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Sun, UV and cancer

Sun and vitamin D

A bit of sun helps our bodies make vitamin D, which is important for healthy bones, teeth and muscles. Find out about why you don’t need to sunbathe, vitamin D deficiency risk and taking supplements.

Do I need to sunbathe to get enough vitamin D?

No, you don’t need to sunbathe to get enough vitamin D.

A bit of sun helps our bodies to make vitamin D. The amount of sunlight we need to make vitamin D in the UK is different for each person. It depends on your skin tone and the time of day or year.

Infographic showing vitamin D activation according to skin tone.

Between mid-March and mid-October, short breaks in the sun should be enough for most people to make all the vitamin D they need. But remember, too much sun can cause sunburn and increase the risk of skin cancer. Learn about how to enjoy the sun safely.

We can also get vitamin D in our diet, from foods such as:

  • egg yolks

  • fresh or tinned oily fish (for example, mackerel or sardines)

  • fish liver oils

  • some margarines

  • fortified cereals, which have vitamins and minerals added

Should I take a vitamin D supplement?

In the UK, the NHS recommends people at risk of vitamin D deficiency take a 10 microgram (400 I.U.) supplement throughout the year.

People who are at higher risk of vitamin D deficiency include:

  • People with naturally darker skin tones, such as brown or black skin

  • People who spend very little time in the sun. For example, those who are housebound or in care homes

  • People who usually wear clothes that cover up most of their skin when outdoors

  • People over the age of 65

  • Pregnant and breastfeeding women

  • Babies and children aged under 4

The NHS also recommends that everyone takes a 10 microgram vitamin D supplement between October and March, when the sun’s rays are weaker.

Read more about NHS guidance on vitamin D supplements.

Does vitamin D deficiency cause cancer?

There isn’t enough convincing evidence to link low levels of vitamin D (vitamin D deficiency) to cancer. And there’s not evidence to support taking vitamin D supplements to reduce cancer risk.

But vitamin D deficiency can cause other health conditions, including rickets in children and bone problems in adults. If you are worried vitamin D deficiency, speak to your doctor.

Find out more

Find out ways to enjoy the sun safely

How does the sun and UV cause cancer?

Am I at risk of sunburn?

Last reviewed: 15 May 2024

Next review due: 15 May 2027

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