Health⏱ 5 min read
How to Calculate Your Daily Fibre Intake (and Why It Matters)
Most UK adults get about 18g of fibre per day — the recommended target is 30g. Here's how to count fibre, which foods are most efficient, and the difference between soluble and insoluble fibre.
Fibre is the nutrient most consistently under-consumed in Western diets, with strong evidence linking higher intakes to lower rates of cardiovascular disease, colorectal cancer, type 2 diabetes, and all-cause mortality. Yet it's often overlooked in nutrition tracking.
The UK Recommendation
UK Government recommendation:
Adults: 30g fibre per day
Average UK adult actual intake: ~18g/day
Children's targets:
Age 2-5: 15g/day
Age 5-11: 20g/day
Age 11-16: 25g/day
Age 16+: 30g/day
High-Fibre Foods Reference Table
FoodPortionFibre
Baked beans200g tin9.8g
Lentils (cooked)150g8.5g
Chickpeas (cooked)150g7.5g
Avocado1/2 medium (75g)5.0g
Oats (porridge, 50g dry)50g4.5g
Broccoli (cooked)80g2.6g
Wholemeal bread1 slice (40g)2.5g
Apple (with skin)1 medium (150g)2.4g
White bread1 slice (40g)0.7g
Brown rice (cooked)150g1.4g
Soluble vs Insoluble Fibre
Both types count toward your 30g target — but they have different mechanisms and benefits:
Soluble fibre (dissolves in water, forms gel):
- Sources: oats, beans, lentils, apples, berries, psyllium
- Slows digestion → reduces blood glucose spikes
- Feeds beneficial gut bacteria
- Lowers LDL cholesterol (beta-glucan mechanism)
- Reduces risk of type 2 diabetes and heart disease
Insoluble fibre (does not dissolve, adds bulk):
- Sources: wheat bran, most vegetables, wholegrains, nuts
- Speeds intestinal transit → reduces constipation risk
- Dilutes and removes potential carcinogens in the colon
- Reduces colorectal cancer risk
A Sample 30g Fibre Day
Breakfast:
Porridge (50g oats): 4.5g
Banana (120g): 2.0g
Lunch:
Lentil soup (200ml, 100g cooked lentils): 6.0g
Wholemeal bread (2 slices): 5.0g
Snack:
Apple: 2.4g
Handful mixed nuts (30g): 2.0g
Dinner:
Chickpea and vegetable curry:
Chickpeas 150g: 7.5g
Mixed vegetables 150g: 2.5g
Total: 31.9g ✓
Key pattern: legumes (beans, lentils, chickpeas) are the most
efficient way to hit 30g — far more so than vegetables alone.