Vitamin D

Woman wears a straw hat in the sun

We all need vitamin D to help 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.

The government recommends people at risk of having low vitamin D levels take a supplement, and that everyone think about doing this over the winter.

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.

People with darker skin tones might need longer in the sun, but also have a lower risk of sunburn and skin cancer. Most white people should be able to make enough vitamin D from short, casual exposure without sun protection 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.

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 usually wear clothes that covers up most of their skin when outdoors
  • People over the age of 65
  • Pregnant and breastfeeding women
  • Babies and children aged under 5
  • People who aren’t often outdoors, for example in hospital or often housebound

The Government recommends that people within these groups should take a 10 microgram supplement of vitamin D a day throughout the year.

Between October and the end of March the Government also recommend people in the UK consider taking a daily vitamin D supplement. Your body makes vitamin D much less in the winter months in northerly countries such as the UK because the UV isn’t as strong. In summer some vitamin D may be stored to help maintain levels across the year. 

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 egg yolks, oily fish like mackerel and sardines, fish liver oils and some fortified cereals.


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