Research from North Carolina State University has revealed that different protein sources in a diet can influence the gut microbiome’s population and function. The study indicates potential implications for preventing and treating gastrointestinal diseases affecting millions worldwide.
Alfredo Blakeley-Ruiz, an NC State postdoctoral researcher and co-corresponding author, stated, “There’s something wrong with what we’re eating today, and we are not close to knowing what that is.” The researchers investigated the effects of various protein sources, such as those found in milk, eggs, and plants like pea or soy, on the gut microbiomes of mice. The study involved mice being fed diets containing a single protein source, including egg whites, brown rice, soy, and yeast, for a week at a time.
Utilizing a combination of metagenomics and metaproteomics with high-resolution mass spectrometry, the researchers observed notable changes in the gut microbiome. “The composition of the gut microbiome significantly changed every time we changed the protein source,” reported Blakeley-Ruiz. “The protein sources with the biggest functional effects were brown rice, yeast, and egg whites.”
Particularly, the study discovered that dietary protein impacts amino acid metabolism, a finding the researchers anticipated, and complex sugar degradation. “Brown rice and egg white diets increased amino acid degradation in the mouse gut microbiome,” Blakeley-Ruiz explained. The study suggested that these dietary changes could have health implications due to their influence on amino acid degradation, which can lead to the formation of toxins and affect the gut-brain axis.
The research further indicated that proteins containing glycans led to shifts in the gut microbiome’s enzyme production. “This could be really meaningful, health wise,” said Blakeley-Ruiz concerning the changes caused by certain diets, especially the egg white diet.
Manuel Kleiner, another NC State co-author, commented that this investigation sets the stage for further studies on dietary protein’s impact on the gut microbiome. Kleiner noted the artificial nature of the diets as a study limitation but emphasized the significant effects observed. “Our study shows not only which bacterial species are in the gut microbiome and their abundance, but also what they are actually doing,” he said.
The research paper, published in The ISME Journal, lists additional NC State co-authors and was supported by grants from the National Institutes of Health and the USDA National Institute of Food and Agriculture.
