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.
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 exposures 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.
You don’t need to spend hours in the sun to feel the benefits of sunlight. In fact, extra time in the sun doesn't mean you keep on producing more vitamin D. When your body has healthy levels of the vitamin any extra is just broken down.
This means that spending a long time in the sun will not give you any extra vitamin D. But it will increase your risk of skin cancer.
People who are most likely to be lacking in vitamin D include:
- people with naturally brown or black skin
- people who wear clothing that fully conceals them
- older people who don’t go outside much
- pregnant women
- breast-feeding babies with vitamin D-deficient mothers
- people who avoid the sun
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.
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