Open a PDF version to print this topic

HealthInfo Waitaha Canterbury

Eating guidelines for diverticulosis, diverticular disease & diverticulitis

Ngā aratakinga mō te māuiuitanga, ngā pokenga, me ngā whakawaikura ki te terotero

Diverticula are small pouches or bulges that form in the wall of your large bowel (your colon or large intestine). Diverticula do not always cause symptoms or problems. If you have them without any symptoms, it's called diverticulosis. It's a common condition among older people, affecting around 80% of people over 80.

If you have diverticulosis with symptoms like cramps or bloating with diarrhoea or constipation, it's called diverticular disease.

Diverticulitis is when the diverticulum become inflamed or infected. This can cause symptoms such as lower tummy (abdominal) pain or bloating.

Eating guidelines for diverticulosis and diverticular disease

Most people with diverticulosis and diverticular disease should follow a high-fibre diet. This can help to keep your poo soft and easy to pass and reduce the pressure in your large bowel. It can also help to ease symptoms you may already have, such as bloating, constipation, diarrhoea (the runs) and pain.

High-fibre foods include vegetables, fruit, nuts, seeds, legumes (cooked dried beans, split peas and lentils), brown rice, wholegrain breads and cereals.

If your diet is low in fibre, it's important that you gradually add more fibre over the course of a few weeks. This will help to prevent side effects, such as bloating and wind (flatulence), which sometimes happen with a high-fibre diet.

Fibre and fluid for healthy bowels explains more about eating a high-fibre diet.

Foods to avoid to prevent diverticulitis attacks

In the past, people with diverticula were told to avoid nuts, seeds, popcorn and foods with small seeds, such as tomatoes, cucumbers and strawberries. We thought these foods could get stuck in diverticula and cause diverticulitis (inflammation). But there is no proof that these foods cause diverticulitis. In fact, eating a high-fibre diet – which may include nuts and seeds – might make it less likely that you will get diverticulitis.

Fibre supplements

If you do not get better with a high-fibre diet, your doctor may suggest you take a fibre supplement (also called bulk-forming laxatives or bulking agents). You can get them from your general practice team on prescription or buy them at the pharmacy. You can also get some at the supermarket. Examples of bulk-forming laxatives include psyllium (Konsyl-D, Metamucil and Mucilax) and wheat dextrin (Benefiber).

Bulk-forming laxatives can have some effect within 12 to 24 hours but may take two to three days to have their full effect. Take them according to the manufacturer's directions or as your general practice team, pharmacist or dietitian tells you.


High-fibre foods and fibre supplements soak up fluid so it's important to drink at least eight cups of fluid each day. Water is best but milk or milky drinks, hot drinks, soup, custard and ice blocks all count as fluids.

Go easy on fruit juice, cordial, and fizzy drinks as they're all high in sugar.

How to get enough to drink explains more about making sure you get enough fluid.

Eating guidelines for diverticulitis

If you have a flare-up of diverticulitis, you may be told to follow a low-fibre diet to help your digestive tract rest and heal. If your symptoms are severe you may need to take medicine and stay in the hospital for a while.

You might need a clear liquid diet for a short period to give your bowel a rest. Suitable fluids include water, apple juice, strained tomato or vegetable juice, Lucozade, lemonade, clear soups (for example, chicken stock in hot water), black tea and coffee. Once your symptoms improve, you can slowly start to eat a low-fibre diet. When you no longer have symptoms, you can return to a normal high-fibre diet.

Written by HealthInfo clinical advisers. Last reviewed July 2022.


See also:

Fibre & fluid for healthy bowels

Reading food labels

Page reference: 147490

Review key: HIDIV-114745