Vitamin D

Woman wears a straw hat in the sun

We all need vitamin D to build and maintain strong bones. Our bodies produce vitamin D when our skin is exposed to UV rays from the sun. This is the main source of this vitamin, but it can also be found in foods.

If you are lacking in vitamin D for a long time then your bones may soften. In serious cases this leads to rickets in children and a condition called osteomalacia in adults.

What is a good balance of vitamin D?

Sunlight is the main source of vitamin D, but it is also the main cause of skin cancer. The amount of time you need in the sun to make enough vitamin D is different for each person. It also depends on things like skin type, time of day, time of year, and where you are in the world. So it’s not possible to give a ‘one size fits all’ recommendation on how much sun is needed to make enough vitamin D. But most people should be able to make enough from short, casual exposure like you might get just by going about your daily life. Enjoying the sun safely, while taking care not to burn, should help most people get a good balance. You shouldn’t have to redden or burn your skin to make enough vitamin D.

People should get to know their own skin to understand how long they can spend outside before risking sunburn under different conditions.

Does more sun always mean more vitamin D?

No. You don’t need to spend hours in the sun to make more vitamin D. When your body has healthy levels of the vitamin, any extra is simply broken down. But spending longer in strong sun will increase your risk of skin cancer.

Who may not be getting enough vitamin D?

People who are most likely to be lacking in vitamin D include:

  • People with naturally brown or black skin, for example people of African, Afro-Caribbean or South Asian family origin
  • People who wear clothing that fully conceals them
  • People over the age of 65
  • Pregnant and breastfeeding women
  • Babies and children aged under 5
  • People who are housebound or confined inside for long periods of time, for example in hospital

The Government recommends that people within these groups should take a 10 microgram supplement of vitamin D a day. Talk to your GP about vitamin D supplements if you are worried about your vitamin D levels. Vitamin D is also present in foods such as eggs, fatty fish, fish liver oils and some fortified cereals.

Vitamin D consensus statement

Cancer Research UK teamed up with other health organisations to bring together evidence on vitamin D.

It is endorsed by the British Association of Dermatologists, Cancer Research UK, Diabetes UK, the Multiple Sclerosis Society, the National Heart Forum, the National Osteoporosis Society and the Primary Care Dermatology Society.

Download the Vitamin D consensus statement

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