New to Vitamin D? Start Here

A fat-soluble vitamin that controls how much calcium and phosphate the body absorbs.

Key takeaways

• Daily recommendation: 10 micrograms (400 IU)
• When: October to March for everyone; year-round for at-risk groups
• Most useful single change: Take 10 micrograms daily through autumn and winter.
• Commonest mistake: High-dose products bought without advice, since it is stored and accumulates.
• See a doctor if any of the signs under "When to speak to a doctor" below apply to you.

Why bother

UK sunlight is too weak between roughly October and March for skin to make any, so intake over winter comes from food and supplements or not at all.

Start here

Begin here, with two things rather than ten.

• Take 10 micrograms daily through autumn and winter
• Supplement year-round if you are rarely outdoors, cover your skin, or have brown or black skin

Then add these

Once the first two are automatic, these are worth adding.

• Check the dose on the bottle; products range from 10 to 250 micrograms
• Tell your GP what you take before blood tests

The numbers, in one place

Common early mistakes

• High-dose products bought without advice, since it is stored and accumulates
• Sunbeds, which carry skin cancer risk
• Assuming a summer holiday covers you through to spring

Where to go next

• Vitamin D: Common Myths and What Guidelines Say
• Answers to the Common Questions on Vitamin D
• Vitamin D — the reference entry
• Dietary Fibre: What Published Guidance Supports
• Dietary Protein: What the Evidence Actually Says

When to speak to a doctor

See a GP for bone pain, muscle weakness or fractures from minor falls. Speak to your GP before supplementing if you have sarcoidosis, kidney disease, a parathyroid disorder, or a history of high blood calcium or kidney stones.

Where this comes from

• NHS — Vitamin D
• Scientific Advisory Committee on Nutrition — Vitamin D and Health

How this page was put together

Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarised or generalised beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.

Medical disclaimer

This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to a GP, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 999.