Does the gut microbiome play a role in weight loss? For anyone who has ever attempted a diet, the answer to this question is critical to achieving their goals. Recent medical research suggests that the trillions of bacteria in our gut, aka the microbiome, play a vital role in weight loss.

When it comes to the gut and weight loss, diversity matters. The bacteria in the gut microbiome are responsible for digesting and metabolizing the food that we eat. Which, in turn, impacts our body composition. But how does diversity affect weight loss?

Studies have shown that leaner people have a more diverse collection of bacteria living in their gut as compared to people with obesity. The diversity of bacteria are essential because of their function. When these bacteria breakdown food through complex chemical reactions, they determine how much of the energy will be absorbed by the body. When we absorb too much energy, aka calories, we store the excess as fat to be used another day.

The differences in gut bacteria are so crucial that Rob Knight, Ph.D., and co-founder of the American Gut Project, says

we could predict whether one was lean or obese based solely on their gut microbes

Although heredity and genetics play a role in the development of the bacteria in our microbiome, the foods we eat are also important.

Surprisingly mice can teach us a lot about the microbiome and weight loss. A recent study conducted by Johns Hopkins Medical center revealed a link between obesity in mice and the microbiome. This study demonstrated that there was, in fact, a difference between the bacteria found in the intestinal microbiome of lean mice as compared to obese mice. Interestingly, when the lean mice were colonized with the obese mice, the lean mice gained weight. Two types of bacteria, Bacteriodetes and Firmicutes, were responsible for the changes in weight. 

The research into the effects of the microbiome on weight loss is still in its early stages. However, with an improved understanding of our gut microbiome, it may be possible to customize our diets to promote the types of intestinal bacteria which encourage weight loss.