Adequate vitamin D levels are thought to have a protective effect, decreasing cancer melanoma risk and mortality. People who are avoiding exposure to sunlight and using sunscreens assiduously can be at risk of vitamin D deficiency.

It is estimated that about 15 minutes of sunlight a day on unprotected skin (e.g. arms and face) is enough to meet the body’s vitamin D requirements. However, in the UK, from mid-October until the beginning of April, there is insufficient UVB for skin synthesis of vitamin D and therefore taking supplements should be considered in order to account for this defecit.

The National Institute for Health and Care Excellence (NICE) now recommends that all UK adults take a daily supplement containing 400 international units (IU) – 10 micrograms – of vitamin D throughout the year. Pregnant and breastfeeding women eligible for the NHS Healthy Start scheme can obtain free vitamin tablets.