saudigastro.com/patients/diet-diverticular-disease
Category
Common
Red flags
5
This article is educational and does not replace your doctor's advice. Seek urgent care for any red-flag symptoms.
What is it?
Diverticula are small pouches that bulge out through weak spots in the wall of the large bowel (colon). Having them is called diverticulosis and is usually silent. Diverticular disease means they cause symptoms such as cramping pain and altered bowel habit. Diverticulitis means one or more pouches become inflamed or infected, causing pain (typically low on the left), fever and sometimes complications such as an abscess. Diet is part of preventing problems and recovering from an attack.
How common is it?
Diverticulosis becomes more common with age and is found in a large share of older adults in Western countries; it is increasingly seen in younger adults as well. Only a minority of people with diverticula ever develop diverticulitis (commonly quoted as roughly 1 to 4 in 100 over some years).
Why does it happen?
It is linked to ageing of the bowel wall, constipation and straining, and a low-fibre diet. Other risk factors are obesity, smoking, lack of physical activity, a diet high in red and processed meat, and regular use of non-steroidal anti-inflammatory painkillers (NSAIDs such as ibuprofen or diclofenac). Genetics also play a role.
Symptoms
- Crampy lower abdominal pain, often on the left, eased by passing wind or stool
- Bloating and gas
- Constipation, diarrhoea or alternating bowel habit
- During diverticulitis: constant pain, fever, nausea, loss of appetite
- Small amounts of bright red blood in the stool (painless) can occur
Red flags — seek urgent medical care
Severe or worsening lower abdominal pain with fever
Possible diverticulitis or a complication. See a doctor the same day or go to the emergency room.
Hard, rigid belly, severe pain on movement, or vomiting
May indicate perforation or blockage. Go to the emergency room immediately.
Heavy rectal bleeding, passing clots, dizziness or fainting
Diverticular bleeding can be serious. Call emergency services.
Passing gas or stool in the urine, or from the vagina
Possible abnormal connection (fistula). See a doctor urgently.
Persistent change in bowel habit, weight loss or anaemia
Needs tests to exclude other conditions, including bowel cancer. Do not assume it is only diverticula.
How is it diagnosed?
Diverticulosis is often found by chance at colonoscopy or CT. Diverticulitis is diagnosed from symptoms, examination, blood tests (inflammation markers) and usually a CT scan. A colonoscopy is often advised some weeks after an attack, particularly if complications occurred or if you have not had a recent colonoscopy, to be sure no tumour is hidden.
What the latest science says
The AGA clinical practice guideline and clinical practice update on diverticulitis (2021), the ASCRS guideline (2020) and NICE guideline NG147 (2019) advise a diet rich in fruit, vegetables, whole grains and legumes, regular exercise, healthy weight, stopping smoking and avoiding regular NSAIDs. Nuts, corn, popcorn and seeds do not need to be avoided: a large cohort study of US men found no increased risk and possibly lower risk. High intake of red meat is associated with higher risk. Honestly, most evidence on diet comes from observational studies; randomised trials showing that extra fibre cures symptoms or prevents attacks are limited, and NICE noted weak evidence. Antibiotics are no longer routine for mild uncomplicated attacks in selected patients, and a clear-liquid diet is often used briefly but strong evidence for it is lacking.
Outlook — what to expect
Most people with diverticulosis never have serious problems. Most attacks of diverticulitis settle with simple treatment, though some people have repeat attacks and a few need surgery. A healthy diet and lifestyle may lower the chance of problems, but they cannot guarantee that attacks will not return.
Treatment
Habits & Lifestyle
Lifestyle changes that also protect your heart and weight help the bowel too.
- Be active: aim for about 150 minutes of brisk activity a week, such as walking.
- Aim for a healthy weight; excess belly fat is linked to a higher risk of diverticulitis.
- Stop smoking.
- Avoid regular use of ibuprofen, diclofenac and similar painkillers unless your doctor advises; low-dose aspirin for the heart should not be stopped without medical advice.
- Do not strain on the toilet and do not ignore the urge to go.
Diet
Between attacks, aim for a fibre-rich diet; during an attack, follow your doctor’s advice and widen your diet as symptoms ease.
- Build up to about 25 to 30 grams of fibre a day (your dietitian can set a target). Increase slowly over several weeks to limit gas and bloating, and drink enough fluids (roughly 6 to 8 cups of water or unsweetened drinks daily unless your doctor limits fluids).
- Good fibre sources: oats, whole wheat bread, brown rice, bulgur, barley, lentils, chickpeas, beans (ful), fruit with skin where tolerated, vegetables, and dates in moderate portions.
- You do not need to avoid nuts, seeds, popcorn or fruit skins to prevent diverticulitis.
- Eat less red and processed meat (for example, sausage, luncheon meat); choose fish, poultry and legumes more often.
- During an acute attack: your doctor may suggest clear fluids for a short time, then a low-fibre (low-residue) diet, and then a gradual return to a high-fibre diet after you recover. Do not stay on a low-fibre diet long-term.
- If you cannot reach enough fibre from food or it causes symptoms, a bulk-forming fibre supplement (such as psyllium) can be discussed with your doctor.
Medications
Medicines are chosen by your doctor depending on whether you have symptoms or an acute attack.
- Bulk-forming laxatives can help if constipation persists despite diet.
- Simple pain relief such as paracetamol is preferred; avoid NSAIDs and opioids unless prescribed.
- Antibiotics are used for more severe, complicated or higher-risk diverticulitis, and are not always needed for mild attacks in otherwise healthy people.
- Mesalamine and rifaximin are not recommended routinely to prevent attacks; probiotics have not been shown to help.
Procedures & Surgery
Procedures are for complications or repeated severe attacks.
- Colonoscopy a few weeks after an attack to check the bowel.
- Drainage of an abscess through the skin guided by a scan, or in hospital with IV antibiotics.
- Surgery to remove the diseased section is considered for perforation, fistula, blockage, or after repeated attacks, based on your individual situation rather than the number of attacks alone.
- Endoscopic or interventional treatment for diverticular bleeding when it does not stop on its own.
Living with the condition
- Keep a short diary of foods that bother you; avoid only what truly triggers your symptoms.
- Make sure you are up to date with bowel cancer screening.
- Have a plan: know the warning signs and where to go.
In the Saudi context
Refined white bread and rice dominate many meals, so swapping part of them for whole wheat bread, brown rice, bulgur, freekeh, ful and lentils is a practical step. Salads, vegetable stews and fruit after meals add fibre. Drink more water in the hot months. During Ramadan, people with uncomplicated diverticular disease can usually fast; include fibre-rich foods and water between iftar and suhoor to prevent constipation, and speak to your doctor if you are recovering from an attack or have complications.
Questions to ask your doctor
Save this list or print it before your appointment — doctors appreciate prepared patients.
- How much fibre should I aim for, and how fast should I increase it?
- Which foods, if any, should I avoid?
- Do I need a colonoscopy after my attack?
- Is it safe to use my pain medicines (NSAIDs, aspirin)?
- When would surgery be considered for me?
Trusted resources
Was this guide helpful?
Status: Approved for publication by SGA; individual clinician review is ongoing · Published 24/04/2026
For general education only; it does not replace your doctor’s advice. Individual clinician review of this guide is ongoing. SGA clinician? Review this guide