What is diverticular disease?

A diverticulum is a bulge through the inner lining of the colon (large bowel) to form a small pouch with a narrow neck. Diverticular disease is when these pouches cause symptoms.

What are the symptoms?

Many people have diverticula pouches in the large bowel with no symptoms and may not even be aware that the pouches are present. This is called diverticulosis. Around 25 per cent of people with diverticulosis may experience symptoms such as feeling bloated and intermittent lower abdominal pain which may be relieved by passing stools (having a poo) or breaking wind.

Diverticulitis occurs when the diverticular pouches become inflamed or infected, which can lead to constant severe abdominal pain, fever, nausea, constipation, diarrhoea and rectal bleeding.

All of these symptoms can be caused by other diseases so it is very important that you discuss them with your doctor.

Who is at risk?

Research has shown that diverticular disease is associated with ageing, genetics and a low fibre diet.
A low fibre diet can cause constipation and straining when passing stools, which is thought to lead to formation of diverticular pouches. It is more common in western countries where the average fibre intake is generally below the minimum recommended level per day.

Treatment

Antibiotics and pain killers can be used to treat diverticular disease. Your doctor will advise you about the best course of treatment.

How can diet affect diverticular disease?

Historically, it was recommended that a ‘low residue’ diet should be followed. This meant avoiding poorly digested foods such as nuts, seeds, popcorn and fruit and vegetable skins, as it was thought that these foods might get stuck in the diverticular pouches and cause them to become inflamed or infected. This is no longer recommended as there is little evidence to support this advice and restricting your diet unnecessarily may lead to nutritional deficiencies.

It is now recommended that you eat a high fibre diet. This can help to ensure that your stools are soft and bulky and keeps bowel movements regular. A high fibre diet can also improve the natural bacteria in the bowel which helps keep the lining of the bowel healthy. Aim to increase the amount of fibre you eat gradually over a few weeks to avoid side effects such as wind and bloating and try to include a high fibre food at every meal.

See the table on the next page for examples of higher fibre foods to include in your diet. If you find you are unable to include higher fibre foods in your diet, a fibre supplement may also be of benefit. Please discuss this with your dietitian.

When increasing the amount of fibre you eat it is also important to drink enough fluid. Most adults need to have six to eight drinks per day (one-and-a-half to two litres). This can include a variety of drinks such as water, fruit juices, milk, tea or coffee etc.

Diet and diverticulitis

During an episode of acute diverticulitis, your appetite may be poor. It is also recommended to avoid foods which are poorly digested or high in fibre, such as onions, nuts, seeds, fruit and vegetable skins, wholegrain cereals etc. Try to stick to plain foods which do not irritate your bowel. See the table below for examples of low fibre foods to try.

It is very important that you continue to drink enough during this time in order to replace lost fluid. Once your symptoms have subsided, you can gradually return to eating a normal high fibre diet.

If your appetite remains poor and you are concerned about recent weight loss or being underweight, please discuss this with your dietitian. They will be able to give you advice on ways to make your diet more nourishing.

Low and higher fibre foods

Here are some examples of low and higher fibre foods from the various different food groups:

Sample high fibre meal plan

Breakfast

• All Bran, bran flakes, porridge, or muesli.
• Glass of fruit juice plus tea or coffee.

Mid-morning snack

• Fruit with the skin.
• Handful of dried fruit or nuts on its own or added to yogurt.
• Glass of water, milk or squash.

Lunch

• Sandwich using whole grain bread with meat, fish or cheese and salad vegetables.
• Chunky vegetable soup with added pulses.
• Baked beans with granary toast.
• Glass of water, milk or squash.

Mid-afternoon snack

• Rye crisp-breads, wholegrain bread with cream cheese, peanut butter, jam or hummus.
• Cup of tea or coffee.

Dinner

• Meat, chicken, fish or meat alternative.
• Wholemeal pasta, rice, potato with skin.
• Two to three portions of vegetables or a side salad.
• Glass of water, milk or squash.

Supper or dessert

• Puddings, scones, cakes, pastries made using wholemeal flour with dried or stewed fruit.
• Cup of tea, hot chocolate or malted milk.

Further information

• NHS www.nhs.uk
• CORE www.corecharity.org.uk

References

Manual of dietetic practice (4th Ed) 2005, Thomas B and Bishop J

Tarleton S and DiBaise J.  Low residue diet in diverticular disease: putting an end to the myth.  Nutrition in clinical practice 2011; 26:2 137-142

Rocco A, Compare D, Caruso F, Nardone G.  Treatment options for uncomplicated diverticular disease of the colon. Journal of Clinical Gastroenterology 2009: 43: 9: 803-808

Ravikoff J and Korzenik J.  The role of fibre in diverticular disease.  Journal of Clinical Gastroenterology 2011: 45:S1: S7-S11