Fiber

How much fiber do you need per day?

Updated 4 Nov 2026

Short answer

Adults need about 25 to 38 g a day from all food, depending on the source and on sex. The US adequate intake is 25 g for women and 38 g for men, or 14 g per 1,000 kcal.[1] EFSA, the EU food safety authority, says 25 g for adults. The World Health Organization (WHO) says at least 25 g after age 10.[2][3]

Most people eat less. US adults average about 17 g a day, and about 94% of the US population falls short.[1] A large review found the greatest fall in disease risk at 25 to 29 g a day from food, and its dose-response curves suggested that more could add benefit.[4]

Children need less. The WHO says at least 15 g a day at ages 2 to 5 and at least 21 g at ages 6 to 9.[3]

Sources (4)

  1. The Role of Dietary Fiber in Health Promotion and Disease Prevention: A Practical Guide for Clinicians. Daley SF, Vadakekut ES StatPearls, 2026. PMID 32644459
  2. Scientific Opinion on Dietary Reference Values for carbohydrates and dietary fibre. European Food Safety Authority, 2010. www.efsa.europa.eu
  3. Healthy diet. World Health Organization. www.who.int
  4. Carbohydrate quality and human health: a series of systematic reviews and meta-analyses. Reynolds A, Mann J, Cummings J, Winter N, Mete E, Te Morenga L Lancet, 2019. PMID 30638909

More about fiber

What is fiber?How does fiber lower cholesterol?What is fiber used for?How long does fiber take to lower cholesterol?Is fiber safe?Is fiber from food better than a fiber supplement?

For education; not medical advice. Talk to a doctor before you start, stop or change a supplement.