Study: Ketogenic diet has potential to treat irritable bowel syndrome

Ms. Murphy noted that if it weren’t for the chronic disease epidemic driven by excessive intake of high-refined carbohydrates, sugars, and highly refined seeds and vegetable oils, people might not need to explore therapeutic diets.

Treatment options for bowel disorders

While the authors did not specifically evaluate studies on the effects of diet on gut barrier function, the human microbiome review article sheds light on how the ketogenic diet may be a “treatment option for patients with certain gastrointestinal disorders.”

The authors note several specific findings:

• The ketogenic diet increases β-hydroxybutyrate, which may limit the growth of certain beneficial gut bacteria, but has also been shown to enhance intestinal function, reduce intestinal barrier permeability, and have therapeutic effects in ulcerative colitis, a form of inflammatory bowel disease (IBD).

• Ketosis reduces Th17 cells in the small intestine, which are responsible for maintaining the intestinal barrier and clearing pathogenic microorganisms, but are also associated with inflammatory and autoimmune diseases.

• Ketosis may help support the mucus layer in the intestines.

• A diverse plant-based diet produces the short-chain fatty acid butyrate, whereas in a high-fat diet, butyrate is not produced and is replaced by other molecules.

Butyrate is important because it helps maintain the barrier function of the intestine, protecting the body from invading toxins and immune responses that can lead to various autoimmune diseases. Since the ketogenic diet is low in fiber and plant matter, there is less fermentation in the colon, a process that produces butyrate.

According to the review, there are at least four molecules that can replace butyrate, and it mentions that a study published in Nature in 2014 showed that people on a ketogenic diet had increased levels of a molecule called isobutyric acid. Although its concentration is lower, the authors of the review believe that isobutyric acid seems to be more effective and can affect mucus secretion, have antimicrobial activity and immune regulation.

“Research is needed to clarify whether increases in β-hydroxybutyrate, reductions in inflammation, changes in insulin and glucose metabolism, reductions in caloric intake, improvements in the gut microbiome, or other unidentified factors result directly from low-carbohydrate or ketogenic diets,” the authors wrote.