Fibre and Whole Grains: How Much You Need and Where to Find It

Nutrition basics · Published 2026-10-27

Bread rolls on a bakery counter above a hand-painted sign reading Fresh bread — Bread at a bakery. Photo by Clem Onojeghuo, CC0.

Fibre rarely makes headlines, but it is one of the clearest gaps between what people eat and what health bodies recommend. UK guidance asks adults to eat 30 g of fibre a day; the NHS says most manage only about 20 g. The good news is that closing the gap does not need special products: whole grains, pulses, vegetables, fruit, nuts and seeds do the work.

What fibre is and why it matters

Dietary fibre is the part of plant foods that the body does not fully digest in the small intestine. Part of it passes through largely unchanged, adding bulk; part is fermented by bacteria in the large intestine. Fibre is found only in plant foods: there is none in meat, fish, eggs or dairy.

The NHS says there is evidence that eating plenty of fibre is associated with a lower risk of heart disease, stroke, type 2 diabetes and bowel cancer, and that fibre helps digestion and prevents constipation. High-fibre foods also tend to be filling, and they often bring other nutrients with them, which is one reason why both the Eatwell Guide and the WHO put whole grains, pulses, vegetables and fruit at the centre of a healthy diet.

How much you need

Recommendations differ a little by country, but they point the same way:

UK: government guidelines say adults' fibre intake should increase to 30 g a day. Children need less: about 15 g at ages 2 to 5, 20 g at 5 to 11 and 25 g at 11 to 16, according to the NHS.
WHO: everyone older than 10 should aim for at least 25 g a day of naturally occurring dietary fibre from foods, with at least 15 g for children aged 2 to 5 and 21 g for those aged 6 to 9.
European Union: the European Food Safety Authority (EFSA) has set dietary reference values for fibre, part of its wider set of reference values for nutrients.

The NHS notes that most adults eat an average of about 20 g a day and that children aged 11 to 18 average around 16 g, so most people have room to add more.

Where fibre comes from

Whole grains

Whole grains keep the bran and germ of the grain, where much of the fibre is. The WHO gives unprocessed maize, millet, oats, wheat and brown rice as examples, and says carbohydrates should come mainly from whole grains, vegetables, fruits and pulses. The NHS suggests wholemeal or granary bread or higher-fibre white bread, wholewheat pasta, bulgur wheat, brown rice, porridge oats and plain wholegrain breakfast cereals.

Pulses

Beans, lentils and chickpeas are rich in fibre and protein and inexpensive, especially dried or tinned. The NHS suggests adding them to stews, curries and salads. They count as one of your 5 A Day, as explained in our 5 A Day guide, but the fibre benefit applies to every spoonful.

Vegetables, fruit and potatoes

Vegetables as a side dish or in sauces, fresh fruit, or fruit canned in natural juice for dessert all add fibre. Potatoes with their skins on, such as a baked potato or boiled new potatoes, are a good source too.

Nuts and seeds

A small handful of unsalted nuts, or seeds sprinkled on cereal or salad, adds fibre. The NHS suggests unsalted versions without added sugar.

What a high-fibre day can look like

The NHS gives example meals to show how the grams add up:

Breakfast: two slices of wholemeal toast with peanut butter and a medium orange, around 8.3 g.
Lunch: wholemeal spaghetti with a lentil and tomato sauce, around 11 g.
Dinner: grilled chicken breast with a skin-on baked potato, carrots and green beans, around 11.2 g.

Together that is roughly 30 g, before any snacks. The actual amount depends on how foods are made and how much you eat, so treat these as illustrations rather than targets.

Reading labels

Many pre-packed foods list fibre in the nutrition information. In the UK and EU, a food can be described as "high fibre" if it contains at least 6 g of fibre per 100 g, a threshold the NHS also uses. When choosing between breads or cereals, comparing fibre per 100 g is a quick way to pick the more wholegrain option. The ingredients list helps too: look for "wholemeal" or "wholegrain" near the start.

Adding fibre comfortably

Go gradually. A sudden large increase can cause wind and bloating. Adding one higher-fibre swap at a time gives the gut time to adapt.
Drink enough. Fluids help fibre do its job; the Eatwell Guide suggests 6 to 8 cups or glasses a day for most people.
Swap within meals you already like. Brown rice in a stir-fry, half wholemeal pasta, oats instead of a sugary cereal, beans in a soup.
Get it from food first. The WHO recommendation refers to naturally occurring fibre from foods. Fibre supplements are a different thing and are best discussed with a pharmacist or doctor, particularly if you take medicines.

People with some digestive conditions, such as irritable bowel syndrome or inflammatory bowel disease, may be advised to adjust the type or amount of fibre they eat. If you have ongoing digestive symptoms, or a change in bowel habits, see a GP rather than changing your diet on your own.

For how fibre-rich foods fit into the bigger picture, see a balanced plate.

Sources

NHS, "How to get more fibre into your diet": 30 g for adults, current intakes, children's needs, example meals, 6 g per 100 g.
World Health Organization, "Healthy diet" fact sheet: 25 g of naturally occurring fibre for everyone over 10; whole grains.
European Food Safety Authority, "Dietary reference values".
Scientific Advisory Committee on Nutrition, "Carbohydrates and Health" (2015, gov.uk).