Gut Problems? Eat Walnuts, Turkey

If you don't feel well in your gut, you don't feel well, period. Your gastrointestinal tract is a high-wire balancing act at the best of times. But when you suffer from irritable bowel syndrome, or your intestinal flora are unbalanced, consider your apple cart officially upset.

But new research has found us ways to settle our stomachs, and the cures can likely already be found in our kitchen. One of these is our old friend, walnuts.

“Walnuts have been called a ‘superfood’ because they are rich in the omega-3 fatty acid, alpha-linolenic acid and fiber, and they contain one of the highest concentrations of antioxidants,” said Lauri Byerley, PhD, RD, Research Associate Professor of Physiology at LSU Health New Orleans School of Medicine. “Now, an additional superfood benefit of walnuts may be their beneficial changes to the gut microbiota.”

Byerley and her team added walnuts to the diet of one group of rodents, and fed another group no walnuts. They then measured the types and numbers of gut bacteria in the descending colon and compared the results. In the walnut-eating group, the numbers and types of bacteria changed, yielding a significant increase in beneficial bacteria like Lactobacillus.

“We found that walnuts in the diet increased the diversity of bacteria in the gut, and other non-related studies have associated less bacterial diversity with obesity and other diseases like inflammatory bowel disease,” said Byerley. “Walnuts increased several bacteria, like Lactobacillus, typically associated with probiotics suggesting walnuts may act as a prebiotic.” The research was published in The Journal of Nutritional Biochemistry.

Not to be confused with its “irritable” cousin, inflammatory bowel disease can be triggered when harmful microbes hidden in the food we eat insinuate themselves into our bodies. This inflammation can be lessened and even counteracted by cells that promote tolerance and, protect the body.

Scientists at Washington University School of Medicine in St. Louis have just discovered that tryptophan – that compound found in turkey that's famous for putting us to sleep on Thanksgiving – triggers the appearance of the “tolerance promoting” cells in the guts of rodents.

“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 study’s senior author. “The more tryptophan the mice had in their diet, the more of these immune cells they had.”

If the team's findings hold true in human studies, it will be great news for the more than a million Americans suffering from inflammatory bowel disease. The team's research was published in the journal Science.