Research suggests that eating a high-protein diet could help to ease the symptoms of irritable bowel syndrome.
Experts believe they have found evidence that the combination of one form of gut bacterium and a protein-rich diet contributes to a less inflammatory gut immune system.
Researchers at Washington University School of Medicine discovered a form of tolerance-boosting cell in mice that carried a certain kind of bacterium in their guts.
This bacterium requires tryptophan, which is one of the building blocks contain in proteins, to cause the cells’ appearance.
“We established a link between one bacterial species – Lactobacillus reuteri – that is a normal part of the gut microbiome, and the development of a population of cells that promote tolerance,” said Marco Colonna, MD, the Robert Rock Belliveau MD Professor of Pathology and the study’s senior author.
When the researchers doubled the amount of tryptophan in the mice’s feed, the number of such cells rose by about 50 per cent and when tryptophan levels were halved, the number of cells dropped by half.
“The more tryptophan the mice had in their diet, the more of these immune cells they had.”
If these findings are similar in humans, it would mean that combining L. reuteri and a diet full of tryptophan could lead to better gut health, relieving millions of people of pain.
It is not clear whether this link is present in humans but defects in genes related to tryptophan have been found in people with gut issues.

