http://www.vitamindcouncil.org

For a number of reasons, many people aren’t getting enough vitamin D to stay healthy. This is called vitamin D deficiency. You may not get enough vitamin D if:

• You don’t get enough sunlight. Your body is usually able to get all the vitamin D it needs if you regularly expose enough bare skin to the sun. However, many people don’t get enough sunlight because they spend a lot of time inside and because they use sunscreen. It’s also difficult for some people to get enough vitamin D from the sun during the winter.
• You don’t take supplements. It’s very difficult to get enough vitamin D from the foods you eat alone.
• Your body needs more vitamin D than usual, for example if you’re obese or pregnant.

Are certain people more likely to have vitamin D deficiency?

There are some groups of people that are more likely to have vitamin D deficiency. The following people are more likely to be lacking in vitamin D:

• People with darker skin. The darker your skin the more sun you need to get the same amount of vitamin D as a fair-skinned person. For this reason, if you’re Black, you’re much more likely to have vitamin D deficiency that someone who is White.
• People who spend a lot of time indoors during the day. For example, if you’re housebound, work nights or are in hospital for a long time.
• People who cover their skin all of the time. For example, if you wear sunscreen or if your skin is covered with clothes.
• People that live in the North of the United States or Canada. This is because there are fewer hours of overhead sunlight the further away you are from the equator.
• Older people have thinner skin than younger people and this may mean that they can’t produce as much vitamin D.
• Infants that are breastfed and aren’t given a vitamin D supplement. If you’re feeding your baby on breast milk alone, and you don’t give your baby a vitamin D supplement or take a supplement yourself, your baby is more likely to be deficient in vitamin D.
• Pregnant women.
• People who are very overweight (obese).