Diverticula are sacs formed by a fold of the lining of the intestinal wall. They project from within the bowel through the muscle surrounding the bowel, and may occasionally trap feces moving through the intestine. Diverticula are extremely common and usually harmless. They often appear in bunches. Each is typically less than an inch in diameter. They tend to appear after age 40 and are more likely to appear in seniors.
Diverticulosis is the condition of having one or more diverticula. Usually there are no symptoms or problems associated with this condition, yet it is present in 75% of people over 80 years old.
Occasionally, diverticula become inflamed. If you have one or more inflamed diverticula, you are diagnosed with diverticulitis. The word ending "-itis" means inflammation. Diverticulitis can be a serious condition.
Diverticula can also appear in the gastrointestinal tract above the stomach, in the esophagus. In these cases, it's food rather than feces that may get trapped. Esophageal diverticula don't cause dangerous problems, but a few people find that trapped food comes back up when they bend over or lie down.