Should you take vitamin D? Who needs it and how much

Vitamin D helps your body absorb calcium and phosphate, which keep your bones, teeth and muscles healthy. Most of it is made in your skin when it's exposed to sunlight. The trouble is, in the UK the sunlight isn't strong enough for most of the year.

Why the UK is different

From late March or early April to the end of September, most people can make enough vitamin D from being outdoors. But between October and early March, the sun isn't strong enough, and it's hard to get enough from food alone. Only a few foods, such as oily fish, red meat, egg yolks and fortified foods, contain vitamin D.

Who should take a supplement?

UK health advice is that everyone should consider taking a daily vitamin D supplement during autumn and winter.

Some people are advised to take one all year round, because they're unlikely to get enough from sunlight even in summer. This includes people who:

• aren't often outdoors, for example if they're frail or housebound
• live in a care home
• usually wear clothes that cover most of their skin when outdoors
• have dark skin, for example people of African, African-Caribbean or South Asian background

How much do you need?

For adults and children over 1, the recommended amount is 10 micrograms (400 IU) a day.

Babies and young children have their own guidance. Breastfed babies are usually advised to have a daily supplement of 8.5 to 10 micrograms from birth, and children aged 1 to 4 should have 10 micrograms a day. Babies having more than 500ml of formula a day don't need a supplement, because formula is already fortified. A health visitor or pharmacist can help you choose the right product for your child.

How much is too much?

Taking too much vitamin D over a long time can cause too much calcium to build up in the body, which can weaken bones and damage the kidneys and heart. For most adults, don't take more than 100 micrograms (4,000 IU) a day. The limits for children are lower.

Our Vitamin D3 softgels contain 25 micrograms (1,000 IU) each, which is within the safe daily limit for adults. If you also take a multivitamin, check how much vitamin D it contains and add the two together.

Some people can't safely take vitamin D supplements, including people with certain kidney conditions or high calcium levels. If you have a medical condition or take other medicines, ask a pharmacist or GP first.

Tips for taking it

• Take it at the same time each day so it becomes a habit, for example with breakfast.
• Vitamin D is fat-soluble, so taking it with a meal can help your body absorb it.
• You can't get vitamin D from sitting by a sunny window, because glass blocks the rays your skin needs.
• In summer, short periods of sun on your skin help, but always cover up or use sunscreen before you start to redden or burn.

The short answer

Most people in the UK should consider taking 10 micrograms of vitamin D a day from October to March, and some people should take it all year round. Stay under 100 micrograms a day, and check with a pharmacist if you have a health condition.