Assorted dried beans and legumes

The UK Fibre Gap: How to Get From 16g to 30g a Day

10 min read

In the latest UK national diet survey, adults aged 19 to 64 ate an average of 16.4g of fibre a day. The government recommendation is 30g, and only 4% of adults met it. Large reviews link higher fibre intake to lower rates of heart disease, type 2 diabetes, bowel cancer and early death.

This guide covers what the survey found, what the evidence links fibre to, where UK fibre comes from, and how to reach 30g with everyday food, based on NHS examples.

4%
Share of UK adults who met the 30g a day fibre recommendation, 2019 to 2023
National Diet and Nutrition Survey (NDNS), GOV.UK
16.4g
Average daily fibre intake for adults aged 19 to 64
NDNS 2019 to 2023
25-29g
Daily fibre intake where risk reductions were greatest, in a Lancet review of 185 observational studies and 58 trials
Reynolds et al. 2019, The Lancet
9%
Lower cardiovascular disease risk linked with each extra 7g of fibre a day, in 22 observational cohort publications
Threapleton et al. 2013, BMJ
10%
Lower bowel cancer risk linked with each extra 10g of fibre a day, in 16 observational studies
Aune et al. 2011, BMJ
Sources: National Diet and Nutrition Survey 2019 to 2023. Reynolds et al. 2019, The Lancet. Threapleton et al. 2013, BMJ. Aune et al. 2011, BMJ.

How far short the UK falls

The National Diet and Nutrition Survey collected online 24-hour diet recalls on 4 days per person from October 2019 to July 2023, covering 2,296 adults and 2,074 children. Average fibre intake was below the recommendation in every age group: 16.4g a day for adults aged 19 to 64, 16.9g for those aged 65 to 74 and 16.4g for those aged 75 and over.

Average daily fibre intake, UK adults Grams a day by age group, against the 30g recommendation 16.4g 16.9g 16.4g 30g Aged 19 to 64 Aged 65 to 74 Aged 75 and over Recommendation
Source: National Diet and Nutrition Survey 2019 to 2023, 2,296 adults. The 30g recommendation is the government's target for the adult population average.

Children fell short too. The NHS says children aged 2 to 5 need about 15g a day, those aged 5 to 11 about 20g and those aged 11 to 16 about 25g. In the survey, children averaged 12.5g a day at 18 months to 3 years, 14.5g at 4 to 10 years and 15.4g at 11 to 18 years. The 30g day later in this guide is for adults.

Where UK fibre comes from

In the survey, cereals and cereal products were the main source of fibre in every age group, providing between 43% and 50% of daily intake. Vegetables came second, and fruit provided a smaller share for most age groups. In our view, that makes the type of bread, cereal, pasta and rice you buy a good place to start.

What higher fibre intake is linked to

A 2019 series of reviews in The Lancet on carbohydrate quality, including fibre, led by Andrew Reynolds at the University of Otago and funded in part by the World Health Organization, pooled 185 prospective studies, covering just under 135 million person-years, and 58 clinical trials with 4,635 adults. People who ate the most fibre had between 15% and 30% lower rates of death from all causes and from cardiovascular disease, and of coronary heart disease, stroke, type 2 diabetes and bowel cancer, than those who ate the least. In the trials, which measured risk markers rather than disease, higher fibre intake lowered bodyweight, systolic blood pressure and total cholesterol.

Risk reductions across several outcomes were greatest at around 25 to 29g a day, and the dose-response curves suggested higher intakes could bring more benefit. The authors rated the certainty of the fibre evidence as moderate, and their findings apply to the general population rather than people with chronic disease.

A 2024 meta-analysis in Clinical Nutrition, led by Fatemeh Ramezani, pooled 64 prospective cohort studies with about 3.5 million people.

Lower death risk with higher fibre intake Higher versus lower intake, percent lower risk, from a review of 64 cohort studies Any cause 23% Cardiovascular disease 26% Cancer 22%
Source: Ramezani et al. 2024, Clinical Nutrition, 64 prospective cohort studies, about 3.5 million people. Observational data, so these are associations, not proof of cause.

Insoluble fibre tended to show stronger links than soluble fibre, and fibre from whole grains, cereals and vegetables was linked to lower all-cause death risk. Fibre from nuts and seeds was linked to a 43% lower risk of cardiovascular death, though with a wide range of uncertainty.

Two earlier BMJ meta-analyses looked at dose. Diane Threapleton and colleagues at the University of Leeds pooled 22 cohort study publications and found each extra 7g of fibre a day was linked to a 9% lower risk of cardiovascular disease and of coronary heart disease. Dagfinn Aune and colleagues at Imperial College London pooled 25 prospective studies, 16 of which gave the total fibre estimate, and found each extra 10g a day was linked to a 10% lower risk of bowel cancer, with cereal fibre and whole grains showing the clearest links.

Most of this evidence is observational. People who eat more fibre may differ in other ways, so these studies show associations. The Reynolds authors noted that the cohort and trial findings agreed, and judged from the strong dose-response evidence that the links to several diseases could be causal.

"Implementation of recommendations to increase dietary fibre intake and to replace refined grains with whole grains is expected to benefit human health."
Reynolds et al. 2019, The Lancet

Variety of plants and the gut

The American Gut Project, published in 2018, analysed samples, mostly stool, from more than 10,000 citizen scientists, mainly in the US, UK and Australia. In self-reported diet data, the number of different plant types people ate was linked to the diversity of their gut microbes, more than labels such as vegan or omnivore. People who reported more than 30 types of plants a week had different gut microbes, and fewer of some genes that help bacteria resist antibiotics, than those who reported 10 or fewer. The plant analyses used smaller subsets of the group. This was a self-selected group and the data were associations, so it does not show that eating more plant types caused the difference.

A day that reaches 30g, from NHS examples

The NHS gives example meals with their fibre content. Put together, they reach about 30g in a day:

  • Breakfast: 2 slices of wholemeal toast with peanut butter and a medium orange, about 8.3g.
  • Lunch: wholemeal spaghetti with lentil and tomato sauce, about 11g.
  • Dinner: grilled chicken breast, a skin-on baked potato, carrots and green beans, about 11.2g.
  • Snack: a small handful of unsalted nuts such as almonds, some fruit, or crackers and hummus, to add more.

The NHS notes these are illustrations, as fibre content depends on how food is made and how much you eat. The NHS says high-fibre foods have 6g or more of fibre in every 100g.

Swaps that raise your fibre

These swaps come from the NHS. The order is ours, starting with cereals because they supply the largest share of UK fibre.

  • Choose a higher-fibre breakfast cereal, such as plain wholewheat biscuits, plain shredded whole grain, or porridge.
  • Go for wholemeal or granary bread, or higher-fibre white bread, and wholegrains like wholewheat pasta, bulgur wheat or brown rice.
  • Eat potatoes with their skins on, such as a baked potato or boiled new potatoes.
  • Add pulses like beans, lentils or chickpeas to stews, curries and salads.
  • Include plenty of vegetables with meals, as a side or added to sauces, stews or curries.
  • Snack on fresh fruit, vegetable sticks, rye crackers, oatcakes, and unsalted nuts or seeds. The NHS advises eating dried fruit with meals rather than between them, as it can increase the risk of tooth decay.

How to increase fibre comfortably

For constipation, the NHS advises increasing fibre gradually and drinking plenty of water and other fluids. Its bloating guidance notes that some foods, such as beans, lentils and cabbage, can cause gas. Our suggestion is to add one or two of the swaps above each week rather than all at once.

The NHS says to see a GP if you feel very bloated, are often bloated or it does not go away. Bloating can come from conditions such as coeliac disease, a food intolerance or irritable bowel syndrome, and bloating that does not go away can be a sign of something more serious, such as ovarian cancer. The NHS also lists blood in your poo, changes in your poo or how often you go that are not usual for you, and losing weight without trying among the symptoms of bowel cancer to see a GP about. Get these checked rather than changing your diet first.

In our view, if you have inflammatory bowel disease, irritable bowel syndrome, kidney disease, have had bowel surgery, or have another long-term condition, speak to your GP or a registered dietitian before raising your fibre.

Common mistakes

  • Relying on one food. The NHS advises getting fibre from a variety of sources.
  • Leaving bread, cereal and pasta refined. Cereals provide the largest share of UK fibre, so switching to whole grain versions is one of the easiest ways to raise your total.
  • Adding a lot at once without extra fluids. The NHS constipation guidance advises increasing fibre gradually and drinking plenty of fluids.

Frequently asked questions

How much fibre should I eat a day?
The government recommends 30g a day for adults. The NHS says children aged 2 to 5 need about 15g, aged 5 to 11 about 20g and aged 11 to 16 about 25g.
How much fibre do UK adults eat?
In the National Diet and Nutrition Survey for 2019 to 2023, adults aged 19 to 64 averaged 16.4g a day, and 4% of adults met the 30g recommendation.
Is there a benefit below 30g?
In the observational data, lower risk was linked to intakes below 30g as well. In the BMJ meta-analyses, each extra 7g or 10g a day was linked to lower risk. In the 2019 Lancet review, risk reductions were greatest at around 25 to 29g a day, and higher intakes may bring more benefit for heart disease, type 2 diabetes and some cancers.
What counts as a high-fibre food?
The NHS says high-fibre foods have 6g or more of fibre in every 100g. Check the nutrition label on the pack.
Will more fibre make me bloated?
The NHS bloating guidance notes that foods such as beans and lentils can cause gas, and advises seeing a GP if bloating is frequent or does not go away. Its constipation guidance advises increasing fibre gradually with plenty of fluids.

The bottom line

UK adults average about 16g of fibre a day against a 30g recommendation, and only 4% reach it. In large reviews, higher fibre intake was linked to lower rates of heart disease, type 2 diabetes, bowel cancer and early death, and trials found lower blood pressure, cholesterol and bodyweight, which are risk markers rather than disease outcomes. Switch to whole grain cereals and bread, add pulses and vegetables, keep potato skins on, and build up gradually with plenty of fluids.

Eat for the long term
DT Fitness London builds nutrition and training plans around what the research supports, with food you already buy.
Book a consultation at dtfitnesslondon.com

Related reading

Sources

Back to blog