How much fibre do you need each day?

The short answer

• 25g

  Of fibre a day at least, for adults (World Health Organization, 2023)

• 25–29g

  A day: the range linked with the biggest health benefits, in a review of 185 studies

• 15–30%

  Lower risk of heart disease, type 2 diabetes, bowel cancer and early death in people who ate the most fibre

• 12–18g

  What US adults typically ate a day, in the survey the US experts used

Key findingAim for at least 25 g of fibre a day from food. Pulses, whole grains, millets, vegetables, fruit and nuts are the best sources. Most people eat far less than this.

What is fibre?

Fibre is the part of plant foods your body can’t digest. It is found in whole grains, dal and other pulses, vegetables, fruit, nuts and seeds. Meat, fish, eggs and milk have none. (In the US, it is spelled “fiber”.)

Because you don’t digest it, fibre passes through your gut. Some kinds turn thick and sticky. These slow down how fast food leaves your stomach and help you feel full. They can also lower the rise in blood sugar after a meal, and lower cholesterol. Other kinds add bulk to your stools and ease constipation.

How much fibre each day? What the guidelines say

The World Health Organization (WHO) says adults should eat at least 25 g a day of fibre that comes naturally in food. For children, it suggests at least 15 g at ages 2–5, 21 g at ages 6–9 and 25 g from age 10.

The US and Canadian advice is higher for men: 38 g a day for men and 25 g for women up to age 50. After 50, it is 30 g for men and 21 g for women. These amounts come from a simple rule: 14 g of fibre for every 1,000 calories you eat. On a 2,000-calorie day, that is 28 g (our calculation).

India’s 2024 dietary guidelines don’t give one number for adults. Instead, they advise more fibre-rich foods: whole grains, millets, pulses, nuts and vegetables.

Many people fall well short. In the US survey the experts used, men ate about 16–18 g a day and women about 12–14 g.

What the big review found

This review compared people who ate the most fibre with those who ate the least. Most of its data come from studies that followed large groups of people over time. This kind of study shows a link. It can’t prove that one thing causes the other.

The more fibre, the lower the risk. Each extra 8 g a day went with about a 10–20% lower risk across most outcomes. That 8 g is about what 70 g of raw dal or other pulses gives (our calculation).

WHO looked for harms too. Apart from one link with womb cancer, rated very low certainty, it found no downsides at 25 g a day or more. Few studies looked at more than 40 g a day.

Does fibre help you lose weight?

A little. In 27 trials with 2,495 people, eating more fibre lowered body weight by 0.37 kg on average, compared with eating less. Most trials lasted less than 6 months. They also showed small drops in blood pressure and LDL (“bad”) cholesterol.

So there is no special amount of fibre for weight loss. The US experts found no strong proof that fibre on its own changes fullness or weight. Still, India’s guidelines note that fibre slows digestion and helps you feel full, so fibre-rich meals fit well in a weight-loss plan. To set a calorie target, use the calorie deficit calculator.

Fibre in Indian foods

Of the foods you eat in large amounts, pulses carry the most fibre, then nuts, millets and cereals. Milk, eggs, meat and fish have none. Polishing rice and refining flour into maida removes some fibre.

How much is that in a day? India’s sample day of meals, “My Plate for the Day”, uses 250 g of cereals and millets, 85 g of pulses, 400 g of vegetables, 100 g of fruit and 35 g of nuts and seeds (raw weights, for a vegetarian day of about 2,000 calories). With the averages above, that gives about 38 g of fibre (our calculation), well above the 25 g minimum.

Whole fruit beats juice, because juicing removes the fibrous pulp.

Claims and evidence

• ClaimYou only need fibre if you’re constipated.

  EvidenceFibre does ease constipation. But people who ate the most fibre also had lower rates of heart disease, type 2 diabetes and bowel cancer.

• ClaimFruit juice is as good as whole fruit.

  EvidenceIndia’s guidelines say whole fruit is better, because juicing removes the fibrous pulp.

• ClaimA fibre supplement does the same job as fibre-rich food.

  EvidenceWHO’s advice is for fibre that comes naturally in food. The review behind it left supplement trials out, so the benefits were seen with food.

• ClaimMore than 30 g of fibre a day is too much.

  EvidenceNo upper limit has been set. The data hinted at extra benefit above 30 g a day, though fewer studies covered that range.

What this means for you

What the research can’t tell you yet

• Links, not proof. The disease results come from studies that followed people over time. People who eat more fibre may have other healthy habits too.
• Short trials. Most fibre trials lasted less than 6 months and measured things like weight and cholesterol, not disease.
• Where the studies were done. Most were in Europe and North America, with only a few elsewhere.
• High intakes. Few studies looked at more than 40 g a day.
• Children. WHO’s numbers for children are worked out from adult data.

How Bodyvault uses this research

Bodyvault’s automatic fibre target is 14 g for every 1,000 calories in your calorie target, the same rule as the US advice. On a 2,000-calorie target, that is 28 g. If you log food on at least 3 days and your 7-day average falls below 70% of your target, the Coach suggests easy swaps: whole dals, rajma, chana, vegetables, fruit with the peel and millets.

General information about fitness and nutrition, not medical advice. If you have a health condition, are pregnant or take medication, talk to your doctor before changing your diet or training.