Can Probiotics Aid in Weight Loss?

What are probiotics? 

Probiotics are a combination of live bacteria and/or yeasts that naturally live in your body.  Fermented foods in particular such as yogurt, sauerkraut, kefir, tempeh, natto, and kombucha all contain naturally occurring probiotics.  However, you can also take a probiotic supplement containing contain large doses of live bacteria, typically Lactobacilli and Bifidobacteria. 

Bacteria is usually viewed in a negative light, so why would we think to take a supplement that is made of bacteria?  Our bodies constantly have both good and bacteria!  When you get an infection, there’s more bad bacteria floating around which knocks your system out of balance.  Good bacteria help eliminate the bad, returning our bodies back to a balanced state.  This balancing act naturally happens in your body.  You don’t actually need to take probiotic supplements to make it happen!  Good bacteria are a natural part of your body and by eating a well-balanced diet rich in fiber helps keep the number of good bacteria at proper levels.

Probiotics are linked to a wide variety of health benefits, including improved gut health, enhanced immune function, and controlling inflammation.  Probiotics are a part of a larger picture concerning bacteria in your body – our microbiome.  Your microbiome is unique to you, which is pretty cool; even twins have different microbiomes!  It is a diverse community of organisms called microbes that work together to keep your body healthy.  Some microbes are considered probiotics where they live in the gut, mouth, urinary tract, skin, and lungs.  Certain types of probiotics help the body digest food, keep bad bacteria from getting out of control, and breakdown and absorb medications.  Some studies have suggested that taking a probiotic supplement may aid in weight loss. 

We pose the question: can probiotic supplements actually help individuals lose weight?

Let’s dive in a bit deeper!

Truthfully, we are unsure of the relationship between probiotic supplements and weight loss.  But through research here is what has been discovered so far.

The use of probiotics modulates the intestinal microbiota by increasing the number of Bifidobacterium spp. and lactic acid sticks responsible for producing SCFA.  SCFA (short chain fatty acids) are an important part of your colon health.  They are produced where the friendly gut bacteria ferment fiber in your colon and are the source of energy for the cells lining your colon.  Probiotics influence appetite and energy homeostasis through increased SCFA production.  It has been shown that some Bifidobacterium spp. and Lactobacillus spp. Produce conjugated linoleic acid (CLA). CLA affects body weight by improving energy metabolism and lipolysis (breakdown of fats to mobilize stored energy during fasting or exercise). 

Influence of probiotics on body weight was best studied in adults.  A study including 87 participants with a body mass index (BMI) 24.2-30.7 kg/m² and abdominal visceral fat area of 81.2 and 178.5cm² were randomly assigned to receiver either fermented milk (FM) containing Lactobacillus gasseri. or FM without the added probiotic.  The participants were asked to consume 200g/day for 12 weeks.  After 12 weeks, there was a significant reduction in BMI, waist and hip circumference, and body fat mass in the participants who consumed the FM with the probiotic.  Conversely, a meta-analysis of nine studies showed that probiotics do not have any effects on weight loss and obesity.

Disorders in the intestinal microbiome cause the development of inflammation, which leads to metabolic disorders such as obesity or diabetes.  Although research is ongoing, a recent discovery of our microbiome having an influence on the energy productions from nutrients, has allowed researchers to develop a new concept of fighting obesity. 

Obesity leads to the development of metabolic diseases such as type 2 diabetes, insulin resistance or non-alcoholic fatty liver disease.  Influence of probiotic supplementation on insulin resistance, lipid profile, glucose level, and markers of the inflammatory state in obese individuals has been tested.  Supplementation with Lactobacillus spp. and Bifidobacterium spp. in adults with non-alcoholic fatty liver disease improved liver function. Patients had a decreased level of alanine aminotransferase and aspartate aminotransferase (indications of liver damage), an increase in GLP-1 (a hormone that induces satiety) and decrease liver steatosis.  The improvement in liver function was accompanied by a reduction in BMI.

Bottom line?

Before probiotics can be used to treat obesity and other metabolic diseases, more research needs to be done.  We also need to determine which groups of bacteria are involved in the etiology of obesity.  Some studies suggest certain strains have a positive effect while in other studies the opposite results were obtained.

There is an array of factors that could throw off our microbiome such as a diet low in nutrient dense foods, stress, and use of certain drugs like antibiotics.  It is important to have a well-balanced diet not only to keep our microbiomes balanced and in check but to keep ourselves healthy! Probiotics will especially be of great benefit to our microbiome health and overall health.