A new study by University of Pittsburgh researchers suggests that intestinal microbes may trigger foraging behaviors for foods containing certain nutrients.
In the study, researchers saw that mice bred to have no microbiome but later colonized with the gut microbiomes of different animals showed significant variations in their dietary behaviors.
The authors believe that gut bacteria could affect our food choices and cravings by influencing the availability of essential amino acids.
The decisions we make about what to eat might not just come from our brains. The mechanisms driving our dietary choices may reach back to evolutionary processes with gut microbes.
For decades, scientists have wondered if intestinal flora drives food urges. However, no one had ever directly tested the hypothesis on animals larger than a fruit flyTrusted Source.
Dr, Kevin Kohl and Dr. Brian Trevelline from the University of Pittsburgh, Pennsylvania explored this possibility with germ-free mice.
Dr. Kohl is an assistant professor in the Department of Biology at the Kenneth P. Dietrich School of Arts and Sciences at the University of Pittsburgh. Dr. Trevelline is now a Rose postdoctoral fellow at the Cornell Lab of Ornithology.
Their research showed that the mice that received diverse types of microbiota voluntarily changed their diet preferences.
“Our work shows that animals with different compositions of gut microbes choose different kinds of diets,” Dr. Kohl said.
This research appears in the journal Proceedings of the National Academy of Sciences.
Microbes and amino acids In an interview with Medical News Today, Dr. Trevelline explained how microbes play a role in nutrient making.
“Animals need a suite of essential amino acids to survive. But the microbes that live inside of our guts need [to] grow and have some of these same nutrients or make nutrients that the human body or the animal body can recognize. For instance, they make these essential amino acids, and then they’re released into the gut where they can be absorbed by the host,” he said. Dr. Kohl, meanwhile, suggested that the microbes might also be broken down and digested to release nutrients as well.
Dr. Trevelline said the microbes in the gut were beneficial contributors to a lot of processes, particularly by synthesizing the nutrients humans need and supplementing our diets.