Fibre and the gut: eating for digestive health

How much fibre?

What we know

Diets higher in fibre are associated with a lower risk of heart disease, stroke, type 2 diabetes and bowel cancer. Fibre also helps keep bowel movements regular and feeds gut microbes.

Where it comes from

Good sources include wholegrain bread, cereals and pasta, oats, potatoes with their skins, beans, lentils and chickpeas, vegetables, fruit, nuts and seeds. The NHS Eatwell Guide suggests basing meals on higher-fibre starchy foods and eating at least five portions of fruit and vegetables a day.

Increasing it comfortably

• Increase fibre gradually over a few weeks. A sudden change can cause wind and bloating.
• Drink plenty of fluids, as fibre works best with water.
• Spread fibre-rich foods across the day rather than in one large meal.

When the advice is different

It depends

For some people with irritable bowel syndrome (IBS), more fibre is not always better. NICE advises that people with IBS should be discouraged from eating insoluble fibre such as bran, and that soluble fibre such as oats or ispaghula may be better tolerated. If fibre seems to make your symptoms worse, speak to your GP or a registered dietitian rather than cutting out whole food groups.

Supplements and "gut health" products

What we don't yet know

Foods and drinks marketed for gut health vary widely in what they contain. For most people, a varied, fibre-rich diet is better supported by evidence than any single product.

References

1. NHS. How to get more fibre into your diet. Accessed 29 September 2026.
2. NHS. The Eatwell Guide. Accessed 29 September 2026.
3. National Institute for Health and Care Excellence. Irritable bowel syndrome in adults: diagnosis and management (CG61).