New Study: Good Gut Microbes Could Help With Weight Loss

There are millions of gut microbes that live within every human being, and they all have a role to play in our overall health and wellness.

A recent study ( 1 ) showed that good gut bacteria could aid weight loss in individuals carrying excess weight and those who are statistically overweight (as denoted through a BMI analysis).

We know that certain factors influence our ability to lose weight, such as genetics, which cannot be modified. However, through research on gut bacteria, we now discover a significant new field for medical advancements in weight loss.

These advancements could include procedures called fecal microbiota transplantation ( 2 ) which could potentially replace the good bacteria into an individual who does not have it naturally from someone who does.

Along with the recent findings that show that having good gut bacteria may help weight loss overall, another bank of research ( 3 ) shows that the composition of the good versus harmful bacteria in our gut can influence whether we are “lean or obese.”

What Are Gut Microbiota?

Gut Microbiota

Gut microbiota is present in the digestive tracts of all of us. The community of gut microbiota facilitates the fermentation of dietary fibers, which is especially useful to metabolize and process them correctly.

The American Society for Microbiology ( 4 ) study led by Dr. Diener and his team concluded that “The gut microbiome is a major player in modulating whether a weight loss intervention will have success or not. The factors that dictate obesity versus nonobesity are not the same factors that dictate whether you will lose weight on a lifestyle intervention.”

What Did the Study Uncover?

In the year-long study that included the in-depth analysis of 105 overweight participants, scientists compared the statistics of the gut microbes of the people who lost at least 1% of their body weight per month against those participants that had little to no weight reduction at all.

The results were striking.

When the findings were collected and analyzed, the overweight study participants who had lost 1% or more of their initial baseline weight per month had more “good” bacteria present in the gut.

The good gut bacteria assist in breaking down dietary compounds, such as fiber and complex carbohydrates into more simple sugars, making them easier to digest by the body. The good bacteria thereby facilitate efficient digestion.

There was a particular focus on the bacteria called Prevotella ( 5 ), which may help produce short-chain fatty acids, which are healthy substances created in the body that may reduce inflammation. By reducing the amount of inflammation within the body, we may also benefit from commencing and sustaining weight loss.

Essential Elements to Note About the Study

It is important to note that all participants had their baseline information collected at the beginning of the study, with particular attention paid to cholesterol levels.

It is also important to note that no physical diet requirements were implemented to any participant in the study; they were offered dietary and lifestyle advice and coaching by a professional, but no diet was enforced.

The comparison to draw the study’s conclusions was taken from the persons who lost weight versus those who did not. The participants who lost the prescribed percentage of weight had a predominantly higher proportion of good gut microbes, contributing to their weight loss success.


Recent studies have shown that the balance of microbes within the intestinal tracts of the human body can influence a person’s weight and the further ability to lose weight.

The findings guide towards “good bacteria” present in the gut (gut microbes) being a key indicator in successful weight loss. Medical advancements are being made to prove this and develop interventions for implementation in overweight individuals.

The study shows that the participants who lost weight had a higher proportion of “good bacteria” in the gut than those who didn’t and consequently lost little to no weight.

It is possible that adjusting your diet to include good bacteria can assist in your weight loss goals. It is entirely possible to change your way of eating to encompass a diet that facilitates good bacteria growth, which may improve metabolization and digestion.

Finally, good bacteria in the gut may reduce inflammation instances, contributing to weight fluctuations.

  1. Science Daily (2021) Gut microbiota influences the ability to lose weight.
  2. Fecal Microbiota Transplant Foundation. What is FMT?
  3. Diener C, Qin S, Zhou Y, Patwardhan S, Tang L, Lovejoy JC, Magis AT, Price ND, Hood L, Gibbons SM. Baseline Gut Metagenomic Functional Gene Signature Associated with Variable Weight Loss Responses following a Healthy Lifestyle Intervention in Humans. mSystems. 2021 Oct 26;6(5):e0096421. doi: 10.1128/mSystems.00964-21. Epub 2021 Sep 14. PMID: 34519531; PMCID: PMC8547453.
  4. American Society for Microbiology ASM.
  5. JN The Journal of Nutrition. JN The Journal of Nutrition.