How much fiber per day? Calculate your intake
Count your portions of fruit, vegetables, legumes, whole grains and seeds to estimate your daily fiber intake and the gap from your target.
Short answer
ANSES recommends 30 g of fibre per day for adults, while most people in France eat about 20 g. A meta-analysis for the WHO associates an intake of 25 to 29 g per day with a 15 to 30% lower risk of mortality and several chronic diseases. Increase gradually, in 5 g increments.
Calculator
Validated inputsYour typical day
Enter your usual portions, not your perfect day.
Estimated fiber
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g/day
Fiber score
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/100
Deficit
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relative to the target
Status
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quick read
Hydration
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impact on tolerability
Suggested progression
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g to add / step
Action plan
What the tool measures
The nutrient almost everyone eats too little of
Fibre is the part of plants that our enzymes cannot digest. Some is fermented by the gut microbiota, which produces short-chain fatty acids such as butyrate. Fibre improves bowel regularity, satiety and blood glucose after meals.
A series of meta-analyses published in The Lancet for the World Health Organization compared people with the highest and lowest fibre intakes. Those with the highest intake had a 15 to 30% lower risk of mortality, cardiovascular disease, type 2 diabetes and colorectal cancer. Benefits were most apparent from 25 to 29 g per day.
This calculator estimates your fibre intake from simple portions, without weighing your food.
Interpreting the result
Interpret without overpromising
- Below 20 g: low intake, common in France.
- 20 g up to your target: intermediate intake, with room to increase.
- Target reached: 30 g by default, the ANSES recommendation for adults.
The score shows the percentage of your target reached. It drops slightly if you drink little while eating a lot of fiber, because fiber needs water to work properly.
Calculation and assumptions
Methodology
- Estimated fiber = fruit × 3 g + vegetables × 2.5 g + legumes × 7 g + whole grains × 4 g + seeds and nuts × 2.5 g + psyllium × 5 g, per portion.
- These average values per portion are rounded from food composition tables.
- Gap = target − estimated fiber.
- Suggested increments = gap ÷ 5 g, between 1 and 5.
Sources consulted
Sources
- Reynolds et al. (2019) : Carbohydrate quality and human health, systematic reviews and meta-analyses
Meta-analyses for the WHO: 15 to 30% lower risk of mortality and chronic disease among those eating the most fibre, with a clear benefit at around 25 to 29 g per day.
- ANSES: Ciqual food composition table
French database of food fiber and nutrient content.
Scope of validity
Limitations to know
- The estimate depends on your actual portion sizes.
- A sudden increase can cause gas and bloating: increase by around 5 g per week and drink enough.
- If you have irritable bowel syndrome, inflammatory bowel disease or intestinal narrowing, discuss the type and amount of fiber with a professional.
- Psyllium can interfere with the absorption of some medicines: separate doses by at least two hours.
Frequently asked questions
Before using the result
How much fiber should you eat per day?
ANSES recommends 30 g per day for an adult. Meta-analyses show a clear benefit from 25 to 29 g per day, with some further benefit beyond that.
Which foods are highest in fibre?
Legumes such as lentils, chickpeas and beans, whole grains, chia and flax seeds, dried fruit, nuts, vegetables and whole fruit.
How can you increase fiber without bloating?
Add one source at a time, around 5 g more per week, and drink enough. Legumes are easier to tolerate in small, regular, well-cooked portions.
Does fibre help with weight loss?
They increase satiety and may help you eat a little less. In meta-analyses, high intake is associated with slightly lower weight, without dramatic effects.