Foods and home measures

• Oral rehydration solution from the pharmacy is the most important treatment for diarrhoea; juices and fizzy drinks do not replace it.
• For constipation: two green kiwifruit a day, or about 10 prunes a day.
• Enough water through the day, especially in summer and when taking fibre.
• True long-fermented sourdough bread: long fermentation reduces the sugars that cause gas, so some people with IBS tolerate it better than ordinary bread. Look for simple ingredients (flour, water, salt) with no added yeast. It contains gluten, so it is not suitable for coeliac disease.
• Laban, yoghurt and kefir: many people with lactose intolerance tolerate them better than milk, and kefir taken with H. pylori treatment improved results in one trial.
• Ground flaxseed or chia seeds with water for constipation.
• A spoon of olive oil daily may soften stools.
• During short-term diarrhoea: banana, rice and toast are easy to digest, but there is no need to limit yourself to them for more than a day or two.
• Manuka honey: kills H. pylori in the laboratory only; this has not been shown in patients. It is expensive, raises blood sugar like any honey, and can worsen IBS. It does not replace H. pylori treatment.
• Dates: high in fibre and may help constipation, but more than two can worsen bloating in IBS, and they raise blood sugar.

• Asafoetida (hilteet): used for gas; never give it to infants, avoid it in pregnancy, and the powder usually contains wheat flour, so avoid it with coeliac disease.
• Cardamom, cinnamon and fresh mint: safe in food amounts; mint can worsen heartburn, and avoid high-dose cinnamon capsules.
• Bone broth: nourishing and soothing, but no evidence that it "heals" the gut.
• Coconut water: hydrating, but it does not replace oral rehydration solution in severe diarrhoea.
• Hijama (cupping): no evidence of benefit for digestive diseases. If you choose it, use a licensed centre only, and ask your doctor first if you take immune-suppressing medicines or blood thinners, or have anaemia.

Not recommended

• Colon cleansing, "cleansing" enemas and coffee enemas: no benefit, and they can cause dehydration, salt imbalance or bowel injury.
• "Detox" diets, cleansing juices, and fasting for days to "rest the gut".
• Herbal-shop mixtures with unknown ingredients; some damage the liver or contain hidden drugs.