How much fibre is 30 g? Build a day and see where you land
Most adults in the UK eat about 18 g of fibre a day, well under the 30 g that UK guidance recommends (EFSA considers 25 g adequate). Build a day of meals below and see where you land.
Fibre only comes from plants, and a few swaps (wholemeal instead of white, beans or lentils in a stew, fruit with breakfast) add up quickly. We also cover how to build up gradually and who should ask a doctor or dietitian first.
You have probably seen "30 g of fibre a day" on a label or in a news story. It sounds like a lot, because it is: most adults get well under it. The good news is that it adds up faster than you would think once you know which foods carry it. Build a day below and watch the number move.
How much fibre is enough?
Fibre is the part of plant foods your body cannot digest. UK guidance (the SACN report) sets 30 g a day for adults. EFSA, the European Food Safety Authority, considers 25 g a day adequate for normal bowel function and notes that intakes above that are linked to further health benefits. Both are population targets, not a pass or fail mark for any single day. Children need less: roughly 15 g at ages 2 to 5, 20 g at 5 to 11 and 25 g at 11 to 16.
UK adults currently average about 18 g a day, around 60% of the target. Higher fibre intakes are linked in large studies to lower risks of heart disease, type 2 diabetes and bowel cancer, though those studies show association rather than proof for any one person.
Where fibre hides
Fibre comes only from plants: whole grains, pulses (beans, lentils, chickpeas), vegetables, fruit, nuts and seeds. Meat, fish, eggs and dairy have none. There are two broad kinds. Soluble fibre (oats, beans, fruit) forms a gel in the gut. Insoluble fibre (wholemeal bread, bran, skins) adds bulk. Most plant foods contain both, so you do not need to count them separately.
The pairs in the calculator show the biggest easy wins. Wholemeal bread has about three times the fibre of white. Wholemeal pasta has more than double. A portion of lentils covers around a fifth of the day on its own.
Easy ways to add more
- Swap one white staple (bread, pasta) for the wholegrain version.
- Add a handful of berries or a piece of fruit to breakfast, and keep the skin on apples, pears and potatoes.
- Stir a few spoonfuls of beans or lentils into soups, stews and sauces.
- Choose a handful of nuts as a snack.
Aim for a mix of whole grains, pulses, vegetables and fruit across the day, and build up gradually.
Go slowly
If your usual intake is low, jumping to 30 g overnight can cause gas, bloating and cramps. Add one change every few days and drink fluids through the day, since fibre works best with enough water. Some bloating while your gut adjusts is common and usually settles.
Who should ask first
This is general information, not medical advice. If you have a bowel condition such as IBS, Crohn's disease or ulcerative colitis, have had bowel surgery or swallowing difficulties, or have been told to follow a low-fibre diet, talk to your doctor or a registered dietitian before changing how much fibre you eat. The same goes if you are pregnant or breastfeeding, take medication (fibre can change how some medicines are absorbed), or have or have had an eating disorder. If you notice blood in your stool, ongoing changes in your bowel habits or unexplained weight loss, see a doctor rather than adjusting your diet.