Vitamin
Vitamin D
Vitamin D helps the body absorb calcium to keep bones, teeth and muscles healthy. Most is made in the skin from sunlight, so deficiency is common in winter — many people in the UK are advised to take a supplement.
What it is
Vitamin D is a fat-soluble vitamin that the body mostly makes when skin is exposed to sunlight, with smaller amounts from food.
What it does
It helps the body absorb calcium and phosphate, which are vital for healthy bones, teeth and muscles, and plays a role in the immune system.
Good sources
Sunlight on the skin (spring and summer), oily fish, egg yolks, red meat and fortified foods such as some spreads and cereals.
Deficiency and who is at risk
Deficiency is common, especially in winter, and in people who cover their skin, have darker skin, or spend little time outdoors. Severe lack causes soft bones — rickets in children and osteomalacia (bone pain) in adults. UK advice is that many people consider a daily supplement, especially in autumn and winter.
Balance
Can you have too much?
Very high doses from supplements over time can raise calcium to harmful levels, so it is important not to exceed recommended amounts.
Education and reference only. This is general nutrition information, not personal advice, and does not give doses. Ask a pharmacist, GP or registered dietitian before starting supplements, especially with a health condition or in pregnancy.
Answers
Vitamin D: frequently asked questions
Should I take a vitamin D supplement?
In the UK, many people are advised to consider a daily vitamin D supplement in autumn and winter, and some groups all year. Check current NHS advice or ask your pharmacist or GP.
What are the signs of vitamin D deficiency?
It is often silent, but can cause bone pain, muscle weakness and tiredness; severe deficiency causes rickets in children and bone softening in adults.
Related
More on vitamins and nutrition
Sources
Where this is drawn from
- NHS — Vitamins and minerals
- British Dietetic Association (BDA)
- UK Scientific Advisory Committee on Nutrition (SACN)
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