Vitamin D has a number of functions, the most well established being the maintenance of healthy bones. Recently it has been suggested that it may also protect against diseases such as heart disease and some forms of internal cancer
Concerns have been raised regarding the potential risk of vitamin D deficiency in association with sun protection, as UVB is required for vitamin D synthesis. However, dermatologists still recommend the sensible use of sun protection including sunscreen during prolonged periods of exposure and/or exposure when the sun is high in the sky. During the summer months most people will achieve adequate vitamin D levels through incidental UV exposure. Deliberate unprotected exposure at peak times, is not recommended due to the known risks of skin cancer.
People at risk from vitamin D deficiency include those with darker skin (especially if they cover up, for example for religious reasons), the elderly, individuals who are housebound, or people who avoid the sun due to skin disease. If you are concerned that you may be at risk of vitamin D deficiency, a simple blood test will check your vitamin D level. The current recommended level of Vitamin D in blood is 60-80 nmol/l.
How much vitamin D is enough?
It is advisable that people who avoid the sun should take vitamin D. The recommended daily allowance is 1000 IU (25 micrograms) per day, but this may be higher in cases of severe vitamin D deficiency.
Foods that are naturally rich in vitamin D include fatty fish, eggs and some yoghurts and cereals which have had vitamin D added. If you eat reasonable quantities of these foods you may not need to take supplements every day.