Recently touted in the
media as a powerful tool for fat reduction, there has been a swell of interest
in supplements containing raspberry ketone. Do these supplements really work?
Although we have not yet had the time to test these products, we checked the
evidence on raspberry ketone and updated our Weight Supplements Review with
what we found. If you use raspberry ketone, use it with some caution --and be aware
that the quality of supplements can suffer when companies rush to meet a new
demand.
Green Tea Extract and Weight Loss
9/25/2011
A new study using a high
dose of green tea extract showed it to help sedentary overweight men lose
weight, while those taking placebo gained weight. This is not the first study
to show this potential benefit of green tea extract. The effect may be due to
the compound EGCG. Get the facts, including how much EGCG was in the product,
in the Weight Loss Supplements Review. More >>
Related CL Answers (13)
Green Coffee Bean Extract Supplements Review (for
Weight Loss)
Choose the Best Green
Coffee Bean Extract. 50% of Green Coffee Bean Extract Supplements Don't Deliver
Expected Ingredients.
Medically reviewed and
edited by Tod Cooperman, M.D.
Last Updated: 10/20/2020 | Initially Posted:
11/02/2012
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(NAD+/NADH, Nicotinamide Riboside, and NMN)
·
PQQ (Pyrroloquinoline Quinone)
Supplements Review
Table of Contents
Update
Updates: 11/28/12 -- Pure Health
Naturally Pure Green Coffee Bean - Contains 45% Chlorogenic Acids! —
This newer version of the Pure Health product first reviewed (see report below)
was tested at the request of its distributor, Pure Health, through ConsumerLab.com's Voluntary Certification Program.
Unlike the original product, this product includes the statement "Contains
45% Chlorogenic Acids!" on the front label. The product was found to
contain the claimed amount of chlorogenic acids and is listed as
"Approved" below. It was also found to contain 82 mg of caffeine per
2 capsule serving — higher than the original version and
than other products reviewed. Consumers should take note of the
differences in both the labeling and content of these products.
11/13/12 -- Pure Health Naturally Pure Green Coffee Bean --
Pure Health, the distributor of this product (reviewed below) informed
ConsumerLab.com that the product is being replaced in the market by a newer
version with a label stating it "Contains 45% Chlorogenic Acids." It
is apparently made with a different source of green coffee bean extract. The
version tested by ConsumerLab.com (expiration date May 2014) does not specify
its chlorogenic acid content and was found to contain 28.9% chlorogenic acids.
To gain Approval in this Review, ConsumerLab.com required these acids to
account for a minimum of 45% of the listed amount of extract -- the level
generally found in products shown to work in clinical trials.
Although the original Pure Health product
failed to meet ConsumerLab.com's requirement, Pure Health
has noted to ConsumerLab.com that, due to its product's relatively large
suggested dose of extract (800 mg to 2,400 mg per day), it delivers a larger
total amount of chlorogenic acids than some Approved products. While this is
true, ConsumerLab.com generally advises consumers to look for products similar
to those used in successful clinical trials, as the overall phytochemical
profile may be important.
What It Is:
As the name implies,
green coffee bean extract (or "green coffee extract") is an extract
from raw, green coffee beans — the same beans which are used to make coffee if
roasted. The extract contains substantial amounts of polyphenolic antioxidants
known as chlorogenic acids (CGAs) — comprising as much as 50% of most extracts.
It is these compounds which are believed to be important to the activity of
green coffee extract in the body. The extract also naturally contains some
caffeine, the amount of which may vary considerably across products (from about
1% to 10%), apparently depending on the extent to which the extract is
decaffeinated.
What It Does:
The CGAs in green coffee
bean extract appear to have a variety of effects, including a slight lowering
blood of pressure (Watanabe, Clin Exp Hypertens 2006; Kozuma, Hypertens Res 2005). However, it is most
commonly promoted for weight loss (See ConsumerLab.com Product Review of Weight Loss Supplements for
information about other weight loss supplements). Two small, short-term studies
(summarized below) using using a branded green coffee
bean extract (Svetol®, Berkem/Naturex) have been
performed in overweight individuals. Svetol is
made from decaffeinated green coffee beans and contains 45% to 50% total CGAs
(about one-third of which is the specific compound 5-caffeoylquinic acid
(5-CGA), and less than 2% caffeine).
The studies showed a modest, but statistically significant, weight loss
(roughly 3 lbs per month), among people taking green
coffee bean extract. However, those receiving placebo also lost some weight
(about 1 lb per month), so the additional weight loss
from the extract appears to be about 2 lbs per month.
The studies include the following:
·
200 mg twice per day (400 mg per day) of extract (Svetol®) for 12 weeks showed a mean weight loss of 10.9 lbs (4.97 kg) vs. 5.4 lbs (2.45
kg) for placebo. Weight reduction was somewhat higher than in other studies as
a bland, low-calorie diet given to both groups (Dellalibera, Phytotherapie 2007).
·
200 mg daily of extract (Svetol®)
added to instant coffee for 12 weeks showed a mean weight loss of 11.9 lbs (5.4 kg) vs. 3.7 lbs (1.69
kg) for placebo. (Thom, J Int Med Res 2007).
Sugar (as glucose) was added to the coffee, but there was a 6.9% reduction in
glucose absorption among those getting extract compared to those getting
placebo.
A 2012 study using another
green coffee bean extract, (GCA®, Applied Food Sciences) containing
45.9% total chlorogenic acids and 2 to 4% caffeine (Vinson, Diab, Met Synd and Obes, 2012),
was subsequently retracted in 2014 by its authors who conceded that they could
not assure the validity of the data. The retraction occurred as part of
settlement of a lawsuit brought by the U.S. FTC against Applied Food Sciences,
the manufacturer of the tested product, GCA®. The authors, from the University
of Scranton, did not conduct the study but had accepted data from researchers
in India who had performed the study with funding from Applied Food Sciences.
The published study had reported statistically significant weight loss over 6
weeks using two different doses of GCA®. (See the Warnings about the lawsuits
against Applied Food Sciences and Pure Green Coffee for
more information.)
In addition, a very short-term study conducted by The Dr. Oz Show in 2012 involved giving
100 women 400 mg of a proprietary green coffee extract three times daily (30
minutes before each meal) or placebo. There were no special changes in diet or
exercise. Over the two-week period of the study, those taking the extract
reported a 2 lb weight loss versus a 1 lb loss among those taking placebo. It is interesting that
the participants lost in just two weeks about the same amount of weight lost
per month in published studies. A possible explanation is that more weight loss
occurs during the initial weeks of treatment.
How It Works:
Exactly how green coffee
extract may work is not known. However, there is some evidence that it inhibits
an enzyme (hepatic glucose-6-phosphatase), reducing glucose production and
glucose levels — a potentially anti-diabetic effect (Henry-Vitac, J Ag Food Chem,
2010). This may force the body to use fats as energy, instead of
glucose.
Quality Concerns and
Tests Performed:
It is important that
products contain the chlorogenic acids (CGAs) found in the types of green
coffee bean extracts shown to work in clinical studies. As a manufacturer could
potentially skimp on an ingredient or even add CGA compounds to a supplement
without using actual green coffee extract, ConsumerLab.com purchased several
supplements sold in the U.S. and analyzed their chemical constituents, checking
for specific and total CGAs, as well as caffeine levels. These amounts were
expected to meet claimed amounts and, in the case of total CGAs, a minimum
expected content of 45%. Products were also checked for potential contamination
with lead and cadmium, heavy metals which can contaminate botanical products.
(See How Products Were Evaluated for more
information about testing.)
What CL Found:
Among the eight
supplements selected for testing by ConsumerLab.com, four did not contain
expected amounts of CGAs — ranging from no detectable CGAs to
81.2%:
·
Futurebiotics Green Coffee Bean
Extract contained
81.2% of its claimed 200 mg of total CGAs per capsule (i.e., instead of total
CGAs being 50% of the extract as claimed, it was 40.6%).
·
MaritzMayer Laboratories Pure Super
Green Coffee Bean Extract Double Strength contained only 13.8% of the minimum
total CGAs expected by ConsumerLab.com (i.e., instead total CGAs being 45% of
the extract, it was only 6.2%).
·
Nutri-Fusion Systems Green Coffee Bean Extract contained no
detectable CGAs, including none of the listed 5-CQA (a type of CGA). It also
had no detectable caffeine.
·
Pure Health Naturally Pure Green Coffee Bean contained only
64.4% of the minimum total CGAs expected by ConsumerLab.com (i.e., instead of
total CGAs being 45% of the extract, it was only 28.9%). (See Updates above regarding a newer
version which has been Approved.)
Starbucks VIA Refreshers
COOL LIME with Green Coffee Extract was also among the products selected for
testing, although it is not a dietary supplement and does not list the actual
amount of green coffee extract. We were curious to know what it delivers. We
found that a half packet (the serving listed on the package) contained the
equivalent of 180 mg of extract — a sizable amount, and more than in some of
the "supplements" listed above.
Selecting a Quality-Approved Product
Three supplements passed testing as did another five tested through ConsumerLab.com's voluntary Quality Certification Program.
These products suggested total daily dosages of extract ranging from 100 mg to
2,400 mg. Clinical studies have used approximately 200 mg to about 1,200 mg per
day of extract, and it's not at all clear that taking more than in this range
is desirable. However, most dosages involve taking multiple capsules, so you
can adjust the daily dosage.
Be aware that the amount of caffeine in the products ranged from as little as 4
mg to 200 mg per suggested serving (see the 3rd and 6th columns in the table
below for these amounts). Consequently, some products may make you feel more
stimulated, or even jittery, than others. A cup of regular brewed coffee, for
comparison, contains about 95 mg of caffeine. The differences among products
are apparently due to levels to which their extracts are decaffeinated (except
in the case of GNC Total Lean Metabolic Elite, to which a
significant amount of caffeine has been added). As noted earlier, most studies
have used extracts with lower amounts of caffeine.
In terms of cost, the most economical product was Vitacost
Green Coffee Bean Extract 400 mg capsules at 20 cents per 400 mg.
Several other Approved products were close in cost per 400 mg of extract: Pure
Health Naturally Pure Green Coffee Bean - Contains 45% Chlorogenic Acids! (22
cents), Paradise Herbs, Green Coffee Bean (23 cents), Life
Extension Green Coffee Extract CoffeeGenic™ (24
cents — and is made with GCA®), and Labrada
Nutrition Green Coffee Bean Extract (27 cents) -- see the last column
of the table below for more price comparisons. The four Approved products
containing Svetol® (CVS/pharmacy,
Garden of Life, Reserveage, and Vitamin
World were considerably more expensive than most products, costing 80
to 98 cents per 400 mg of extract. The GNC product, which
contains a much smaller amount of green coffee bean extract than the other
products but has many additional ingredients, was the most costly in terms of
getting green coffee bean extract.
Test Results by Product:
Listed below are the test
results for seventeen green coffee bean extract products. Nine products were
selected for review by ConsumerLab.com and eight products passed the same
testing in the Quality Certification Program. If a product is listed as
Approved, it was found to contain the labeled and expected amounts of compounds
and did not exceed CL's stringent criteria for lead or cadmium contamination.
The full list of ingredients and nutrients is available for each product by
clicking on the word Ingredients in the first column. For more information
about testing go to How Products Were Evaluated.
|
CONSUMERLAB.COM
RESULTS FOR GREEN COFFEE BEAN EXTRACT (GCBE) PRODUCTS |
|||||||
|
Product Name, Extract
Per Unit, and Suggested Daily Serving on Label |
Listed Amounts Per
Daily Serving:
|
Listed Amount of
Caffeine Per Daily Serving |
--TEST RESULTS-- |
Cost of Suggested
Daily Serving on Label |
|||
|
OVERALL RESULTS: |
Contained Expected
Claimed and Minimum Amounts of Total CGAs** and, if Listed, 5-CQA |
Contained Claimed
Amount of Caffeine |
Did Not Exceed Conta-mination Limits for Lead and Cadmium |
||||
|
CVS/pharmacy™ Green Coffee Bean |
400 mg GCBE 180 mg total CGAs |
24 mg |
APPROVED |
|
|
|
$0.36 |
|
Futurebiotics Green Coffee Bean Extract |
400 mg GCBE |
No more than 16 mg |
NOT |
Found only 81.3% of
claimed amount of total CGAs |
|
|
$0.33 |
|
Garden of Life® fucoTHIN®
Green |
800 mg GCBE 400 mg total CGAs2 |
NL |
APPROVED |
|
Found 11.5 mg caffeine
per daily serving |
|
$0.97 |
|
Genesis Today Pure Green Coffee Bean |
800-2,400 mg GCBE |
"Less caffeine
than ˝ cup of coffee" per 2 capsules (47.5 mg)4 |
APPROVED |
|
|
|
$0.72 to $2.16 |
|
GNC Total Lean™ Metabolic Elite™ (100 mg per
fast-acting tablet, 2 per serving and 1 to 2 per day9)* |
100-200 mg |
100 to 200 mg |
APPROVED |
|
|
|
$0.83 to $1.67 |
|
Labrada Nutrition Green Coffee Bean Extract |
1,050 mg GCBE |
NL |
APPROVED |
|
Found 6.2 mg per
serving (2 capsules) |
|
$0.72 |
|
Life Extension Green Coffee Extract CoffeeGenic™ |
400 to 1,200 mg GCBE |
12 to 24 mg |
APPROVED |
|
|
|
$0.24 to $0.72 |
|
MäritzMayer Laboratories Pure Super Green Coffee Bean
Extract Double Strength |
1,600 mg GCBE |
20 mg |
NOT |
Found only 13.8% of
expected amount of total CGAs |
|
|
$0.69 |
|
Nutri-Fusion Systems Green Coffee Bean
Extract, 800mg |
1,600 mg GCBE |
20 mg |
NOT |
No CGAs and no 5-CQA
found |
No caffeine found |
|
$0.62 |
|
Paradise Herbs, Green Coffee Bean |
400 mg GCBE |
"Less than
2%" (8 mg) |
APPROVED |
|
|
|
$0.23 |
|
Pure Health Naturally Pure Green Coffee Bean |
800 to 2,400 mg GCBE |
NL |
NOT |
Found only 64.2% of
expected amount of total CGAs |
Found 39.8 mg per 2
capsules |
|
$0.43-$1.30 |
|
Pure Health Naturally Pure Green Coffee Bean -
45% Chlorogenic Acids! |
800 to 2,400 mg GCBE |
NL |
APPROVED8 |
|
Found 82.0 mg per 2
capsules8 |
|
$0.43-$1.33 |
|
Reserveage + Advanced Solutions Green Coffee Bean
Extract w/Raspberry Ketones |
400 mg GCBE |
4 mg |
APPROVED |
|
|
|
$0.98 |
|
ResVitále Green Coffee Bean Weight Loss Formula 400mg |
400 mg GCBE |
NL |
APPROVED |
|
Found 9.1 mg per 1
capsule |
|
$0.67 |
|
Starbucks VIA Refreshers COOL LIME with Green
Coffee Extract |
Amount of extract not
listed |
NL |
NA |
Found 81.4 mg of total
CGAs per ˝ packet, suggesting 180 mg of extract** |
Found 35.0 mg per ˝
packet serving |
|
$0.605 |
|
Vitacost Green Coffee Bean Extract 400 mg capsules |
400 to 1,200 mg GCBE |
NL |
APPROVED |
|
Found 7.1 mg per
capsule |
|
$0.20 to $0.59 |
|
Vitamin World Green Coffee Bean Extract |
400 mg GCBE |
24 mg |
APPROVED |
|
|
|
$0.83 |
|
*Tested through CL's Voluntary Certification Program prior
to, at time of, or after initial posting of this Product Review. (Reserveage + Advanced Solutions Green Coffee
Bean Extract w/Raspberry Ketones was added on 11/8/12. CVS and Garden
of Life products were added on 6/3/14. GNC was added
on 12/17/14.) |
|||||||
|
Unless otherwise noted, information about the products
listed above is based on the samples purchased by ConsumerLab.com (CL) for
this Product Review. Manufacturers may change ingredients and label
information at any time, so be sure to check labels carefully when evaluating
the products you use or buy. If a product's ingredients differ from what is
listed above, it may not necessarily be of the same quality as what was
tested. |
|||||||
|
Copyright ConsumerLab.com, LLC, 2012. All rights reserved.
Not to be reproduced, excerpted, linked to, or cited in any fashion without
the express written permission of ConsumerLab.com LLC. |
|||||||
ConsumerTips™:
What to Consider When
Buying:
Look for products in which the extract is claimed to be 45 to 50% total
chlorogenic acids, as this is what has been shown to be effective in
preliminary clinical studies. Some products may list amounts or percentages of
specific chlorogenic acids. In clinically tested products, 10 to 15% has been
the chlorogenic acid called 5-CQA (5-caffeoylquinic acid). The branded green
coffee extracts Svetol® and GCA® contain these amounts.
Keep in mind that many green coffee bean extract supplements do not contain the
amounts of chlorogenic acids claimed on their labels. In addition to the problems exposed in this Review, a
separate analysis of green coffee bean extracts purchased online and in retail
stores in the U.S. (including capsules, soft gels, and packs of powdered
extracts) found that 13 out of 39 products contained less than 50% of
their labeled amounts of chlorogenic acids and, on average, products contained
only 57% of the labeled amounts. (names of the products were not disclosed) (Chen, J Med Food 2019). The only
way to know for sure that the green coffee bean extract product you purchase
contains what it claims is to choose one that has been tested by an independent
third-party, such as ConsumerLab.
Although green coffee extracts contain relatively small amounts of caffeine, Svetol® contains less (under 8 mg per 400 mg dose) than GCA® (8 to 16 mg per 400 mg dose).
What to Consider When Using:
An ideal dosage has not been established. The daily dosage has ranged from 180
to 1,050 mg total intake per day (and 1,200 in the case of the study by Dr.
Oz), but is typically divided into single doses of 200 to 400 mg. It is
generally suggested that green coffee extract be taken with water before a meal
as the product may work by reducing the absorption and utilization of glucose.
Cautions and Concerns:
None of
the clinical trials with green coffee extract have reported any adverse
reactions, although studies have been short-term. As green coffee extract may
impact blood sugar levels, people with diabetes or pre-diabetes
should use it with caution. In addition, some people taking green coffee
extract have experienced slight reductions in blood pressure and heart rate (Vinson, Diab, Met Synd and Obes, 2012),
so people with blood pressure or heart problems should use green coffee extract
with some caution. (Note: Concerns about the design and results of
this study were raised by the FTC in a false advertising lawsuit against
a green coffee bean supplement company.)
Women who are pregnant should be aware that consumption of caffeine
(such as from coffee and soft drinks) during pregnancy is associated with
increased risk of stillbirth, particularly at levels greater than 300mg/day —
the approximate amount in 3 cups of coffee (Heazell, Eur J Obstet Gynecol Reprod Biol 2020).
Moderate caffeine consumption (less than 200 mg per day) does not appear to be
a major contributing factor in miscarriage or preterm birth, according to
the American College of Obstetricians
and Gynecologists.
Information on this site
is provided for informational purposes only. It is not an endorsement of any
product nor is it meant to substitute for the advice provided by physicians or
other healthcare professionals. The information contained herein should not be
used for diagnosing or treating a health problem or disease. Consumers should
inform their healthcare providers of the dietary supplements they take.
Latest Clinical Research Updates for Green Coffee Bean Extract
Supplements
Problems With Green Coffee Bean
4/16/2019
A recently published
analysis found that many green coffee bean extract supplements provided much
lower amounts of key compounds than listed – a finding consistent with ConsumerLab's own Review. For details, see the ConsumerTips section
of the Green Coffee Bean Extract Supplements Review.
Green Coffee Bean Study Retracted
10/21/2014
Evidence for this popular
supplement's effect on weight diminished recently when the authors of a
clinical study admitted that the data was unreliable. The study had been funded
by the maker a popular type of green coffee bean extract. For details, as well
as our tests of these products, see the update in the Green Coffee Bean Supplements
Review >>
Related CL Answers (5)