What does vitamin D do?

Vitamin D has several important roles, for example, it helps control the amount of calcium and phosphate in your body, which are needed to keep your bones and teeth healthy.

Having too little vitamin D (a deficiency) can damage the way your body absorbs calcium and phosphorus. In children, this can lead to rickets, a condition that can cause bone deformities, such as bowed legs. In adults, vitamin D deficiency can cause osteomalacia (weak bones), which can make bones painful and tender.

Where do I get vitamin D?

You get most of your vitamin D from sunlight on your skin. This is because the vitamin forms under your skin in reaction to sunlight. Vitamin D is also found in a small number of foods, including:

  • oily fish
  • eggs
  • fortified foods that have had vitamin D added to them, such as breakfast cereals and powdered milk

Who is at risk of vitamin D deficiency?

Most people can get all the vitamin D they need by eating a healthy, balanced diet and getting a little sun. However, the Department of Health recommends a daily vitamin D supplement for the following people:

  • all children aged six months to four years (see below)
  • all pregnant and breastfeeding women 
  • all people aged 65 and over 
  • people who aren’t exposed to much sun, for example people who cover up their skin for cultural reasons, or people who are housebound (stay indoors) for long periods of time

Vitamin D and babies and children

If you are exclusively breastfeeding your baby you should give your baby a daily vitamin D supplement from six months of age.

If your baby is fed with infant formula, you should give them a daily vitamin D supplement if they are drinking less than 500ml (one pint) of formula a day.

If you are breastfeeding your baby and giving them infant formula as well, they will need a daily vitamin D supplement from six months of age, or if they are drinking less than 500ml (one pint) of formula a day.

You should continue to give your child a vitamin D supplement until they are four years old.

For more information about vitamin D supplements for children, see vitamins for children. If you qualify, you can get vitamin drops containing vitamin D free from Healthy Start vitamins.

Getting advice

Talk to your GP if you’re concerned about the level of vitamin D you get from the sun and your diet. They can advise if you need a vitamin D supplement

Read the answers to more questions about healthy eating.

Further information:

Page last reviewed: 17/10/2012

Next review due: 16/10/2014