Eating a high-protein diet can significantly alter gut flora and overall body composition, said scientists at the recently concluded ASM Microbe 2024 symposium, which focused on the health effects of partially digested protein in the colon.

Researchers led by Samson Adejumo of the University of Illinois at Chicago discovered that mice given a high-protein diet shed a lot of pounds, reduced their body fat percentage, and experienced a rapid shift in the gut flora. To determine the effects of amino acids on gut flora, the researchers examined a variety of protein-rich diets.

"These results are very important for understanding how protein diets affect the gut microbiome and open the door for more research into the role of diet in promoting a healthy gut and overall health," said lead author Adejumo.

As part of their investigation, the researchers conducted a four-week study on sixteen mice. They fed the mice a regular diet for two weeks. For the next two weeks, they changed their diet to include more protein and aromatic or branched-chain amino acids. They took body measurements once a week and faeces samples every day to monitor changes. In order to learn more about the many bacteria that live in the stomach, researchers have turned to DNA sequencing.

Gut flora were found to be significantly affected by the type of protein consumed. When compared to mice given standard or branched-chain amino acids, those given aromatic amino acids lost a greater amount of weight and fat.

Researchers achieved a 97% success rate in using machine learning to forecast dietary changes dependent on gut bacteria. There is a clear correlation between dietary changes and microbial shifts, as shown below. 

These results provide more evidence that specific proteins may have distinct effects on gut health and body composition.

This study, which investigates the effects of diet on gut flora and general health, was supported by the UIC Hampton-Marcell lab startup grant. 

To fully understand the implications for human health, however, additional research is needed, according to the researchers.