- The composition of the gut microbiome is increasingly recognized as essential to overall health and effective weight management.
- A new study in mice suggests that high-protein diets may influence gut bacteria and their byproducts, potentially affecting weight and body composition.
- More research is needed, but the findings suggest that a personalized diet based on an individual’s gut microbiome could promote better health outcomes in the future.
The gut microbiome is a complex community of microorganisms found in our digestive system that affects almost every aspect of our health, from digestion and immune function to metabolic processes and body weight.
Since diet plays an important role in the composition and diversity of gut microorganisms, it has become increasingly important to understand the impact of our food choices on our gut ecosystem.
Western cultures are increasingly adopting high-protein diets, potentially driven by a growing body of research supporting high-protein diets for
This trend led researchers at the University of Illinois at Chicago to investigate the impact of protein diets on gut microbiome diversity and body composition in a recent study in mice.
The study abstract was presented at ASM Microbe 2024, the annual meeting of the American Society for Microbiology, on June 15, 2024 in Atlanta, Georgia.
The study also explored how proteins fermented by gut bacteria in the colon can produce beneficial metabolites, such as
They found that switching from a carbohydrate diet to various high-protein diets in mice resulted in significant weight loss, reduced body fat, and rapid changes in the composition of the gut microbiome.
Samson Adejumo, a doctoral student in biology at the University of Illinois at Chicago, led the research. He said Medical news today that this study has not yet been peer-reviewed, but that the authors are preparing its publication.
He added that this could appear in the Nutrition Diary Or Nutrient Reviews in the future.
This short-term experimental study lasted four weeks and included 16 mice.
For the first two weeks, the mice received a regular carbohydrate diet. The researchers then transferred the mice to four separate protein diet groups for the remainder of the study:
- standard protein diet
- 10% aromatic amino acid
- 10% Branched Chain Amino Acid Diet
- Diet 5% aromatic amino acids and 5% branched chain amino acids
The volume of each diet was the same and contained an equal amount of protein.
The researchers collected fecal samples daily and took weekly body composition measurements to monitor changes in body fat and muscle mass.
They extracted DNA from the fecal samples and analyzed it to observe how the mice’s gut bacteria changed throughout the study.
The study found that the gut microbiota responded differently to each type of diet, showing significant changes between the carbohydrate diet and the four different protein diets.
Using machine learning, the researchers were able to predict with 97% accuracy what protein diet the mice ate simply by observing their gut bacteria.
For MNTAdejumo explained which protein diets specifically led to the greatest reductions in fat mass and body weight.
“A combination of 5% branched-chain amino acids with 5% aromatic amino acids resulted in the lowest body weight, while (a 10% aromatic amino acid diet) had the lowest body fat percentage lowest but highest weight increase,” he said.
“These results imply that beyond the type of diet, the type of gut microbiome that metabolizes the diet is much more important. Dietary gut microbiome metabolism has the greatest impact on host body composition.
— Samson Adejumo, principal investigator
“The result for weight (and) body composition is unexpected because branched-chain amino acids are involved in building muscle proteins and we expect that an increase in intake (of branched-chain amino acids ) increases lean mass and not fat mass.” he said.
Further research is needed to confirm whether protein diets caused all the observed changes in body composition and gut bacteria in mice.
However, the predictable patterns identified by the researchers suggest a link between protein diets and changes in the gut microbiome.
Adejumo explained how changes observed in the gut microbiota may be linked to body composition and weight loss.
He said
“In contrast, branched-chain amino acids are involved in the maintenance of muscle function and protein production in muscle development.”
He further explained:
“Changes in the gut microbiome reflect the bioavailability of essential gut microbiome ingredients. Anytime a gut microbiome can utilize diet ingredients, it will positively affect body composition, particularly fat mass and lean mass.
Essentially, changes in the gut microbiota can be influenced by the types and amounts of proteins consumed, thereby affecting body composition. This also implies that a healthy gut microbiome may be crucial for maintaining optimal body composition and weight.
MNT also spoke with Alyssa Simpson, RDN, CGN, CLT, registered dietitian, certified gastrointestinal nutritionist and owner of Nutrition Resolution in Phoenix, Arizona, who was not involved in the study.
“Changes in the gut microbiota can significantly influence body composition and weight loss by altering the efficiency with which calories are extracted from food,” she said.
She suggested, for example, that a higher ratio of certain bacteria might improve calorie absorption, potentially contributing to weight gain.
Additionally, Simpson noted that “some bacteria produce
Simpson says more research is needed, but diets rich in certain proteins, particularly plant-based proteins, have been shown to improve gut health and body composition in humans.
“Plant-based protein diets promote gut health by supporting beneficial bacteria and bowel regularity. They are generally lower in calories and saturated fat than animal-based diets, which can potentially help with weight management and body fat reduction.
—Alyssa Simpson, RDN, CGN, CLT
Plant-based diets are also rich in dietary fiber, promoting the growth of
Although the body produces them, she also suggests consuming dietary sources of amino acids like glutamine and arginine, which “help maintain a strong intestinal barrier, preventing harmful substances like lipopolysaccharides from entering the bloodstream and potentially influence body composition.
For those looking to improve the gut microbiome, overall health and body composition through diet, Simpson recommends prioritizing “a rich variety of plant-based foods like fruits, vegetables, nuts , seeds, whole grains and legumes.”
She also advises “moderate protein intake to maintain muscular and metabolic health without excess unhealthy fats.”
Most importantly, “select a dietary approach that suits your personal preferences, health goals and lifestyle to achieve lasting results,” Simpson emphasized.
Adejumo said that as a next step, “we plan to do functional analyzes and carry out mechanistic experiments to be able to improve overall health.”
“We also intend to formulate our diets with unique amino acids to fully understand the effect of each amino acid on the diet and identify specific gut microbial strains involved in protein fermentation,” he said. added.
Although more research is needed and animal studies do not translate directly to humans, learning how
“This conception of