Vitamin D (UK guide)

Why everyone in the UK should consider vitamin D from October to March, how much to take a day, foods with vitamin D and signs of deficiency.

Last reviewed: October 2026 · How we check our content

Vitamin D in the UK

10 mcg

(400 IU) a day is the UK recommendation for everyone over 1

Oct–Mar

UK sunlight is too weak to make enough vitamin D

~1 in 6

UK adults has low vitamin D levels (NDNS)

100 mcg

(4,000 IU) a day is the maximum for adults unless advised

What vitamin D does

Bones and teeth

Helps the body absorb calcium and phosphate.

Muscles

Needed for normal muscle function.

Immune system

Plays a role in normal immune function.

Foods with vitamin D

Food	Portion	Vitamin D
Salmon	100 g	~5–10 mcg
Mackerel / sardines / herring	100 g	~5 mcg
Eggs	2 large	~3 mcg
Fortified breakfast cereal	30 g	~1–2 mcg
Fortified spreads or plant milks	Varies	Check label
Red meat / liver	100 g	small amounts
UV-exposed mushrooms	80 g	Varies

Who should take it all year

People who are rarely outdoors or live in a care home
People who cover most of their skin when outside
People with dark skin (African, African-Caribbean or South Asian background)
Breastfed babies from birth (8.5–10 mcg) — formula is already fortified

Possible signs of deficiency (see a GP)

Bone or muscle pain and weakness
Tiredness
Frequent infections
In children, bone deformities such as rickets

World health facts

All facts

~2B

People lacking key micronutrients

Around 2 billion people lack essential vitamins and minerals such as iron, zinc, iodine and vitamin A.

Source: WHO

30%

Women 15–49 with anaemia

Nearly a third of women of reproductive age are anaemic, often due to iron deficiency.

Source: WHO 2023

40%

Young children with anaemia

About 40% of children aged 6–59 months worldwide have anaemia.

Source: WHO 2023

~1B

People low in vitamin D

Around a billion people are vitamin D deficient — common in the Middle East despite the sun, due to covered skin and indoor life.

Source: Nutrients reviews

More in Eat Well

Healthy Eating Healthy Nutrition Food Guide Functional Foods Supplements High Protein Foods Foods High in Fibre Healthy Snacks High Protein Meals Eatwell Guide Foods High in Iron Foods High in Magnesium Is It Healthy? Smart Kitchen Recipes

Questions people ask

How much vitamin D should I take a day in the UK?

The NHS advises 10 micrograms (400 IU) a day, especially from October to March. Do not take more than 100 micrograms a day without medical advice.

What does vitamin D do?

It helps keep bones, teeth and muscles healthy by regulating calcium and phosphate, and supports the immune system.

What foods have vitamin D?

Oily fish, egg yolks, red meat, liver and fortified foods such as some cereals and spreads. It is hard to get enough from food alone.

Sources

• NHS: Vitamin D
• SACN Vitamin D and Health (2016)
• NHS: Vitamin D deficiency
• Royal Osteoporosis Society

General information based on UK public health sources, not medical advice. Speak to your GP, pharmacist or a registered dietitian before major diet changes or starting supplements, especially if you are pregnant, have a health condition or take medication.