Dietary Fiber Intake Calculator
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/5/2026
French health authorities (ANSES) recommend an intake of 30 g of fiber per day for an adult (a minimum of 25 g per EFSA). Consuming 15 g of fiber therefore represents 50% of this daily goal.
Explanation
Dietary fiber, found in vegetables, fruits, legumes, and whole grains, plays an important role in digestive transit but also in preventing several chronic diseases. The French food safety agency ANSES recommends an intake of 30 g of fiber per day for adult men and women, with a minimum of 25 g/day; this 30 g threshold was chosen because the reduction in risk of cardiovascular disease, type 2 diabetes, and certain cancers (colorectal, breast) is observed more consistently from this level onward, even though an effect sometimes starts to appear as early as 25 g/day. The European Food Safety Authority (EFSA), for its part, sets a minimum threshold of 25 g/day for healthy digestive transit. In practice, the average intake observed in the population often falls short of these recommendations, which is why it's worth tracking your own intake to identify the gap to close, favoring a gradual increase (a sudden jump in fiber can cause digestive discomfort) along with adequate hydration.
Example: 15 g of fiber consumed in a day
Inputs
Fiber consumed: 15 g.
Calculation
Percentage of the goal = (15 ÷ 30) × 100 = 50%.
Result
This intake represents 50% of the daily goal recommended by French health authorities.
Frequently asked questions
Which foods are richest in fiber?
Legumes (lentils, chickpeas, beans), whole grains (whole wheat bread, oats, brown rice), fruits (especially with the skin), and vegetables are the main sources of dietary fiber. Refined grain products (white bread, white rice) contain noticeably less than their whole-grain equivalents.
Why increase fiber intake gradually?
A sudden increase in fiber intake can cause temporary digestive discomfort (bloating, gas) while the gut flora adapts. It's generally recommended to increase intake gradually over several weeks, making sure to drink enough water, since fiber needs water to fully play its role in digestive transit.
Why do French authorities recommend 30 g while EFSA cites 25 g?
Both thresholds rest on the same scientific literature but with slightly different synthesis criteria: EFSA sets 25 g as the minimum sufficient for healthy digestive transit, while French authorities set 30 g because the risk reduction for several chronic diseases is observed more consistently at that level in studies. Both recommendations point in the same general direction, with the French threshold being slightly more ambitious.