Menopause Supplements Review (Soy and Red Clover
Isoflavones, Black Cohosh) and Progesterone Creams
Choose the Best Menopause
Supplement. Find Out Now Which Soy Isoflavone, Red Clover, Black Cohosh, and
Progesterone Products Have the Active Compounds You Want!
Medically reviewed and
edited by Tod Cooperman, M.D. 
Last Updated
: 03/06/2019 | Initially Posted:
07/24/2015
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Table of Contents
Summary
·
Do soy isoflavone supplements reduce symptoms of menopause? Soy isoflavones
have a mild estrogenic effect and can modestly reduce menopausal symptoms, such
as hot flashes. Products providing at least 50 mg of soy isoflavones daily or
of specific soy isoflavones (15 mg of genistein or 28 mg of daidzein) may be
important for these effects and require treatment for several weeks before
experiencing improvement. Higher doses are typically used to help maintain bone
density (see Soy Isoflavones -- What It Does).
·
Product labeling typically does not provide details about the
specific forms of isoflavones, but ConsumerLab
determined these from testing, You can check amounts of isoflavones in products
by looking at the 4th column of the Results Table below -- amounts known to
be effective are in bold.
·
Be aware that only about 1/3 to ½ of women may benefit from
isoflavones, depending on whether or not they convert isoflavones into active
forms in their gut (see Soy Isoflavones - What It Is).
·
Do red clover isoflavones reduce symptoms of menopause? Red clover isoflavones
may also have benefit in menopause, particularly in reducing night sweats, but
it is recommended that products provide at least 40 mg daily of total
isoflavones. Both products tested in this review provided this amount or more
(see What CL Found).
·
Black cohosh for menopause? Unlike soy isoflavones, black cohosh
does not have general estrogen-like actions, but may act like estrogen only in
certain places, such as in the brain and the vaginal epithelium, providing no
or modest benefit for symptoms such as hot flashes and vaginal dryness
(see Black Cohosh —What It Does). The frequently
recommended dosage of black cohosh is 20 mg of standardized extract once or
twice a day, manufactured to contain at least 1 mg of triterpenes per day,
although some products provide much larger amounts (see the 2nd and 4th columns in the Results Table below)
and some products, like Remifemin, may
work despite containing no triterpenes.
·
Progesterone for menopause? Progesterone cream may decrease
menopausal hot flashes but does not provide enough progesterone to prevent bone
loss or improve bone density (see Progesterone —What It Does). The progesterone
creams tested by ConsumerLab were found to contain
the amounts of progesterone they claimed (see Progesterone Results Table).
Background:
Changing hormone levels around the time of menopause can trigger
many symptoms in women, including hot flashes, flushing, vaginal dryness, and a
fading sex drive. Such problems are often temporary, but some women suffer for
several years or more. Hormone replacement therapy may ease these symptoms but
carries potential health risks. Popular alternative treatments include
phytoestrogens (from soy, red clover and kudzu), black cohosh, and progesterone
creams. But what are women really getting from these non-prescription menopause
remedies? ConsumerLab.com tested a wide range of products to see what they
really contain, with some often surprising results.
Our report also includes expert advice on selecting and using menopause
products to get the most benefits with the fewest risks. Menopause
typically occurs between the ages of 50 and 52 (McKnight, Am J Obstet Gynecol 2012) although this can vary based on a
number of factors, including genetic differences and family history, ethnicity,
and lifestyle factors such as weight, smoking status and physical activity.
Observational studies suggest that earlier-onset menopause may be associated
with an increased risk of lower bone density, osteoporosis, depression,
cardiovascular disease and premature death, while late-onset menopause may be
associated with a higher risk for breast, ovarian and endometrial cancers (Gold, Obstet Gynecol Clin North Am 2012).
Diet may also influence the age at which menopause occurs.
A study that followed 1,874 British women between the ages of 40 and 65 for four
years found that high intakes of oily fish and fresh
legumes, and higher intakes of vitamin B6 and zinc were associated with a
delayed onset of menopause, while consumption of refined pasta and rice was
associated with an earlier onset. The study found that consumption of 3.5 oz.
of oily fish per day and 2.5 oz of fresh legumes (i.e. green beans, peas,
edamame, fresh lima beans etc.) was associated, respectively, with an
approximate 3-year, and 1-year delay in the onset of menopause, while the
consumption of 7 oz. of refined pasta or rice per day was associated with a 1.5
year earlier onset of menopause (Dunneram, J Epidemiol
Community Health 2018).
Soy and Red Clover Isoflavones:
What It Is:
Phytoestrogens are estrogen-like plant compounds, although they are
considerably weaker than estrogen itself. The most well-studied phytoestrogens
are the isoflavones, particularly those found in soy (Glycine max) and
red clover (Trifolium pratense).
If a woman is already making estrogen on her own, isoflavones can actually
block the hormone by taking up spots in the body's estrogen receptors. This may
help explain why women who eat a lot of soy early in life seem to have a lower
risk of breast cancer. It's also why isoflavones can help ease cyclical mastalgia (breast pain associated with the menstrual
cycle).
In nature, most isoflavones (about 95%) are attached to sugar molecules
(glycosides). Most manufacturers include the weight of the sugar in the stated
amount of isoflavones. In such products, as much as 40% to 50% of the claimed
"total isoflavones" may really be sugar. A more precise label should
state just the weight of the active part of the isoflavones, excluding the
sugar portion of the molecule. These are called "aglycone" (meaning
"without sugar") isoflavones. They may also be referred to by their
specific names. For soy, the aglycone isoflavones are genistein, daidzein, and glycitein. The glycosidic (with sugar) forms are genistin, daidzin and
glycitin. These are also found in red clover
and kudzu. Red clover also includes the glycosidic isoflavones biochanin A and
formononetin, while kudzu contains the glycosidic isoflavone puerarin.
When consumed, the sugar molecules of glycosidic isoflavones are removed in the
intestine by bacterial enzymes and the remainder is converted to the
metabolically active aglycone forms. After this conversion, approximately
one-third of aglycones are absorbed as free isoflavones, and bacteria convert
the other two-thirds to isoflavone metabolites such as equol
and p-ethylphenol, which also get
absorbed into the bloodstream.
Importantly, not all women handle isoflavones the same way. For
example, some do not have the specific gut bacteria necessary to convert
glycosidic isoflavones into aglycones and only about one-third to one-half of
women convert isoflavones to equol. Some, but not
all, evidence suggests that equol-producing women may
enjoy far more benefits from isoflavones, including reduction of menopause
symptoms (Jou,
Int J Gyn Obst 2008).
What It Does:
Much of the clinical and
epidemiological research regarding isoflavones was originally based on intake
of soy-based foods. Soy contains a variety of isoflavones and many other
biologically active compounds, so it is difficult to know which health effects
are attributable to which compounds. More recent studies have focused on
products containing defined amounts of isoflavones.
Soy:
Soy protein (which naturally contains isoflavones) has been associated with
reductions in menopause-related hot flashes. This has been observed, for
example, in Asian cultures where large amounts of soy protein are included in
the diet. In recent years, the effect on hot flashes has been studied using
products standardized to contain specific amounts of isoflavones. A review (Nelson, JAMA 2006) of several studies concluded
that daily use of 50 mg to 70 mg of soy isoflavones reduced the number of hot
flashes by slightly more than one per day on average. In contrast, studies with
hormonal estrogen therapy have shown an average reduction of 2.5 to 3 hot
flashes per day. A pilot study using 120 mg of soy isoflavones (including about
73 mg of genistein and 19 mg of daidzein) showed effects comparable to
conjugated estrogens (Premarin), although the isoflavones took a longer time
(up to 2 months) to have a full effect (Kaari, Maturitas 2006).
Interestingly, a review of soy isoflavone studies by another group (Willamson-Hughes, Menopause 2006) concluded that total
isoflavone content wasn't the most important factor for reducing hot flashes.
Instead, they concluded that a product would help if it provided 15 mg per day
of a specific isoflavone, genistein. A subsequent, large study found that
taking approximately 54 mg of concentrated genistein per day for one year cut
the average number of hot flashes per day from 4.4 to 1.9. Women taking a
placebo enjoyed no such relief (D'Anna, Menopause 2009).
A study using a fermented soy germ product rich in a different soy isoflavone,
daidzein, along with other aglycone isoflavones also showed benefit. Women
given 40 mg per day of daidzein-rich isoflavone aglycones (comprised of 28 mg
daidzein, 4 mg genistein, and 8 mg glycitein) had a
43% reduction in hot flashes after 8 weeks of treatment (compared with a 32%
reduction in the placebo group) and, at 12 weeks, a 52% reduction (39% in the
placebo group). A higher dose (60 mg) offered no additional benefit (Khaodhiar, Menopause 2008).
Giving 12 grams of soy protein twice daily for 16 weeks
to women ages 40 to 60 with menopausal symptoms was found to improve vaginal
dryness in a placebo-controlled study, but it did not have any beneficial
estrogenic effect on the structure of the urogenital tract. Women in the study
who instead, received hormone therapy, experienced improvement in both vaginal
dryness and the structure of the urogenital tract. Both groups experienced
significant improvements in hot flashes and muscle pain, but no improvement in
psychological symptoms or the overall quality of life. The soy protein was
given as a powder in water (each serving providing 26.5 mg of aglycones,
yielding a daily total of 30 mg genistein, 16 mg daidzein, and 7 mg glycitein) (Carmignani, Menopause
2014;Carmignani, Maturitas
2010).
A more recent analysis of 24 clinical studies found that soy
isoflavones (from dietary sources and supplements) were associated with a
modest decrease in hot flashes and vaginal dryness, but not night sweats (Franco, JAMA 2016).
In summary, soy isoflavones can modestly reduce menopausal symptoms, such as
hot flashes. Higher amounts of the specific isoflavones genistein (at least 15
mg/day) or daidzein (28 mg/day) may be important for these effects and require
treatment for several weeks before experiencing improvement.(You
can check amounts of isoflavones in products by looking at the 5th column of
the Results Table below).
Soy protein may slightly lower total cholesterol and LDL while
increasing HDL ("good" cholesterol). This cholesterol-lowering effect
has not been found with isoflavones alone, although soy proteins containing
higher levels of isoflavones seem to have the greatest effect.
Soy isoflavones may also help maintain and even increase bone
density in post-menopausal women, although results have been mixed. A
study funded by the U.S. government found that soy isoflavones can have a
modest effect on reducing calcium loss from bones — although, at best, the
effect is only half that achieved with prescription bisphosphonate
(risedronate) which was shown to increase bone calcium retention by 15%. The
study tested various isoflavone formulations (each taken with meals as 5
tablets daily for 50 days), and, surprisingly, found the most effective to be
low-dose mixed soy isoflavones (from Novasoy® — 105
mg daily of total isoflavones in their natural ratios: genistein 43.5%,
daidzein 42.3% -- which is the isoflavone source, at lower dose, in the One
a Day and Estroven products
in this Review), as compared to a higher dose or formulations with a higher
proportion (83%) of genistein (Pawlowski, Am J Clin Nutr 2015).
The study found no difference in benefit between women whose intestinal
bacteria converted the isoflavone daidzein into equol
and those did not produce equol, although other
research has suggested that bone-building (as well as cholesterol-lowering and
menopausal symptom reduction) benefits occur only in women with the ability to
produce equol (as discussed above).
As noted earlier, soy
isoflavones may help lower the risk of breast cancer, although this
appears to depend on the time of life when used, family history, and whether
the cancer is estrogen receptor-positive or -negative. An 11-year study of seventy-six
thousand French women over 50 years of age found that soy isoflavone use,
overall, was not associated with risk of breast cancer. However, current soy
isoflavone use was associated with a 36% increase in the risk of breast cancer
among those with a family history of breast cancer. In contrast,
among women who were premenopausal (in whom estrogen levels
are still high) or recently menopausal, the risk of developing an
estrogen receptor-positive breast cancer was reduced by half with soy isoflavone
use (Touillaud, Am J Clin Nutr 2019).
Although some research has found soy intake to be associated with a lower risk
of prostate cancer, one study found that men highest dietary intake
of soy isoflavones (0.75 mg to 2.03 mg total soy isoflavones per day) had a
91% increased risk of advanced prostate
cancer compared to those with the lowest intake (0 mg to 0.17 mg total soy
isoflavones per day) (Reger, Int J Cancer
2018).
Red Clover and Kudzu:
Other plants, such as kudzu and red clover, also contain isoflavones. Kudzu (Pueraria
lobata) also contains a unique isoflavone, Puerarin.
This plant has barely been researched. One study found that a kudzu product
containing 100 mg of isoflavones did not relieve most menopausal symptoms but
did improve cognitive function in menopausal women (Woo, Menopause 2003).
There is also one small study suggesting that isoflavones from a related
plant, Pueraria mirifica (also known
as Kwao Krua), have some
potential for treating menopausal symptoms (Chandeying, J Med
Assoc Thai 2007). Some studies suggest that red clover
isoflavones can ease menopausal symptoms, but results have varied. An average
reduction of only 1/2 of a hot flash per day has been shown (Nelson, JAMA 2006), which is somewhat lower
than that found with soy isoflavones. An analysis which included 7 clinical
trials on the effects of red clover found red clover was not associated with an
improvement in hot flashes, but was associated with improvement in night sweats
(Franco, JAMA 2016). Red
clover may also help maintain the density of the bone in the lower spine in
both menopausal and peri-menopausal women, although not post-menopause. Red
clover isoflavones have not shown a beneficial effect on cholesterol, although
both red clover and soy isoflavones may improve the elasticity of blood vessels
in menopausal and peri-menopausal women.
Ipriflavone:
A semi-synthetic form of isoflavone, called ipriflavone,
is also available in some supplements. It was chemically designed to provide
the bone-stimulating effect of isoflavones without any other estrogen-like
actions. However, one study found no significant reduction in bone loss in
post-menopausal women taking ipriflavone. The
compound might have also been responsible for a reduction in certain white
blood cells among study participants (Alexandersen, JAMA
2001). Ipriflavone is not intended for
the treatment of menopausal symptoms, but, similarly, is not believed to
adversely affect estrogen receptor-positive breast cancer (Petilli, Calcif Tissue Int 1995). Ipriflavone
products were not included in this review.
Quality Concerns:
The labeling of isoflavone supplements can be confusing. The potential potency
of two products claiming the same amount of isoflavones can differ
significantly depending on how the manufacturers choose to calculate the
amount. If the "aglycone" form is not specified, about 50% of the
amount listed may actually be sugar naturally attached to the isoflavones. Most
of the products tested in this review listed only total isoflavones and not specific
isoflavones — which can be important. (See ConsumerTips™ for
more information on how to read and interpret labels on isoflavone products, as
well as a list of common soy-based foods and their aglycone isoflavone levels.)
Isoflavone products were tested for their total and specific forms of
isoflavones. Products were also tested to make sure they did not contain
significant amounts of lead, cadmium or arsenic We also tested tablets to see
if they could properly break apart.
Black Cohosh:
What It Is:
Black cohosh (Cimicifuga racemosa) is
a member of the buttercup family. The roots and rhizomes are often used in
supplements. (See ConsumerTips™ for
information about what to look for in black cohosh products).
What It Does:
Black cohosh is most often used for the treatment of menopausal symptoms. The
evidence appears to be mixed: while some studies suggest the herb may modestly
reduce hot flashes, relieve vaginal dryness, and possibly protect the bones
from osteoporosis, an analysis which included 16 clinical trials on the effects
of black cohosh found no benefit for symptoms of menopause (Franco, JAMA 2016).
Unlike isoflavones, black cohosh does not have general estrogen-like actions.
Rather, it may act like estrogen only in certain places: the brain/hypothalamus
(reducing hot flashes), bone (potentially fighting osteoporosis), and vaginal
epithelium (reducing vaginal dryness).
Black cohosh may be helpful for reducing menopausal
symptoms in women with fibroids who wish to avoid hormone
replacement drugs. In a clinical study of women with menopausal symptoms who
also had fibroids, daily supplementation with 40 mg of a branded black cohosh
supplement (Remifemin — see the Quality
Concerns section below for more about this product) for 3 months significantly
improved menopausal symptoms and modestly reduced the size of fibroids (median
decrease of 30%) (Xi, Evid Based Complement Alternat
Med 2014). Women in the study who did not take black cohosh but took
the hormone-replacement drug tibolone also had a significant improvement in
menopausal symptoms, but experienced a slight increase in fibroid size.
Black cohosh has also been tried for reducing hot flashes in women who have
undergone surgery for breast cancer, but it does not appear to be effective for
this purpose. Although sometimes recommended for PMS and pain associated with
menstruation, there is no meaningful evidence that it helps women with these
conditions.
A study of women with unexplained infertility being treated with the fertility
drug clomiphene found that adding black cohosh extract (120 mg /day) to their
treatment improved pregnancy rates (Shahin, Repro Biomed Online 2007).
Quality Concerns:
Because the active components of black cohosh have not yet been identified,
it's hard to say which products are likely to work better than others. Compounds
called triterpene glycosides are found in black cohosh and are often used to
verify the amount of the herb in a product, although it is unclear whether they
have a specific effect on the body. It is believed that products made from
extracts should contain at least 2.5% triterpene glycosides, but levels vary
across brands, and it's not known if more is really better. Non-extracts (also
called "root powders" or "whole herb") may contain a lower
concentration of triterpenes, although the daily dose typically provides at
least 1 mg of total triterpenes.
The most clinically studied black cohosh product, Remifemin,
has been reformulated over the years, and the percentage of triterpene
glycosides was previously unknown. However, in this review, ConsumerLab.com
tested Remifemin and other black
cohosh products for amounts of triterpene glycosides.
Products were tested to make sure they did not contain significant amounts of
lead, cadmium or arsenic We also tested tablets to see if they could properly
break apart. See ConsumerTips™ for more information about black
cohosh.
Progesterone Cream:
What It Is:
Progesterone is one of the two primary female hormones. For use as a drug or
topical cream, progesterone is synthesized from chemicals found in soy or
Mexican yam (Dioscorea villosa).
[Note: Mexican yam neither contains nor can directly provide you with
progesterone, despite claims you may read.] Because it is chemically identical
to the progesterone a woman makes naturally, this synthesized version is often
called a bioidentical hormone. Progesterone can be absorbed to some extent
through the skin, which is why it is sold as a cream. Higher doses of
progesterone are taken orally on a prescription basis in the form of progestin,
such as in oral contraceptives.
What It Does:
Although the evidence is
mixed, use of progesterone cream may decrease menopausal hot flashes but does
not provide enough progesterone to prevent bone loss or improve bone density.
Creams also do not seem to lower the risk of uterine cancer, a possible
complication of estrogen therapy.
Quality Concerns:
Because progesterone in creams is synthetic, improperly manufactured products
could potentially contain manufacturing by-products, such as androstenedione,
another steroid.
Tests Performed:
Neither
the FDA nor any other federal or state agency routinely tests supplements for
quality prior to sale. ConsumerLab.com, as part of its mission to independently
evaluate products that affect health, wellness, and nutrition, purchased many
soy and/or red clover-containing isoflavone supplements, black cohosh
supplements, and progesterone creams sold in the U.S. Isoflavone and black
cohosh products were tested for possible contamination with lead, cadmium and
arsenic. All non-chewable and non-time-release tablets or caplets were also
tested for their ability to break apart properly. Isoflavone products were
additionally tested for the type and quantity of their isoflavones. Black
cohosh supplements were tested for their amount of triterpene glycosides. Progesterone
creams were tested for their amount of progesterone. See Methods and Passing Score for more
information.
What CL Found:
Soy and Red Clover
Isoflavones:
All of the soy and/or red clover isoflavone-containing products selected by
ConsumerLab.com for testing contained their claimed amounts of isoflavones, as
did two additional products evaluated through ConsumerLab.com's
voluntary Quality Certification Program.
However, amounts of isoflavones in products varied, as shown in the table
below, and this variation may impact their effectiveness.
None of the tested products listed their total amounts of particular
isoflavones (e.g., genistein/tin) in their Supplement Facts, nor did they
specify the amounts of isoflavones in the aglycone form, although they did list
their amount of total isoflavones. This is somewhat helpful, but keep in mind
that isoflavone amounts listed this way include the sugar molecules attached to
many of the aglycone isoflavones. You'll generally need to reduce those numbers
by about half to estimate the true amounts of genistein or daidzein.
How to Choose an Isoflavone Supplement
As discussed above, the ideal amounts of isoflavones needed to reduce
menopausal symptoms have yet to be established. Furthermore, the benefits of a
product may depend on the gut microflora of the individual using it. However,
there are a few criteria based on clinical research that may be helpful in
choosing an isoflavone supplement.
·
As noted earlier, 15 mg or more daily of the isoflavone
genistein from soy may be necessary for treating hot flashes. In the
fourth column of the table below, we show the amounts of genistein and other
aglycone isoflavones in each of the products. We have listed in bold amounts of
genistein that meet or exceed this 15 mg level. [Note: This level of genistein is
based on the aglycone form which excludes the weight of any attached sugar
molecules. Sugars nearly double the weight of isoflavone compounds and are
often included in amounts shown on labels that area listed as "genistein/tin".]
Three of the products provided at least 15 mg of genistein, suggesting that
they may be effective for treating hot flashes and other menopausal symptoms:
·
Bayer One A Day Menopause Formula (20.1 mg of
genistein)
·
Spring Valley Soy Isoflavones (32.1 mg of genistein)
·
Estroven Maximum Strength (21.6 mg of
genistein)
·
Two products provided at least 24 mg of daily of
daidzein from soy, which one study suggests may be effective —
although neither is a fermented soy product like the one in the study, so the
isoflavones may not be as bioavailable, as fermentation increases isoflavone
bioavailability:
·
Options Healthy Woman Soy Menopause Supplement (50.9 mg of
daidzein)
·
Whole Food Soy Isoflavones (50.3 mg of daidzein)
·
Many products shown to work in clinical trials provided 50
mg to 120 mg of total isoflavones daily. It's hard to know how much of this
was in the active aglycone form and how much is the attached sugars. However,
it is perhaps currently the most useful general guideline when reading labels,
since nearly all products list total isoflavone levels and few specifically
disclose amounts of aglycone isoflavones or amounts of specific isoflavones. In
the second column in the table below, we show the total isoflavones in each
product. Those with daily amounts in the 50 mg to 120 mg range are shown in
bold. Interestingly, all of the products mentioned above that provide a daily
dose of at least 15 mg of genistein or 28 mg of daidzein also provided total
isoflavones in this range.
·
Bluebonnet Non-GMO Soy Isoflavones and a combination
product, Solgar Black Cohosh Root
Extract Plus, were the only products which did not provide
levels of genistein, daidzein, or total isoflavones at or above those shown to
work in clinical trials.
·
It's generally recommended that red clover supplements
provide at least 40 mg daily of total isoflavones (several of which
are the same as those in soy). This is the amount (which includes attached
sugar molecules) that is associated with some effect on reducing hot flashes
(Nelson 2006). Both red clover only supplements tested
in this review provided this amount, with Promensil
Menopause providing 40 mg of total isoflavones per tablet and Swanson
Superior Herbs High-Potency Red Clover Extract providing 50 mg per
capsule.
None of the tested
products listed their total amounts of particular isoflavones (e.g.,
genistein/tin) in their Supplement Facts, nor did they specify the amounts of
isoflavones in the aglycone form. This is somewhat helpful, but keep in mind
that isoflavone amounts listed this way include the sugar molecules attached to
many of the aglycone isoflavones. You'll generally need to reduce those numbers
by about half to estimate the true amounts of genistein or daidzein. We did the
calculations for you, as shown in the fifth column of the table below.
Occasionally, isoflavones products may include plant enzyme blends, such as the
trademarked Isolase, which are designed to help the
body remove the sugar molecule from the isoflavones and increase absorption.
According to its manufacturer, Isolase has been shown
to double the absorption of sugar-bound isoflavones. However, none of the
products in the current review contain enzymes.
See ConsumerTips™ for
Soy and Red Clover Isoflavones for more information about isoflavones.
Black Cohosh Supplements:
One black cohosh product, Natures Way
Black Cohosh Root, , failed to pass this review because it was
contaminated with 1.7 mcg of lead per daily serving, slightly above the limit
permitted by ConsumerLab.com (see How Products Were Evaluated). Nature's
Way was the only product tested that was made from only from root
powder, as opposed to root extract. This may help explain the higher level of
lead, as the extraction process generally removes heavy metals while
concentrating other compounds. The lead in this product is probably not
dangerous in itself but represents unnecessary exposure to this heavy metal
which is toxic at much higher levels (3 mcg per day in children and 12.5 mcg
per day in adults -- previously higher limits were lowered by the FDA in
2018).
There remains scientific uncertainty over the chemical constituents of black
cohosh and even greater uncertainty as to which compounds represent its active
components. One of the potential marker compounds of black cohosh is triterpene
glycosides, and some products list their amounts of these. Consequently,
ConsumerLab.com tested black cohosh products for levels of these compounds.
The two products which listed triterpene glycoside levels, Oöna For Menopause and Solgar Black Cohosh Root Extract Plus each
contained their listed amounts (4.5 mg per 3 tablets of Oöna
and 5 mg in one capsule of Solgar).
Higher amounts were found in Nature's Bounty Black Cohosh (7.1
mg per capsule), Nature's Way Black Cohosh Root (19.4 mg per 3
capsules), and Rexall Black Cohosh (7.8 mg per capsule), Estroven contained much less (1.5 mg per
capsule) and Remifemin contained
none. However, as noted earlier, there is clinical evidence supporting the use
of Remifemin, so the amount of triterpene glycosides
was not a basis for approving this product. Otherwise, black cohosh products
listed as Approved are those that contained their listed amounts of triterpene
glycosides (and a minimum of 0.4% triterpene lactones in root/rhizome products)
and the compound cimifugin must not be present at
above 0.1 mcg per gram, as its presence signifies adulteration with an
incorrect species. All black cohosh products had to meet CL's criteria for
purity from heavy metals and for proper disintegration of tablets.
See ConsumerTips™ for
Black Cohosh for more information about black cohosh.
Progesterone Cream:
Both progesterone creams contained their claimed amounts of progesterone. Each
provided about 40 mg of progesterone in the suggested application size (about
one teaspoon, or 4.2 grams of cream), although Emerita Pro-Gest contained
slightly less progesterone per gram of cream than Source Naturals
Natural Progesterone Cream. Each product included additional ingredients,
such as aloe vera and various oils; Source Naturals Natural
Progesterone Cream also contained small amounts of grapefruit seed and
ginseng root extracts. The least expensive product was Source Naturals
Natural Progesterone Cream, which cost 16 cents for each 20 mg of
progesterone. See ConsumerTips™ for
Progesterone Cream more information about progesterone cream.
Test Results by Product:
Listed
below are the test results for 16 products -- 14 dietary supplements and two
progesterone creams. Twelve were selected by ConsumerLab.com and four (each
indicated with a CL flask) were tested at the request of their
manufacturers/distributors through ConsumerLab.com's
voluntary Quality Certification Program. Also listed are
two products similar to ones that passed testing but are sold under different
brand names. Products are grouped by ingredient and appear alphabetically
within these groups. Also shown are the labeled serving sizes and claimed
amounts of the key ingredients. If amounts of specific isoflavones or
triterpene glycosides were not labeled, amounts found in testing are shown.
Products that did not meet ConsumerLab.com's
standards are listed as Not Approved with an explanation of the problem(s)
found. The full list of ingredients is available for each product by clicking
on "Ingredients" in the first column. For more information about
testing go to How Products Were Evaluated.
|
RESULTS OF CONSUMERLAB.COM TESTING OF SOY,
RED CLOVER AND/OR BLACK COHOSH SUPPLEMENTS |
||||||
|
Product Name, Serving
Size, and Suggested Daily Serving on Label |
Claimed Amount of
Isoflavones (Aglycone) and/or Triterpene Glycosides Per Suggested Daily
Serving on Label* |
--TEST RESULTS-- |
Cost for Daily
Suggested Serving on Label |
|||
|
OVERALL RESULTS: |
Contained Listed
Amounts of Isoflavones (Aglycone) and/or Triterpene Glycosides (Or Found
Amounts, If There Is No Listed Amount)* |
Did Not Exceed
Contamination Limits for Lead, Cadmium and Arsenic |
Disintegrated
Properly |
|||
|
Soy Isoflavones Only Supplements: |
||||||
|
|
60 mg |
APPROVED |
|
|
|
$0.34 |
|
|
40 mg |
APPROVED |
|
|
NA |
$0.33 |
|
|
55 mg |
APPROVED |
|
|
|
$0.24 |
|
|
80 mg |
APPROVED |
|
|
|
$0.22 |
|
|
50 mg |
APPROVED |
|
|
NA |
$0.57 |
|
Red Clover Only Supplements: |
||||||
|
|
40 mg |
APPROVED |
|
|
|
$0.90 |
|
|
50 mg to 100 mg red
clover isoflavones |
APPROVED |
|
|
NA |
$0.22-$0.43 |
|
Black Cohosh Only Supplements: |
||||||
|
|
540 mg |
APPROVED |
Found 7.1 mg
triterpene glycosides per daily serving |
|
NA |
$0.09 |
|
|
1,620 mg |
NOT |
Found 19.4 mg
triterpene glycosides per daily serving |
Found 1.7 mcg lead per
daily serving (1.06 mcg per g) |
NA |
$0.21 |
|
|
180 mg to 360 mg |
APPROVED |
|
|
|
$0.62-$1.25 |
|
|
40 mg |
APPROVED± |
No triterpene
glycosides found± |
|
|
$0.32 |
|
|
540 mg |
APPROVED |
Found 7.8 mg
triterpene glycosides per daily serving |
|
NA |
$0.05 |
|
Similar to Tested Products**: |
||||||
|
Puritan's Pride® Black Cohosh (1 capsule, once
daily) |
Similar to Nature's Bounty® Black Cohosh. |
$0.14 |
||||
|
Vitamin World® Black Cohosh (1 capsule, once
daily) |
Similar to Nature's Bounty® Black Cohosh. |
NA6 |
||||
|
Combination Products: |
||||||
|
|
Does not list amounts
of soy isolflavones or black cohosh root in "Estroven herbal relief blend" |
APPROVED |
Found 64.2 mg
soy isoflavones and 1.5 mg triterpene glycosides per daily serving |
|
NA |
$0.68 |
|
|
4 mg to 8 mg |
APPROVED |
|
|
NA |
$0.34-$0.69 |
|
|
||||||
|
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, 2015. All rights reserved.
Not to be reproduced, excerpted, or cited in any fashion without the express
written permission of ConsumerLab.com LLC. |
||||||
|
RESULTS OF
CONSUMERLAB.COM TESTING OF PROGESTERONE CREAMS |
|||||
|
Product Name, Serving
Size, and Suggested Daily Serving on Label |
Claimed Amount of
Progesterone Per Suggested Daily Serving on Label |
--TEST RESULTS-- |
Cost for Daily
Suggested Serving on Label |
||
|
OVERALL RESULTS: |
Contained Listed
Amounts of Progesterone |
||||
|
|
40 mg2 |
APPROVED |
|
$1.742 |
|
|
|
44 mg to 88 mg |
APPROVED |
|
$0.35-$0.71 |
|
|
1 Not
tested but claimed on label. 3 This
product is not defined as a dietary supplement, according to the FDA. See the
agency's 2016 warning for more
information. |
|||||
|
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, 2015. All rights reserved.
Not to be reproduced, excerpted, or cited in any fashion without the express
written permission of ConsumerLab.com LLC. |
|||||
ConsumerTips™:
Soy and Red Clover Isoflavones:
When Buying:
As noted earlier (see Soy and Red Clover Isoflavones: What It Is),
manufacturers currently use a variety of ways to describe the isoflavone
content of their products, so consumers must understand some of the technical
terminology and read labels carefully.
The term "isoflavone" can refer to either just the estrogen-like
aglycone (meaning "without sugar") isoflavone or to a larger molecule
that includes the molecule linked to a sugar molecule (together referred to as
a glucosidic isoflavone or isoflavone glycoside).
Nearly all products contain a mixture of both forms. However, some products
specifically declare the weight of the active "aglycone" isoflavone
in the product, while most include the weight of the attached sugar molecules,
resulting in uncertainty over the amount of aglycone isoflavone to be expected
in a product. The aglycone isoflavones may also be referred to by their
specific names, which, for soy, are genistein, daidzein, and glycitein (note that all three end
with the letters "ein") and, for red
clover, also include biochanin A, and formononetin. Similarly, the larger,
sugar-containing, glycosidic isoflavones can be referred to by their specific
names, e.g., genistin, daidzin,
and glycitin (all ending in "in").
The relative amounts of the isoflavones depend on their source. For example, in
soy bean (the source of the concentrate in the branded ingredient Novasoy® used the One a Day and Estroven products in this Review), genistein is
the predominant type, representing about 50% of total isoflavones. In soy germ
(which is a smaller, isoflavone-dense part of the soybean) daidzein is more
common while genistein is less than 20% of the total. Soy germ is the source of
the concentrate in the branded ingredient SoyLife. As
discussed below, debate remains over the medical significance of the isoflavone
ratios and amounts.
Dosage:
As noted earlier, the optimal dose and type of isoflavones needed to reduce hot
flashes has not been firmly established. One review of clinical studies (Nelson
2006) suggested aiming for a total daily amount of 50 mg to 70 mg of soy
isoflavones. Another review of clinical studies (Williamson-Hughes 2006)
suggested that at least 15 mg per day specifically of the isoflavone genistein
(calculated in aglycone equivalents, i.e., without the sugar molecules) is
needed, with the total amount of isoflavones being less important -- although
one study suggests that 28 mg per day of daidzein may also work (Khaodhiar 2008). For red clover (for which the evidence of
efficacy is weaker), the generally recommended daily dosage for treating
symptoms of menopause is 40 mg of red clover isoflavones.
Bear in mind that isoflavone research continues, and it remains possible that
other components of soy may play a role in its effects on the body.
For maintaining and/or increasing bone density in post-menopausal women, higher
amounts of isoflavones are typically used than for reducing hot flashes. The
large Osteoporosis Prevention Using Soy (OPUS) study found increased bone
density with 120 mg per day of isoflavones after both one and two years of
treatment but not at a lower dose of 80 mg (Wong 2008). However, bone density
in critical areas such as the lower back and hip were not increased. The
isoflavone product tested in the OPUS study was a soy germ concentrate
relatively low in genistein (under 10%) relative to daidzein (over 30%). A
similar amount of soy isoflavones (105 mg per day from Novasoy®,
taken as 5 tablets with meals) also showed a 7.5% improvement in bone calcium
retention (Pawlowski, Am J Clin Nutr 2015).
A small study of genistein alone (54 mg per day) showed increased bone density
in the lower back and hip in postmenopausal women (Marini 2007). Lower doses of
isoflavones do not seem to be as effective, although bone density has been
shown to be higher among women in Asia who consume roughly 50 mg of isoflavones
per day than among those consuming less.
For lowering cholesterol, specifically LDL levels, isoflavones alone may not be
very helpful, but substituting soy protein for other sources of protein may
provide a modest benefit.
As it may be helpful to maintain a more constant level of the isoflavones in
one's body, it makes sense to divide the daily dose into at least two servings
per day if possible. In addition, taking isoflavones with a meal high in
carbohydrates may help with absorption.
Getting isoflavones from foods:
If you are interested in getting your isoflavones directly from foods, look for
foods and beverages made from soy protein. Listed below are examples of
soy-based foods and general estimates of their estrogen-like
"aglycone" isoflavone content per 100 grams (equal to a bit less than
a quarter pound). Be aware that soy oils and soy lecithin are devoid of
isoflavones, and soy sauce contains only a very small amount.
|
Food: |
Isoflavones (aglycone) per 100 grams |
|
Soy flour (roasted) |
199 mg |
|
Soy flour (textured) |
148 mg |
|
Soy beans dry roasted |
128 mg |
|
Soy protein concentrate (aqueous washed) |
102 mg |
|
Soy protein isolate |
97 mg |
|
Soy beans cooked and boiled |
55 mg |
|
Tempeh |
44 mg |
|
Miso |
43 mg |
|
Tofu |
31 mg |
|
Soybean curd cheese |
28 mg |
|
Soy protein concentrate (produced by alcohol
extraction) |
12 mg |
|
Soy milk (3.4 fl oz) |
10 mg |
|
Soy noodles |
9 mg |
|
Vegetable protein burger |
8 mg |
·
While soy products are generally considered safe, there is
concern that soy isoflavones may not be safe for women with an existing
estrogen receptor-positive breast cancer or with a family
history of breast cancer. They are also not recommended for pregnant
or nursing women. Most studies have found that isoflavones do not stimulate
uterine cells, but one large study found stimulation in about 3% of women,
possibly indicating a slightly increased risk of uterine cancer with high-dose
isoflavone use (Unfer, Fertil Steril 2004).
·
Individuals with impaired thyroid function should be aware that
soy isoflavone intake might affect thyroid function, potentially increasing
the dose of thyroid hormone required (Messina, Thyroid 2006).
·
Be aware that even in people without thyroid disease, soy
isoflavones may cause temporary increases in thyroid hormone levels.
A study in adults with normal thyroid function that found consuming 15 grams of
soy protein containing approximately 33 mg of aglycone soy isoflavones daily
(as estimated based on a daily dose of 66 mg total isoflavones) increased
levels of rT3 (reverse tri-iodothyronine) and TSH (thyroid stimulating
hormone), and decreased levels of fT4 (free thyroxine) after three months of
supplementation. However, levels returned to normal after six months of
supplementation (Sathyapalan, Front Endocrinol 2018).
·
People with allergies or hypersensitivity to
soy products may have a similar reaction to products containing isolated soy
isoflavones.
·
It is not recommended that individuals consume excessive amounts
of isoflavones based on animal research that indicated possible negative
consequences, such as reduced fertility.
·
Gastrointestinal side-effects may occur in some people taking
isoflavone supplements.
Black Cohosh:
When Buying:
Be sure that the product is made from black cohosh and not blue cohosh which
can cause serious side-effects. The product should be made from the root and/or
rhizome of the black cohosh plant. It is not known which of the constituents of
black cohosh may be responsible for its effects on menopausal symptoms. Generally extracts are standardized to contain at least 2.5%
triterpene glycosides (a group of naturally occurring compounds found in black
cohosh) or to deliver at least 1 mg of these triterpenes per daily dose. However,
research suggests that triterpene glycosides may not be the active compounds.
If you are interested in getting a specific amount of
triterpenes from a black cohosh product, it is important that you distinguish
between black cohosh extracts and those labeled as whole herb or root powder.
Extracts are generally more concentrated forms of the herb, so you will need
less extract than whole herb to yield the same amount
of triterpenes and other phytochemicals.
Dosage:
The frequently recommended dosage of black cohosh is 20 mg of standardized
extract once or twice a day, manufactured to contain at least 1 mg of
triterpenes per day. (However, one placebo-controlled study suggests that a
daily dose of just 6.5 mg of a black cohosh extract standardized to 1.8% to
2.7% of the triterpene lactone 27-deoxyactein may also be effective; although
the researchers purchased this product in a pharmacy in Iran and did not
analyze the contents (Mohammad-Alizadeh-Charandabi,
Chinese Medicine 2013). This product is sold as Cimifugol,
and does not appear to be available in the U.S.) Treatment for 4 weeks is
usually required before there is significant improvement in symptoms.
Concerns and Cautions:
·
Black cohosh may cause gastrointestinal upset. Other potential
adverse effects include rash, headache, dizziness, weight gain, feeling of
heaviness in the legs, and cramping.
·
Because of potential hormonal interaction, black cohosh is not
recommended for adolescents or pregnant or nursing women. Similarly, it is not
recommended for women with existing breast cancer or with a high risk of
developing breast cancer.
·
Black cohosh has been found to slightly lower blood pressure and
blood sugar in certain animals. Although these effects haven't been reported in
people, black cohosh could potentially interact with drugs for high blood
pressure or diabetes. Black cohosh may cause significant interactions if taken
with ACE inhibitors, angiotensin receptor blockers (ARBs) or amiodarone (Page, Circulation 2016).
·
There are several reports of black cohosh-containing products
causing severe liver injury or autoimmune hepatitis (see listing in the NIH LiverTox database).
However, it is not clear whether the cause was black cohosh itself, or a
contaminant present in the product. Nevertheless, in February 2006, New Zealand
announced a requirement that black cohosh sold in that country carry a warning
stating, "black cohosh may harm the liver in some individuals. Use under
the supervision of a healthcare professional". (See 2/15/06 posting
in Recalls and Warnings). In addition, in June
2007 a USP expert committee voted to require the following cautionary statement
to appear on the labels for black cohosh products: Caution: In rare
cases black cohosh has been reported to affect the liver. Discontinue use and
consult a healthcare practitioner if you have a liver disorder or develop
symptoms of liver trouble, such as abdominal pain, dark urine, or jaundice. (See
6/27/07 posting in Recalls and Warnings).
Progesterone Cream:
When Buying:
Be aware that different products may contain different concentrations of
progesterone. In this review, the amount of progesterone ranged from about 16
to 25 mg per gram of cream (amounts noted in the table). You'll be able to use
less cream if a product is more concentrated, so factor this in when comparing
prices.
Dosage:
The amount shown to work in a clinical trial was 20 mg of progesterone from
cream applied daily to the skin, such as the upper arms, thighs, or breasts.
Users are advised to vary the location from day to day. All the products in
this review provide 20 mg of progesterone within their suggested dosage ranges.
It is not known whether higher doses will be more effective.
It is sometimes suggested that users discontinue use for about one week each
month.
Concerns and Cautions:
·
Even though progesterone is sold as a topical cream or cosmetic
product, it is a hormone. It is recommended that it not be
used except under physician supervision.
·
Oral progesterone protects the uterus from the stimulating
effects of unopposed estrogen. However, standard doses of progesterone cream
probably provide too little progesterone to serve this purpose.
·
Progesterone cream may cause light spotting, but is unlikely to
cause other side effects associated with oral progesterone.
·
Extremely small amounts (less than 0.01 mg per gram of cream) of
the hormone precursor androstenedione may occur in progesterone products, most
likely as a manufacturing by-product. This should not be of medical concern.
However, androstenedione in much higher doses (about 100 mg per day or more)
has been used as an athletic performance enhancer. Consequently,
androstenedione is banned among Olympic athletes and its presence in the body
can cause disqualification from competition.
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 Menopause Supplements
Soy Isoflavones & Breast Cancer Risk
3/06/2019
Soy isoflavones, which
have estrogen-like effects, are used by women hoping to reduce menopausal
symptoms. A new study suggests this use may raise the risk of
breast cancer in some women but lower it in others. For
details, see the What It Does section of the Soy
Isoflavone Supplements Review.
11/20/2018
Daily intake of soy
isoflavones (as found in soy protein and soy isoflavone supplements) can affect
thyroid hormone levels — even in people with normal thyroid function, according
to a recent study. For details, see the "Concerns and Cautions"
section of the Menopause Supplements Review and
the Protein Supplements Review.
11/20/2018
Daily intake of soy
isoflavones (as found in soy protein and soy isoflavone supplements) can affect
thyroid hormone levels – even in people with normal thyroid function, according
to a recent study. For details, see the "Concerns and Cautions"
section of the Menopause Supplements Review and
the Protein Supplements Review.
5/05/2018
A new study found that
diet may influence the age at which menopause occurs in women. This is
important because later menopause has been associated with lower risk of many
health conditions. Find out which foods are associated with later or earlier
menopause in the Background section
of the Menopause Supplements Review. (Also see what we found in
supplements intended to treat menopause symptoms.)
Which Menopause Supplements Really Work?
6/25/2016
Certain supplements may
be better than others for hot flashes, vaginal dryness or night sweats
according to a recent analysis of clinical studies. Get the details for soy, red clover and black cohosh in the
"What It Does" section of the Menopause Supplements Review
>>
Related CL Answers (9)