Vitamin D for bones

Vitamin D helps your body absorb and use calcium, which gives your bones their strength and hardness.

There are three ways you can get vitamin D:

• From sunlight
• From food
• From supplements

Low vitamin D levels could increase your risk of osteoporosis and broken bones. And a severe shortage of vitamin D causes rickets and osteomalacia, which is soft, weak bones.

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Sunlight

When the sun’s rays fall on your body, they react with your skin to make vitamin D. In the UK, your skin can only get vitamin D from sunlight from the beginning of April to the end of September. During this time, it's recommended you expose your skin to direct sunlight for around 10 minutes, once or twice per day.

Give your skin short periods in the sun, without sunscreen, while you're doing short outdoor tasks such as:

• hanging out the washing
• pulling up weeds
• walking to the shops.

Remember:

• If the weather is cloudy, it takes longer to produce the same amount of vitamin D as on a sunny day.
• Glass blocks the sun’s rays, so go outside or open your window.
• Darker skin produces vitamin D at a slower rate.
• Sunblock and high factor sunscreen stop the sun's rays reaching your skin. This reduces the amount of vitamin D your body makes.

Sunburn and skin damage

If your skin is exposed to the sun for more than 10 minutes, always use sunblock or sunscreen. And avoid exposing your skin to direct sunlight in the middle of the day when the sun it at its strongest. Don't be tempted to not wear sunscreen for long periods to increase your vitamin D levels – you may do more damage to your skin than good for your bones.

Babies and children have very sensitive skin, so need careful protection.

Food

There's a small amount of vitamin D in some foods, but it's difficult to get enough vitamin D from food alone. Foods containing vitamin D include:

• oily fish, such as herring, salmon and mackerel
• eggs
• some pork products
• lamb's liver
• fortified bread
• fortified yoghurts
• specially processed mushrooms.

Use our Vitamin D-rich food chooser to find more foods rich in vitamin D, and calculate how much you're getting each day.

Supplements

From the end of September to the beginning of April, you should consider taking a daily 10 microgram (sometimes called 400 International Units) vitamin D supplement. This is because you can't get vitamin D from the sun in winter.

You don't need blood tests to monitor your vitamin D levels before you start a supplement, or while you're taking one.

Do not take a higher dose than recommended, unless your healthcare professional tells you to. Too much vitamin D can be dangerous.

More information on supplements:

Find out more about mineral and vitamin supplements: 

Professor David Armstrong talks to us about mineral and vitamin supplements. 

Coronavirus pandemic and vitamin D

Public health advice is that you consider taking a daily supplement of 10 micrograms (sometimes called 400 units) of vitamin D during the pandemic.

This is not to reduce your risk of coronavirus. It is to help keep your bones and muscles healthy if you're at home more than you used to be. Spending more time indoors means you're getting less vitamin D from the sun.

You don't need blood tests to monitor your vitamin D levels before you start a supplement, or while you're taking one.

Do not take a higher dose than recommended, unless your healthcare professional tells you to. Too much vitamin D can be dangerous. Be reassured there is no risk of having too much vitamin D if you follow the advice of your healthcare professional.

If a healthcare professional has advised you to take vitamin D, you should continue with your normal dose. You don't need to take a bigger dose.

Speak to your healthcare professional if you're unsure.

Content reviewed: December 2018

(updated March 2022)