Fiber Intake Calculator
Daily fibre target and how far typical diets fall short.
Used for the calorie-scaled target of 14 g per 1,000 kcal.
Fibre per day (Institute of Medicine)
38 g
Increase intake over a few weeks rather than overnight — the discomfort people blame on fibre is nearly always the speed of the change, not the amount.
How the Fiber Intake Calculator works
Fibre is the nutrient most consistently under-eaten in Western diets — typical intake is around half the recommendation. It feeds gut bacteria, slows glucose absorption, and is associated in large cohort studies with lower cardiovascular and colorectal cancer risk.
Not medical advice. This calculator gives a general estimate, not medical advice. It cannot account for your individual health, medical history, or medication. Talk to a qualified healthcare professional before acting on any result.
Frequently asked questions
How much fibre should I eat per day?
The Institute of Medicine sets 38 g daily for men and 25 g for women under 50, dropping to 30 g and 21 g after 50. A calorie-scaled alternative is 14 g per 1,000 calories, which adjusts sensibly for body size and appetite.
What is the difference between soluble and insoluble fibre?
Soluble fibre dissolves into a gel, slowing digestion and helping lower LDL cholesterol — oats, beans, apples and psyllium. Insoluble fibre adds bulk and speeds transit — wheat bran, vegetables, nuts. Most fibre-rich foods contain both, so a varied diet handles the split without planning.
Can I eat too much fibre?
Yes. Beyond roughly 50-70 g a day, bloating, gas and cramping are common, and very high intakes can interfere with mineral absorption. Increasing intake abruptly causes far more discomfort than the amount itself — raise it over a few weeks and drink more water alongside it.
Do fibre supplements work as well as food?
For regularity and cholesterol, psyllium performs well. For everything else, food wins: whole plant foods bring potassium, magnesium, polyphenols and a variety of fibre types that a single isolated supplement does not replicate.