UK Nutrient Gaps: What the National Diet and Nutrition Survey Shows

Data source: National Diet and Nutrition Survey (NDNS) 2019 to 2023, published by the Office for Health Improvement and Disparities and the Food Standards Agency. Fieldwork October 2019 to July 2023; 4,370 people from 2,925 UK households. Last checked: 25 October 2026.

The UK's own nutrition survey shows the biggest gaps in British diets are not exotic nutrients. They are fibre, fruit and veg, vitamin D in winter, iodine and folate in young women. Below are the headline numbers, with simple charts you are welcome to reuse with a link back to this page.

The UK nutrient gaps at a glance

Measure (NDNS 2019 to 2023)	Result
Adults meeting the 30g a day fibre recommendation	4% (average intake about 16g a day)
Adults eating 5 A Day	17% (adults 19 to 64 average 3.3 portions)
Adults 19 to 64 with low vitamin D status (below 25 nmol/L)	18% across the year; 21% to 38% of age groups 11+ in January to March
Adults 65+ with low vitamin D status	12%
Women 16 to 49 with urinary iodine below 50 µg/L	30% (adults 19 to 64: 25%)
Girls 11 to 18 with red blood cell folate below the deficiency threshold	17% (boys the same age: 7%)
Women 16 to 49 below the folate level linked to lower neural tube defect risk (748 nmol/L)	83%

Chart: how many UK adults meet the basics?

1. Fibre: the biggest gap

Only 4% of adults reach the 30g a day the government recommends. Average intake is about 16g, roughly half. Fibre comes from wholegrains, beans, lentils, fruit, vegetables, nuts and seeds; no gummy or tablet replaces those foods.

2. Fruit and vegetables

Fewer than 1 in 5 adults (17%) eat 5 A Day. Adults aged 19 to 64 average 3.3 portions a day.

3. Vitamin D in autumn and winter

18% of adults aged 19 to 64 and 12% of adults 65+ had low vitamin D status, and the figure peaks in January to March. The NHS advises everyone to consider a daily 10 microgram vitamin D supplement in autumn and winter, because UK sunlight is too weak to make enough from October to March. Vitamin D contributes to the normal function of the immune system and to the maintenance of normal bones.

4. Iodine in young women

Median urinary iodine for women aged 16 to 49 was 82 µg/L, and 30% were below 50 µg/L. Milk, dairy, fish and eggs are the main UK sources, so people who avoid them may need to plan their intake. Iodine contributes to the normal production of thyroid hormones.

5. Folate in teenage girls and women

17% of girls aged 11 to 18 had folate status below the deficiency threshold, more than twice the rate in boys. 83% of women of childbearing age were below the level associated with a lower risk of neural tube defects, which is why the NHS advises 400 micrograms of folic acid a day for anyone who could become pregnant. Folate contributes to maternal tissue growth during pregnancy.

What this means for you

• Food first: wholegrains, pulses, fruit, vegetables, dairy or fortified alternatives, and fish cover most of these gaps.
• Vitamin D is the one nutrient the NHS asks everyone to consider supplementing in autumn and winter.
• Supplements cannot fix a low-fibre diet. Be wary of any product that says it can.

GUUDIES is a daily pouch of six gummies, including a Daily Greens+ multivitamin with vitamin D3. Food supplements should not be used as a substitute for a varied, balanced diet and a healthy lifestyle.

Methodology

All figures are taken directly from the published NDNS 2019 to 2023 report (fieldwork years 12 to 15). NDNS is a continuous, nationally representative survey of food consumption and nutritional status in the UK, using food diaries plus blood and urine samples. Fieldwork paused from March to October 2020 because of COVID-19. We have not adjusted or re-weighted any figures. Thresholds: vitamin D below 25 nmol/L (risk of deficiency); red blood cell folate below 305 nmol/L (deficiency) and below 748 nmol/L (neural tube defect risk threshold for women); urinary iodine below 50 µg/L.

Source: National Diet and Nutrition Survey 2019 to 2023: report (GOV.UK).

Using this data

Journalists and bloggers are welcome to use these figures and charts with a credit link to this page. For comment from the GUUDIES team, email hello@guudies.co.

FAQ

What is the most common nutrient gap in the UK?

Fibre. Only 4% of adults meet the 30g a day recommendation in the latest NDNS.

How many people in the UK are low in vitamin D?

18% of adults aged 19 to 64 and 12% of adults 65+ had low vitamin D status across the year, rising to between 21% and 38% of age groups 11+ in January to March.

Where does this data come from?

The National Diet and Nutrition Survey, run for the UK government, which measured diets, blood and urine of 4,370 people between 2019 and 2023.