{"id":26813,"date":"2019-12-10T14:30:28","date_gmt":"2019-12-10T22:30:28","guid":{"rendered":"https:\/\/selfhacked.com\/?p=26813"},"modified":"2021-09-20T09:18:20","modified_gmt":"2021-09-20T16:18:20","slug":"l-lactis","status":"publish","type":"post","link":"https:\/\/selfhacked.com\/blog\/l-lactis\/","title":{"rendered":"Top 8 Health Benefits of Lactococcus lactis (L. lactis)"},"content":{"rendered":"

L. lactis<\/em> is a commonly used probiotic whose health benefits we are just beginning to understand. This bacterium boosts the immune system, may combat allergies, hypertension, and IBD, and has beneficial effects on the skin.<\/p>\n

<\/p>\n

<\/a>What is L. lactis<\/em>?<\/strong><\/span><\/h2>\n

Lactococcus lactis<\/em> is a lactic acid-producing<\/a> Gram-positive species of bacteria used extensively in the production of buttermilk, cheese, pickled vegetables, and other fermented products.<\/p>\n

L. lactis<\/em> is often studied as a genetically modified organism for the treatment of animal (R<\/a>, R<\/a>, R<\/a>, R<\/a>, R<\/a>, R<\/a>) and human diseases (R<\/a>). Its health benefits as a probiotic, however, are not as well-known or researched.<\/p>\n

Note that this post is about Lactococcus lactis<\/em>. For more information about the bacterium formerly known as Lactobacillus lactis<\/em>, check out this post on L. delbrueckii<\/em><\/a>.<\/p>\n

<\/a>Antioxidant Properties<\/strong><\/span><\/h3>\n

Exopolysaccharide (EPS) of L. lactis<\/em> increased catalase<\/a>, superoxide dismutase<\/a> (SOD<\/a>) and glutathione<\/a> peroxidase<\/a> (GSH<\/a>-Px) activity, and decreased malondialdehyde (MDA) levels in mice (R<\/a>).<\/p>\n

<\/a>Potential Benefits of L. lactis<\/strong><\/span><\/h2>\n

L. lactis<\/em> probiotic supplements have not been approved by the FDA for medical use and generally lack solid clinical research. Regulations set manufacturing standards for them but don’t guarantee that they’re safe or effective. Speak with your doctor before supplementing.<\/p>\n

<\/a>Insufficient Evidence For<\/span><\/h3>\n

The following purported benefits are only supported by limited, low-quality clinical studies. There is insufficient evidence to support the use of L. lactis<\/em> for any of the below-listed uses. Remember to speak with a doctor before taking L. lactis<\/em> probiotic supplements, and never use them in place of something your doctor recommends or prescribes.<\/p>\n

<\/a>1) Skin Health<\/h4>\n

Ingestion of milk fermented with L. lactis<\/em> increased sebum production, thereby potentially reinforcing the skin barrier in 23 healthy young women (R<\/a>).<\/p>\n

Ingestion of heat-killed L. lactis<\/em> also maintained skin hydration and improved subjective skin elasticity in 30 middle-aged Japanese women (R<\/a>).<\/p>\n

<\/a>Animal & Cell Research (Lacking Evidence)<\/span><\/h3>\n

No clinical evidence supports the use of L. lactis<\/em> for any of the conditions listed in this section. Below is a summary of the existing animal and cell-based research, which should guide further investigational efforts. However, the studies listed below should not be interpreted as supportive of any health benefit.<\/p>\n

<\/a>2) Immunity<\/h4>\n

Yogurt fermented with L. lactis<\/em> activated plasmacytoid dendritic cells (pDC), that are important for both innate and adaptive immune responses (R<\/a>, R<\/a>), and susceptibility to infection (R<\/a>).<\/p>\n

It activated natural killer (NK) cells and enhanced their cytotoxic activity (R<\/a>).<\/p>\n

It improved resistance against pneumococcal infection, possibly by improving pathogen lung clearance, reduces lung injuries and increases the survival of infected mice (R<\/a>, R<\/a>).<\/p>\n

L. lactis<\/em>-fed mice have drastically improved survival rate, reduced weight loss<\/a>, and reduced lung damage when infected by murine parainfluenza virus (mPIV1) (R<\/a>) or the H1N1 influenza virus (R<\/a>).<\/p>\n

Kefir<\/a>-isolated L. lactis<\/em> protect cells from C. difficile<\/em> toxins (R<\/a>).<\/p>\n

<\/a>3) Allergies<\/h4>\n

Both live and heat-killed L. lactis<\/em> reduced the severity of allergic response in mice (R<\/a>, R<\/a>, R<\/a>).<\/p>\n

It decreased the Th2<\/a> response (R<\/a>) and induces a Th1<\/a>-polarizing program in dendritic cells in mice (R<\/a>).<\/p>\n

It significantly attenuates atopic esophageal and bronchoalveolar eosinophilic inflammation in mice (R<\/a>).<\/p>\n

Ethanol can increase allergic responses. L. lactis<\/em> was shown to restore oral tolerance<\/a> in mice, by reducing local and systemic allergic outcomes such as IL-4<\/a> and IgE (R<\/a>).<\/p>\n

Oral treatment of newborn pigs with L. lactis<\/em> significantly reduced the subsequent frequency of allergy, by dampening the Th-2 immune response (R<\/a>).<\/p>\n

<\/a>4) IBD<\/h4>\n

Soy milk fermented with L. lactis<\/em> exhibited anti-inflammatory effects and prevents IBD in mice (R<\/a>, R<\/a>).<\/p>\n

Administration of heat-killed L. lactis<\/em> suppressed IBD symptoms, such as shortening of colon length, damage to the colon mucosa, and spleen enlargement in mice (R<\/a>).<\/p>\n

It reduced inflammatory cytokine production and nitric oxide expression in mice with colitis<\/a> (R<\/a>).<\/p>\n

<\/a>5) Heart Health<\/h4>\n

L. lactis<\/em> reduced blood pressure, LDL cholesterol<\/a>, and triglyceride contents in hypertensive rats (R<\/a>).<\/p>\n

Milk fermented by L. lactis<\/em> exhibited systolic and diastolic blood pressure- and heart-rate-lowering effect in rats with hypertension (R<\/a>).<\/p>\n

<\/a>6) Aging<\/h4>\n

Long-term oral intake of L. lactis<\/em> suppressed the reduction of bone density and body weight in senescence-accelerated mice, a model of aging (R<\/a>).<\/p>\n

<\/a>Age-Related Hearing Loss<\/h5>\n

Intake of heat-killed L. lactis<\/em> altered the intestinal flora, affected plasma metabolite levels, including fatty acid levels, and slowed down age-related hearing loss in mice, by inhibiting the loss of neurons and hair cells in mouse inner ear (R<\/a>).<\/p>\n

<\/a>Cancer Research<\/strong><\/span><\/h3>\n

L. lactis<\/em> inhibited the proliferation of lung cancer cells, colorectal cancer cells, gastric carcinoma cells and breast cancer cells (R<\/a>).<\/p>\n

The cytoplasmic fraction of L. lactis<\/em> inhibited human stomach cancer cell proliferation and induces cancer cell death (R<\/a>).<\/p>\n

These cell studies may not be relevant at all for cancer treatment in animals or humans.<\/p>\n

<\/a>Mechanisms<\/strong><\/span><\/h3>\n

In cells and animals, researchers have observed that L. lactis<\/em>:<\/p>\n