What is diverticulitis? And could the diverticulitis diet help you?

Ten per cent of people over 45 reportedly suffer from the condition.
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  • Diverticulitis is a painful digestive condition that occurs when the diverticula in your large intestine become inflamed. One the most notable and least-invasive preventative treatments is the diverticulitis diet. 

    Full of high fibre foods including fruits, vegetables and cereals, the diverticulitis diet aims to help with the symptoms of diverticular disease and stop those with the condition developing the more severe form, diverticulitis.

    According to the NHS, diverticula are small bulges or pockets that can develop in the lining of the intestine as you get older. While most people with diverticula don’t experience any symptoms (diverticulosis), others have lower tummy pain and are symptomatic (diverticula disease). If the diverticula go on to become inflamed or infected, causing more severe symptoms – such as severe stomach pain, a high temperature or diarrhoea or constipation – then it becomes diverticulitis.

    It was reported by Bupa that one in 10 adults over the age of 45 suffer with the condition. Last year, Masterchef judge Gregg Wallace revealed to the Mirror that he was one of them, explaining how he had been left “almost doubled up in pain” on one occasion.

    READ MORE: Walking for weight loss: how walking can help you shed the pounds without going on a diet

    The disease is notably made worse by certain types of food, as Gregg admitted that he had taken his eye off the ball food-wise around the time of the flare up. He said, “When they’re [the diverticula] irritated, you’ve got to watch alcohol and spicy food. We were eating chillis yesterday. Before that I had a massive skinful of beer in Dublin – and it was already playing up.”

    what is the diverticulitis diet

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    While there are many diets that encourage weight loss like the the Copenhagen Diet, the diverticulitis diet is different in the sense that it aims to prevent a medical condition getting worse. Similar diets include the gluten-free diet, which helps those with coeliac disease.

    What is the diverticulitis diet?

    The diverticulitis diet is a nutritional therapy programme recommended by many doctors to those who have diverticula disease to prevent it developing into the more severe diverticulitis. It is the best way to manage the condition according to gut-health charity Guts UK! who say, “The main treatment is to keep stools relatively soft and bulky. This may reduce the likelihood of more diverticula developing and may reduce the risk of hard pellets of faeces lodging within the pouches.

    “The best way to do this is to eat more fruit and vegetables, nuts, wholemeal bread and pasta, wholegrain cereals and brown rice, which are all good sources of fibre. The aim is to have at least one high fibre food with each meal, five portions of fruit or vegetables per day and try to drink at least two litres (eight to ten cups) of fluid every day.”

    Here’s what to eat on a sample day following the diverticulitis diet…

    diverticulitis diet

    Credit: Getty


    • fruit juice
    • wholemeal bread or toast with boiled egg, or spread (butter, jam without pips etc)


    • tuna sandwich with wholemeal bread
    • plain or flavoured yoghurt (avoid fruit yoghurts with pips)
    • piece of fruit


    • vegetable soup
    • chicken with steamed potatoes (without the skin) and vegetables.
    • fruit

    What foods trigger diverticulitis?

    Diverticulitis is an infection or inflammation of the diverticula. If you have been diagnosed with this, rather than diverticula disease, then you should stay away high-fibre foods to prevent further irritation to the diverticula.

    The NHS suggests that it might be best to avoid nuts, popcorn and seeds such as sunflower, caraway, pumpkin and sesame seeds to reduce the risk of blockage or irritation. It’s also suggested that you avoid foods with a high FODMAP including fruits like apples, pears and plums, dairy and fermented foods, beans, cabbage, Brussels sprouts and onions and garlic. You should also stay away from any red meats.

    If you have diverticula disease, to avoid triggering diverticulitis you should eat a high-fibre diet consisting of 30g of fibre per day, avoiding processed foods.

    Vegetables to avoid on the diverticulitis diet

    Some vegetables are also restricted on the diet. As advised by the NHS it’s best to avoid the following vegetables:

    • cucumber
    • radishes
    • whole tomatoes
    • peas
    • lentils
    • peppers
    • onions
    • sweet corn
    • beansprouts
    • broad and baked beans
    • jacket potatoes

    If you have diverticulitis and experience a flare up, a severe version of the opposite is advised to temporarily ease the pressure on the digestive system. It involves maintaining a fluid-only diet for a few days until the symptoms subside.

    Then, in the next couple of days while you are recovering, you should stick to very low-fibre foods in order not to irritate your digestive system.

    Once the symptoms have fully subsided, you can return to a regular, higher-fibre diet. From here you should aim to eat about 30g of fibre a day, according to NHS guidelines.

    diverticulitis diet

    Credit: Getty

    What causes diverticulitis?

    Diverticula normally develop when weak places in the colon give way under pressure, allowing the diverticula to come through the colon wall. This happens, according to Guts UK! when stools become “small and hard” instead of “soft and bulky”.

    They have difficulty passing through the intestine as it has to squeeze much harder than usual to push them along. It’s these contractions creating high pressure over a long period of time that weakens the lining of the colon, resulting in diverticular disease.

    What other factors can cause diverticulitis?

    The National Institute of Diabetes and Digestive and Kidney Diseases also suggests that genes play an important role, with some studies suggesting that people are genetically more likely to have the condition if someone else in their family has developed it.

    Obesity, smoking and a lack of exercise have also been shown to increase the likelihood of diverticulitis.

    How do you stop a diverticulitis flare up?

    If you have diverticulitis and have recovered from a recent flare up, the way to avoid another one is through your diet.

    • Eat more vegetables and fruit. These are high in fibre, which helps to avoid a flare of diverticulitis, but be careful not to introduce high fibre into your diet suddenly.
    • Drink plenty of fluids. Aim for eight glasses of water a day to ensure you’re staying hydrated.
    • Avoid refined and processed foods.
    • Increase exercise. This can help to encourage regular bowel movements, which are important for avoiding a diverticulitis flare up.

    As with all severe changes in your health, you should consult your doctor first. If you have not been previously diagnosed with diverticular disease or diverticulitis, then you may need to be tested for the disease.

    What other treatments are there for diverticulitis?

    According to Guts UK! there are two other possible treatment options for diverticulitis…


    While there is no specific medical treatment for the symptoms of diverticular disease, supplements which contain fibre such as ispaghula husk or methyl cellulose will help soften the stools. If in doubt, consult your pharmacist.

    Some doctors might prescribe an antispasmodic drug, says the charity but they say that the results are often disappointing.


    Surgery for diverticulitis is often only done after an episode of inflammation, says Guts UK!, because an abscess has formed around the colon or an infection from the diverticula has spread through the abdomen.

    The surgery involves cutting out a segment of the infected bowel, then one of the bowel is brought up to the skin as a stoma where the bowl content comes into the bag. It’s a treatment that can be reversed at a later date if the inflammation isn’t too severe and the bowel can be joined back together.