Who gets vitamin D deficiency?

Vitamin D

Vitamin D deficiency means that there is not enough vitamin D in the body. Broadly speaking, this can occur in three situations:

1. The body has an increased need for vitamin D.
2. The body is unable to make enough vitamin D.
3. Not enough vitamin D is being taken in the diet.

Increased need for vitamin D

Growing children, pregnant women, and breast-feeding women need extra vitamin D because it is required for growth. So, vitamin D deficiency is more likely to develop in the following groups of people:

• Pregnant or breast-feeding women. Vitamin D deficiency is even more likely to develop in women who have had several babies with short gaps between pregnancies. This is because the body's stores of vitamin D get used up, and there is little time for them to be built up before another pregnancy.
• Breast-fed babies whose mothers are lacking in vitamin D, or with prolonged breast-feeding, as there is little vitamin D in breast milk. (Note: there are significant advantages to breast-feeding; you should not stop breast-feeding due to concern about vitamin D levels - your baby can simply have vitamin D supplements as drops by mouth.)

Situations where the body is unable to make enough vitamin D

People who get very little sunlight on their skin are also at risk of vitamin D deficiency. This is more of a problem in the most northern parts of the world where there is less sun. In particular:

• People who stay inside a lot. For example, those in hospital for a long time, or housebound people.
• People who cover up a lot of their body when outside. For example, wearing veils such as the niqab or burqa.
• People with pigmented (coloured) skins. This includes black and Asian people. Caucasian (white) people are less at risk.
• Strict sunscreen use can potentially lead to vitamin D deficiency, particularly if high sun protection factor (SPF) creams (factor 15 or above) are used. Nevertheless, children especially should always be protected from the harmful effect of the sun's rays and should never be allowed to burn or be exposed to the strongest midday sun.
• Elderly people have thinner skin than younger people and so are unable to produce as much vitamin D. This leaves older people more at risk of vitamin D deficiency.
• Some medical conditions can affect the way the body handles vitamin D. People with Crohn's disease, coeliac disease, and some types of liver and kidney disease, are all at risk of vitamin D deficiency.
• Vitamin D deficiency can also occur in people taking certain medicines - examples include: carbamazepine, phenytoin, primidone, barbiturates and some anti-HIV medicines.