What causes it?

Over a lifetime, it's estimated the human gut digests more than 65 tonnes of food and drink. Much of this food will be low in fibre, putting the gut under strain.
One common outcome of this is diverticular disease, a condition affecting the large bowel, or colon, believed to be the result of too little fibre in the diet.
A diet low in fibre creates the ideal conditions for constipation to develop. When this happens, the pressure in the large part of the gut increases, which forces small parts of the gut lining outwards through the muscles surrounding the gut. This causes the lining to form small balloon-like pouches called

Who's affected

About one in two adults over 50 is affected, and most adults are affected by the time they reach 90. Men and women are affected equally.
Diverticular disease is very uncommon in countries such as Africa, where diets are high in fibre. In Western countries, where many people still don't eat enough fibre, it becomes more common as people get older.

How's it diagnosed

Unless the diverticula become inflamed, many people won't have any symptoms. They may only become aware they have diverticular disease when it's found by chance during tests for another problem.
Under these circumstances, to prevent future problems developing, it's advisable to increase the amount of fibre in the diet to avoid constipation.

What are the symptoms?

For many people, the diverticula don't cause any problems, but some people may need emergency surgery because the diverticula become inflamed.
When the diverticula are not inflamed, symptoms tend to come and go. Episodic cramping, abdominal pain, bloating and excess wind are common.
These are often accompanied by a change in normal bowel patterns, with constipation or diarrhoea, or both, alternating.
Dietary advice to increase the amount of fibre is essential. Increasing fluid consumption, becoming more active and always responding to your body's bowel movement signals lessen the chance of constipation.
Antispasmodic medication, peppermint tea and painkillers are recommended for use when needed.

What is diverticulitis?

Infection in the diverticula, possibly caused by an impacted piece of faeces, is responsible for the inflammation that develops. When this happens - called diverticulitis - the pain is very severe and usually felt in the lower left side of the abdomen.
A person will often feel feverish and have nausea and vomiting. They may pass blood rectally.
Someone with diverticulitis may be treated at home with painkillers, antibiotics, laxatives and dietary advice. But diverticulitis is often severe, and can need hospital treatment with antibiotics and fluids given through a drip.
In some cases, the bowel may perforate, become obstructed or bleed heavily. When this happens, the situation becomes an emergency and an operation may be needed.

Diverticulitis diet: What should I eat after an attack?

Answer

Diverticulitis occurs when small, bulging pouches (diverticula) in your digestive tract become infected and inflamed — causing severe abdominal pain, fever and nausea. Treatment of diverticulitis depends on the severity of your symptoms and whether this is your first attack. Mild cases of diverticulitis can be treated with changes in diet, rest and antibiotics. Severe cases may eventually require surgery to remove the diseased portion of your colon.
During a mild attack of diverticulitis, your doctor may recommend a clear liquid diet or a low-fiber diet. This helps the area of infection to heal.

Foods allowed on a clear-liquid diet include:

• Plain water
• Fruit juices without pulp
• Broth (bouillon or consumme)
• Gelatin Popsicles without bits of fruit or fruit pulp
• Tea or coffee without cream

Foods allowed on a low-fiber diet include:

• Enriched white bread
• White rice or plain pasta, noodles or macaroni
• Low-fiber cereals
• Most raw, canned or cooked fruits without skins, seeds or membranes
• Fruit juice with little or no pulp
• Canned or well-cooked vegetables without seeds, hulls or skins
  Tender meat, poultry and fish
• Eggs
  Smooth peanut butter
• Milk, yogurt or cheese without seeds or nuts
• Desserts without seeds or nuts

Once your symptoms improve — often within a few days — you can gradually increase the amount of fiber in your diet. Start by adding about 5 to 15 grams of fiber a day to allow your digestive system to adjust to the higher fiber intake.
To prevent attacks of diverticulitis:

• Eat more fiber. High-fiber foods, such as fresh fruits and vegetables and whole grains, soften waste and help it pass more quickly through your colon. This reduces pressure within your digestive tract. Aim for 25 to 30 grams of fiber a day. If you have a difficult time consuming this much fiber every day, consider using a fiber supplement, such as psyllium (Metamucil, Nature's Way) or methylcellulose (Citrucel).

• Drink plenty of fluids. Fiber works by absorbing water and increasing the soft, bulky waste in your colon. But if you don't drink enough liquid to replace what is absorbed, fiber can be constipating.

• Exercise regularly. Exercise promotes normal bowel function and reduces pressure inside your colon, decreasing your chances of forming diverticula.