Diverticulosis is a condition of the colon with pockets forming on the intestinal wall due to increased pressure, most likely from constipation. Sometimes food collects in these pockets (like bubbles on a tire inner tube when the outer tire is weak), and this can lead to infection and inflammation, a condition called diverticulitis.
For many years, patients with diverticulosis have been told to avoid certain fibrous foods, such as nuts, seeds, and corn, particularly popcorn. However, this was a theoretical concern, as it “seemed logical” that these foods could get trapped in the diverticula and lead to problems. It now turns out that the scientific data does not support these restrictions (most fibrous
foods are not irritating, and indeed can help move things through the bowel and reduce constipation).
Researchers followed 47,228 men over 18 years and compared those with high nut, seed, corn, and popcorn consumption with those who consumed the least. (Strate LL, et al., Nut, corn, and popcorn consumption and the incidence of diverticular disease. JAMA. 2008 Aug 27;300(8):907-14.) For the most part they found no association between these foods and diverticular disease. However, contrary to “popular” medical opinion, high intake of nuts and popcorn actually significantly reduced the incidence of diverticulitis, by 20 percent in the case of nuts, and by 28 percent for popcorn. In general, high fiber foods are associated with less diverticulosis, and now it appears
that they can help prevent the inflammatory consequences that sometimes occur.