---
title: "UK Sunlight Cannot Make Enough Vitamin D From October to March: Who Should Take It and How Much"
description: UK sunlight cannot make enough vitamin D from October to March. How much to take, who needs it all year and how to choose a supplement.
author: Dr Marina Nani (Editor-in-Chief)
date: 2026-10-28T21:40:53.170Z
updated: 2026-10-28T21:43:24.046Z
canonical: https://richhealthmagazine.com/article/vitamin-d-winter-uk
image: https://cdn.nanimediahouse.com/pexels-35857959.webp
categories: Nutrition
content_type: Guide
publication: Rich Health Magazine
schema_type: Article
---

Your skin makes vitamin D when ultraviolet B rays from the sun reach it. From late March to the end of September, most people in the UK make all they need from [everyday time outdoors](https://richhealthmagazine.com/article/winter-daylight-mood). From October to early March, the sun sits too low in the sky. The UVB rays lose too much strength passing through the atmosphere, and your skin makes little or none, however long you stay outside.

Vitamin D helps your body absorb calcium and phosphate, the minerals that keep your bones, teeth and muscles healthy. A long shortfall in children can cause rickets, which softens and bends growing bones. In adults it can cause osteomalacia, which brings bone pain and muscle weakness.

You may have read that [vitamin D lifts mood](https://richhealthmagazine.com/article/holistic-lifestyle-changes-to-treat-vitamin-d-deficiency-and-depression) or prevents colds. The evidence on those claims is mixed. Its proven role is bones and muscles, and that alone makes a winter supplement worth taking.

## 1. Take 10 micrograms a day from October to March

UK health guidance advises adults and children over four to consider a daily supplement of 10 micrograms during autumn and winter. You may also see this written as 400 IU, the older unit. One microgram equals 40 IU.

## 2. Take it all year if you are in a higher-risk group

Some people do not make enough vitamin D even in summer. You should consider a daily supplement all year if you rarely go outdoors, live in a care home, usually cover most of your skin when you are outside or have dark skin, for example if your family comes from Africa, the Caribbean or South Asia. Darker skin makes vitamin D more slowly in weaker sunlight.

## 3. Give babies and young children their own dose

Breastfed babies from birth to one year need 8.5 to 10 micrograms a day. Babies who have more than 500ml of infant formula a day do not need a supplement, as formula is already fortified. Children aged one to four should have 10 micrograms every day, all year. Families on low incomes may qualify for free vitamins through the Healthy Start scheme, which covers pregnant women and children under four.

## 4. Choose vitamin D3 in most cases

Supplements come in two forms. Vitamin D3 is the form your skin makes, and it raises blood levels more reliably than vitamin D2, which comes from plants and fungi. Most D3 is made from lanolin in sheep's wool, so it is not vegan. If you avoid animal products, look for D3 made from lichen, which most health food shops and pharmacies stock.

## 5. Take it with a meal that contains some fat

Vitamin D dissolves in fat, and your body absorbs it better with food. Take your tablet with breakfast or dinner rather than on an empty stomach. Pick a time you will remember every day. Consistency matters more than the hour.

## 6. Eat the foods that contain it

[Oily fish such as salmon, mackerel, sardines and herring](https://richhealthmagazine.com/article/10-natural-sources-of-vitamin-d-that-men-include-in-their-nutrition-plan) are the richest food sources. Egg yolks, red meat and liver add smaller amounts, and some breakfast cereals and fat spreads are fortified. Food alone rarely provides 10 micrograms a day, so treat it as a top-up rather than a replacement for the supplement.

## 7. Do not take more than you need

More is not better with vitamin D. Over many months, very high doses can build up calcium in your blood, which can damage your kidneys, bones and heart. Adults should not take more than 100 micrograms a day, children aged one to ten no more than 50 micrograms and babies under one no more than 25 micrograms. Check the label if you take several products, as multivitamins, fish oils and calcium tablets often contain vitamin D too.

## 8. Speak to a pharmacist or GP if you have a health condition

If you have kidney disease, take medication for your heart or for epilepsy, or have been told your calcium levels are high, ask your pharmacist or GP before you start. Your GP can arrange a blood test if you have symptoms such as persistent bone pain or muscle weakness, but most people do not need a test before taking the standard 10 micrograms.

Sunbeds will not fix a winter shortfall. They raise your risk of skin cancer, and a tablet that costs a few pence a day does the job far more safely.