Diverticulitis is the inflammation of the chronic disease diverticulosis, or in layman’s terms, bulging pockets. The bulging pockets most often occur in the colon, but they can occur anywhere along the digestive tract and are caused by weakness of the muscle wall. Basically, it’s a flare-up you can get when you have the condition, and it seems to be more common now than ever.
Hospital admissions for the issue have increased more than 25% in recent years, according to a study published in The Journal of the American Medical Association.
Be aware that sometimes you might not even know you have diverticulitis.
“The majority of people who have diverticulosis are asymptomatic and about 25% of them may develop alternating diarrhea and constipation, abdominal pain, and poor motility,” says Jonathan Valdez, RDN, owner of Genki Nutrition.
When Valdez meets with patients who are potentially suffering from diverticulitis, he says his first question is always “Is there inflammation or pain?” If so, he prescribes a low-fiber diet and recommends removing certain foods to discover food intolerances. There are some superfoods that can help prevent more pockets from forming, while other foods can irritate your stomach further. (While you can still enjoy some of these items once in a while, it's best to avoid them during a flare-up.)
With Valdez’s expert help, we rounded up the ultimate diverticulitis diet to alleviate symptoms and keep your digestive system on track. Here’s what to eat (and what to avoid).
What to Eat
Oatmeal With Soy Milk
One cup of oatmeal contains about four grams of fiber and six grams of protein. When you add about one cup of soy milk, you add an additional eight grams worth of protein. “When you’re sick, your immune system needs protein to help fight possible infections,” Valdez says. Soy milk is preferred to cow’s milk because it is often more tolerable if your infection lies in the small intestine.
Fruit Without Skin
Opt for fruit like apples, peaches, and pears since they’re low in fiber (just make sure to remove the skin before eating). Low-fiber foods help give your digestive system the break it needs during an infection. You can also have a lot of watermelon, grapes, cantaloupe, and honeydew since they all contain less than 2.5 grams of fiber per cup. “This will help you stay under the 10 to 15 grams of fiber per day limit, but you’ll still be able to meet your servings of fruit and vegetables,” says Valdez.
Don’t forget about protein in the form of fish, chicken, eggs, and beef. These foods are key because they’re all low in fiber, but they’re high in protein. According to Valdez, protein helps you preserve muscle while you’re fighting off the infection.
What to Avoid
As mentioned, if your diverticulitis lies in your small intestine instead of your colon, dairy may cause a problem for you. When you have a flare-up, it can make it more difficult for you to digest lactose (a sugar found in cow's milk) because of a temporary lack of lactase (an enzyme found in the lining of the small intestine).
Alternative: Soy milk or other nut-based milk
Foods With Raffinose
Raffinose is a sugar digested in the large intestines by bacteria (it results in gas). If someone is already bloated (which happens when you have diverticulitis), it can aggravate the symptoms. Foods to avoid include broccoli, kale, cabbage, beans, turnips, arugula, cauliflower, bell peppers, sweet potatoes, and Brussels sprouts.
Alternative: Zucchini, romaine lettuce, iceberg lettuce, okra, green beans, and spinach
When your stomach is already irritated, you’re trying to avoid bloating further (see above). The carbonation found in soda can increase your bloat.
Alternative: Warm ginger tea or water
Godman H. Study Says Aggressive Treatment for Diverticulitis is Often Overused. Harvard Health Publishing, Harvard Medical School. January 15, 2015.
Swanson SM, Strate LL. Acute Colonic Diverticulitis [published correction appears in Ann Intern Med. 2020 May 5;172(9):640]. Ann Intern Med. 2018;168(9):ITC65-ITC80. doi:10.7326/AITC201805010