Foods high in Fiber
Plant carbohydrate the body can't digest. Feeds gut bacteria, slows sugar absorption, and supports regular digestion. UK adults: target 30 g/day.
About Fiber
Fiber is plant carbohydrate the body can't digest. It travels through the small intestine intact and reaches the large intestine where gut bacteria ferment it into short-chain fatty acids that nourish colon cells and shape immune signalling.
There are two functional types. Soluble fiber (oats, beans, fruit, psyllium) dissolves in water to form a gel, slows glucose absorption, lowers LDL cholesterol, feeds beneficial bacteria. Insoluble fiber (wheat bran, vegetable skins, whole grains) bulks stool and speeds transit time. Most foods contain a mix.
UK recommendation: 30 g/day for adults. The UK average is well below this, closer to 18 g. High-fiber diets are associated with lower risk of heart disease, type 2 diabetes, and colorectal cancer. Ramp intake up gradually, with water, to avoid bloating.
Foods high in fiber, psyllium, lemon peel, corn bran, and more
Ranked by how much you get per calorie, so foods are not rewarded for simply being dry or concentrated. Values from USDA FoodData Central, McCance & Widdowson's CoFID, ANSES Ciqual, and other public nutrition databases. Amounts in grams.
Per calorie is the default here because it answers what to eat: ranked purely by amount, a list of the richest foods fills up with dried and concentrated things nobody eats a plateful of. Switch to per 100 grams above if concentration is what you are after. Our foods low in fiber list is measured per 100 grams instead, and that is deliberate too: per calorie would reward a food for carrying plenty of energy and none of the nutrient, which puts cooking oil below lettuce on a low-sodium list.
- Psyllium, husk, dry, uncooked 44.93g per 100 grams
- Lemon peel, raw 36.65g per 100 grams
- Corn bran, crude 35.27g per 100 grams
- Chilli (chili), green, raw 29.82g per 100 grams
- Kakadu plum 25.17g per 100 grams
- Fungi, Cloud ears, dried 24.68g per 100 grams
- Samphire, raw 24.43g per 100 grams
- Artichoke, globe, cooked 23.38g per 100 grams
- Artichoke, globe, raw 23.37g per 100 grams
- Tea, black, dry 22.51g per 100 grams
- Cinnamon, dried, ground 22.13g per 100 grams
- Cereals ready-to-eat, SUN COUNTRY, KRETSCHMER Toasted Wheat Bran 20.65g per 100 grams
Common questions about Fiber
- How much fiber should I eat per day?
- UK recommendation: 30 g/day for adults. The UK average is closer to 18 g, a big chunk of the population doesn't reach the target.
- What's the difference between soluble and insoluble fiber?
- Soluble fiber (oats, beans, fruit, psyllium) forms a gel, slows glucose absorption, lowers LDL cholesterol, feeds beneficial gut bacteria. Insoluble fiber (wheat bran, vegetable skins, whole grains) bulks stool and speeds transit. Most foods contain a mix.
- Can fiber cause digestive problems?
- A sudden increase can cause bloating and gas. Ramp intake up gradually, with water. People with IBS or specific conditions may need to choose fiber types carefully.
- Does fiber really help with weight?
- Indirectly. High-fiber foods tend to be lower in calorie density and more filling per gram, which makes overeating harder. Fiber itself doesn't burn calories.