What fibre does
Fibre is the part of plants your own enzymes can’t digest. Soluble fibre (oats, beans, chia) forms a gel that slows sugar absorption and lowers cholesterol; insoluble fibre (whole grains, vegetable skins) keeps things moving. Your gut bacteria ferment fibre into short-chain fatty acids that nourish the gut lining.
How much
Most guidelines recommend 25–38 g a day — and most people eat far less. High-fibre diets are linked to lower rates of heart disease, type 2 diabetes and bowel cancer.
Plant sources
Legumes, whole grains, vegetables, fruit, nuts and seeds. Animal foods contain none.
How many portions of each food would cover a day's fibre?
Tips
Increase fibre gradually and drink enough water, so your gut has time to adjust. See Legumes.