Can Probiotics Help Support A Healthy Weight? Here's The Science*

Your gut is a teeming warehouse of trillions of bacteria—some of those are good and protective while others are not. When everything is functioning optimally, your body is able to maintain a healthy balance. But it doesn't take much to throw it out of whack.

When the bacteria in the intestinal tract (i.e., your gut microbiota) lack in volume or diversity, or the wrong types of microorganisms start to flourish, it not only can affect your health, but it can also make healthy weight maintenance more difficult.

Why? Because your gut bacteria are intricately connected with not only your digestive system, but also your metabolism and whole-body health.*

A probiotic supplement that contains science-backed strains of good bacteria can help maintain or restore a healthy microbial balance to your digestive system.*

Research has shown that the bacterial makeup in individuals with obesity1 is less diverse than in individuals who are lean.

But it presents a chicken-or-the-egg question—does the microbial imbalance cause weight gain or does the extra weight somehow change the balance of bacteria?

Renowned integrative physician Robert Rountree, M.D., thinks the evidence is clear, "There is no question that the bacteria in our gut can affect our weight."* He first cites animal studies, in which obese mice are given a fecal transplant2 from lean mice and, consequently, lose weight and body fat.*

This might be due to how gut bacteria interact with our cells and digestive process.

One study found that simply overeating can tip the balance in favor of bad bacteria3. The problem? As Rountree explains it, "Certain bacteria are better at extracting energy from food than others."

This means these bacteria can harvest even more calories4 from the increased intake of food, to be turned into energy and body fat.* A double weight-gain whammy, if you will.

In addition, gut bacteria play a role in appetite regulation and satiety (the feeling you get after eating a huge, delicious meal).*

When the "good" bacteria outnumber the "bad," the levels of short-chain fatty acids increase in the gut, triggering the production of hormones5 that regulate appetite.* So, if these hormones are out of balance, then you might not get the signal that you are full.

Although researchers identify these strains with a combination of unique letters and numbers, not all supplement labels actually list the strains of bacteria they contain—sometimes you'll find only the genus and species—such as Lactobacillus rhamnosus or Bifidobacterium lactis. 

In contrast, mbg's director of scientific affairs Ashley Jordan Ferira, Ph.D., R.D.N. explains that, "high-quality and transparent supplement brands will absolutely identify the probiotic at the strain level (genus, species, and strain). Look for those three pieces of info, because that's how probiotics are clinically researched, by strain."

Exciting research continues to emerge for this specific area of probiotic evidence.

Although more research is needed to understand the complex interactions between the gut microbiome and weight maintenance, Rountree says, "I think we are on the verge of discovering what bacteria might be causing this obesity problem," and recent clinical studies in the past five to 10 years are zeroing in on the possible benefits of probiotic supplements to aid in a healthy weight.* 

In a study of 125 men and women with obesity, published in the British Journal of Nutrition, it was found that probiotic supplementation helped women lose weight and maintain their weight loss11 over a 24-week period while following a reduced-calorie diet.*

The women taking the probiotic supplement lost significantly more weight than women in the control group, who also followed a reduced-calorie diet but did not take the probiotic supplement.* 

Another study, this one of 90 adults with overweight and obesity, found that taking a probiotic supplement for 12 weeks had a favorable effect on participants' visceral fat12—the fat that accumulates near the liver, stomach, and intestines and increases the risk for many diseases.* 

These and other studies have used individual strains and combinations of probiotic bacteria, with beneficial outcomes for weight maintenance.*

If you take a probiotic supplement, then it can offer a weight-maintenance advantage, but that alone won't be enough to knock off the extra pounds.*

The research on probiotics and weight is cutting edge and promising. Scientists have already identified several strains that can support healthy weight.*