Diverticulosis and diverticulitis: 6 myths vs. facts

The colonoscopy report says diverticulosis, and suddenly everyone has advice: skip the seeds, never eat popcorn again, expect a painful flare sooner or later. Much of that advice was passed along long before there was good research to test it.

Diverticulosis means small pouches have formed in the wall of the colon. Diverticulitis is when that area becomes inflamed, which can be painful and occasionally serious. Here are six common myths about both, and what the evidence actually shows.

Myth 1: Diverticulosis means diverticulitis is coming

Fact: most people with diverticulosis never develop diverticulitis. In a study of 2,222 patients whose diverticulosis was found during colonoscopy in a Veterans Affairs health system, 4.3% developed diverticulitis over an 11-year follow-up. Using a stricter definition confirmed by imaging or surgery, the figure was about 1% (Shahedi et al., 2013).

Younger patients had a higher risk: each additional decade of age at diagnosis lowered the risk by 24% (Shahedi et al., 2013). If you're in your 40s, that's a reason to pay attention to prevention, not a reason to panic.

Myth 2: You have to avoid nuts, seeds and popcorn

Fact: the research doesn't support this long-standing rule. A study followed 47,228 men for 18 years. Those who ate popcorn at least twice a week had a lower risk of diverticulitis than those who ate it less than once a month, with a hazard ratio of 0.72, and nuts showed a similar trend. Nut, corn and popcorn intake wasn't linked to diverticular bleeding or to uncomplicated diverticulosis either (Strate et al., 2008).

The study included only men, so it isn't a perfect match for women. But the authors concluded that the recommendation to avoid these foods should be reconsidered.

Myth 3: Diet doesn't make a difference

Fact: overall eating patterns seem to matter. In a cohort of 46,295 men, those whose diets most closely matched a Western pattern, high in red meat, refined grains and high-fat dairy, had a 55% higher risk of diverticulitis than those with the lowest scores. A prudent pattern, high in fruits, vegetables and whole grains, was linked to a 26% lower risk. The difference was mostly explained by fiber and red meat intake (Strate et al., 2017).

This was an observational study, again in men. Still, it fits the practical advice from the American Gastroenterological Association for lowering the risk of recurrence: eat a high-quality diet, maintain a healthy weight, stay physically active and don't smoke. The AGA also advises avoiding nonsteroidal anti-inflammatory drugs, such as ibuprofen, except aspirin prescribed to prevent heart problems, and notes that genetics play a role too (Peery et al., 2021).

Myth 4: Diverticulitis always needs antibiotics

Fact: not every mild case does. The AGA advises that antibiotics can be used selectively, rather than routinely, in people with a healthy immune system who have mild, uncomplicated diverticulitis. For people who are immunocompromised, antibiotics are strongly advised (Peery et al., 2021).

The American College of Physicians similarly suggests managing most uncomplicated cases outside the hospital and initially treating select patients without antibiotics. It suggests a CT scan when the diagnosis is uncertain (Qaseem et al., 2022). This is a decision for your clinician, who will weigh your symptoms, test results and overall health.

Myth 5: After a few flares, you need surgery

Fact: the number of episodes alone shouldn't decide it. The AGA advises against recommending elective surgery based on how many episodes someone has had. Instead, the discussion should be personalized, weighing disease severity, the patient's preferences and values, and the risks and benefits (Peery et al., 2021).

The AGA also notes that the risk of complicated diverticulitis is highest with the first episode (Peery et al., 2021). That can be reassuring if you've already been through one and recovered well.

Myth 6: Once you've had diverticulitis, colonoscopy doesn't matter

Fact: follow-up can still be important. Rarely, a colon cancer is misdiagnosed as diverticulitis. According to the AGA, whether you need a colonoscopy after an episode depends on your history, your most recent colonoscopy and how severe the episode was. If you have ongoing symptoms after diverticulitis, other diagnoses should be ruled out with both imaging and a colonoscopy (Peery et al., 2021).

When to get care

Call your doctor or seek urgent care if you have:

• Abdominal pain that is severe, persistent or getting worse, often in the lower left side
• Fever or chills along with abdominal pain
• Nausea or vomiting that keeps you from drinking fluids
• Blood in your stool or bleeding from the rectum
• Symptoms that don't improve, or that come back after treatment

Sources

1. Shahedi K, Fuller G, Bolus R, et al. Long-term risk of acute diverticulitis among patients with incidental diverticulosis found during colonoscopy. Clin Gastroenterol Hepatol. 2013;11(12):1609-13. PMID 23856358
2. Strate LL, Liu YL, Syngal S, Aldoori WH, Giovannucci EL. Nut, corn, and popcorn consumption and the incidence of diverticular disease. JAMA. 2008;300(8):907-14. PMID 18728264
3. Strate LL, Keeley BR, Cao Y, Wu K, Giovannucci EL, Chan AT. Western dietary pattern increases, and prudent dietary pattern decreases, risk of incident diverticulitis in a prospective cohort study. Gastroenterology. 2017;152(5):1023-1030.e2. PMID 28065788
4. Peery AF, Shaukat A, Strate LL. AGA clinical practice update on medical management of colonic diverticulitis: expert review. Gastroenterology. 2021;160(3):906-911.e1. PMID 33279517
5. Qaseem A, Etxeandia-Ikobaltzeta I, Lin JS, et al. Diagnosis and management of acute left-sided colonic diverticulitis: a clinical guideline from the American College of Physicians. Ann Intern Med. 2022;175(3):399-415. PMID 35038273

This article is for general information and isn't medical advice. If you have symptoms of diverticulitis, contact your healthcare provider for diagnosis and treatment.