Alterations in the way the gut metabolizes the fatty acid butyrate have been associated with inflammatory bowel disease. A recent genetic analysis suggests that reduced intestinal synthesis of butyrate may be the result of a low fiber diet. Study highlights include:

• Investigators measured the butyryl-CoA:acetate CoA transferase (BCoAT) genes in the stool of healthy persons, and in patients with Crohn’s disease and ulcerative colitis using polymerase chain reaction.
• Disease activity for Crohn’s and colitis were measured by means of fecal calprotectin concentration and clinical evaluation.
• A drop in the ability to synthesize butyrate was found in patients with both active and inactive Crohn’s disease but only in active ulcerative colitis.
• The reduced butyrate synthesizing enzyme levels—as indicated by the lower gene content—was associated with increased inflammation, stenotic behavior, lower microbial diversity, and other abnormalities.
• Reduced BCoAT gene levels were also associated with a diet lower in fiber.