Fiber intake calculator
How much fiber should you eat? Work it out from your daily calories using the Dietary Guidelines figure of 14 grams per 1,000 calories, or use the adult adequate intakes by sex and age, then compare with what you eat now.
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How to use it
- Choose whether to base the goal on calories or on sex and age.
- Enter your daily calories, or pick your group.
- Enter the fiber you eat now to see the gap.
How it works
By calories: goal (g) = calories ÷ 1,000 × 14. By group, the adult adequate intakes are fixed: 25 g (women) and 38 g (men) aged 50 and under, 21 g and 30 g aged 51 and over. The gap is the goal minus what you eat, never below zero, and the share is what you eat ÷ the goal.
Worked example
On 2,000 kcal the goal is 2,000 ÷ 1,000 × 14 = 28 g. If you eat 15 g now, you are 13 g short, at about 54% of the goal.
Good to know
Packaged food labels list fiber in grams per serving, so adding up a day takes a little tallying. Values here are general guidelines, not personal medical advice.
Frequently asked questions
How much fiber do I need a day?
The Dietary Guidelines for Americans suggest 14 grams per 1,000 calories, so about 28 g on a 2,000-calorie diet. The Institute of Medicine's adequate intakes for adults are 25 g for women and 38 g for men up to age 50, and 21 g and 30 g from age 51.
Why are there two methods?
One scales the goal to how much you eat, the other gives fixed values by sex and age group. They often land close together but not exactly; either is a reasonable target to aim for.
How do I add fiber safely?
Increase slowly over a few weeks and drink enough water, since a sudden jump can cause gas and bloating. Beans, lentils, oats, berries, vegetables and whole grains are common sources.
Is this medical advice?
No. These are general population guidelines. Some medical conditions call for a different fiber intake, so ask your doctor or dietitian if that applies to you.