Foods high in fiber: the 14 best sources
Satiety, microbiome, blood sugar, cholesterol: few nutrients tick this many boxes. Yet most adults only reach half the target.
Why fiber changes everything
Fiber is the carbohydrate you don’t digest — which is precisely the point: it slows sugar absorption, feeds the microbiome (fermentable soluble fiber), boosts satiety and regulates transit (insoluble fiber).
The evidence is massive: every extra 8 g of daily fiber is associated with a notable drop in cardiovascular risk, type-2 diabetes and some digestive cancers. One of the highest-yield dietary levers there is.
The ranking: fiber per 100 g
Daily target used by Micron: 28 g per day for an adult.
| Food | per 100 g | per typical serving |
|---|---|---|
| 1Wheat branEaten in small amounts: scale the value down to a realistic serving of a few grams. | 43g154% | 1 tbsp (10 g)4.3g15% |
2 Chia seedsEaten in small amounts: scale the value down to a realistic serving of a few grams. | 34g121% | 1 tbsp (12 g)4.1g15% |
3 Popcorn (air-popped) | 14.5g52% | 1 serving (30 g)4.4g16% |
4 Almonds | 12.5g45% | 1 handful (30 g)3.8g13% |
5 Dark chocolate (70-85%) | 10.9g39% | 1 serving (20 g)2.2g8% |
6 Rolled oats | 10.6g38% | 1 serving (40 g)4.2g15% |
7 White beans (cooked) | 10.5g38% | 1 serving (150 g)16g56% |
8 Passion fruit | 10.4g37% | 1 serving (50 g)5.2g19% |
9 Artichoke (cooked) | 8.6g31% | 1 piece (120 g)10g37% |
10 Lentils (cooked) | 7.9g28% | 1 serving (150 g)12g42% |
11 Chickpeas (cooked) | 7.6g27% | 1 serving (150 g)11g41% |
12 Prunes | 7.1g25% | 1 serving (30 g)2.1g8% |
13 Raspberries | 6.5g23% | 100 g6.5g |
14 Green peas (cooked) | 5.5g20% | 100 g5.5g |
Values per 100 g. Wheat bran and chia are used by the spoonful (10-20 g) — even so, their contribution stays major.
Calculate your portion
Choose a food from the ranking and adjust its weight.
How to add fiber without the discomfort
- Increase GRADUALLY (over 2-3 weeks) and drink more: fiber absorbs water — that duo prevents bloating.
- Switch grains to whole versions one at a time (bread, rice, pasta): each swap adds 2-4 g per serving without changing habits.
- Legumes are the best fiber/protein/price deal: 3 servings a week transform your average.
- Keep the skin on organic fruits and vegetables (apple, pear, potato): it concentrates much of the insoluble fiber.
- Blending does not destroy fiber (a smoothie keeps it all) — juicing filters nearly all of it out.
How much fiber per day?
Micron uses a target of 28 g/day (customizable in the app). European and US references aim for 25-30 g — real average consumption stalls at 15-20 g.
The gap closes fast: an oat + chia breakfast (~8 g), one serving of lentils (~8 g) and two fruits (~5 g) nearly get you there on their own.
Track these intakes with Micron
Micron analyzes your meals and tracks 29 nutrients — iron, magnesium, vitamins, omega-3… Every day you see your % of target and what is actually missing.
Frequently asked questions
Which food contains the most fiber?
Wheat bran (43 g/100 g) is unbeatable, followed by chia seeds (34 g). On real servings, legumes (8-10 g/100 g cooked), passion fruit, raspberries and artichokes are the most effective contributors.
Soluble or insoluble fiber: do you have to choose?
No — they are complementary: soluble fiber (oats, legumes, apples) regulates blood sugar and cholesterol and feeds the microbiome; insoluble fiber (bran, whole grains, skins) speeds up transit. A varied diet naturally provides both.
Is too much fiber a thing?
Yes, especially if the increase is sudden: bloating, gas, discomfort — and beyond ~50-60 g/day, possible interference with some mineral absorption. The rule: gradual increase + hydration. IBS-prone guts should adjust fiber types with a professional.
More nutrients to explore
Data sources
Values from the USDA FoodData Central, CIQUAL (ANSES) composition tables and NIH fact sheets. Amounts vary with variety, origin and cooking — read them as reliable orders of magnitude, not lab-grade precision. CIQUAL ↗ · USDA FoodData Central ↗ · NIH ODS ↗
⚠️ This article is for information only and does not replace medical advice. Needs vary with age, sex and situation (pregnancy, conditions, medication): if in doubt or symptomatic, talk to a health professional.