Vitamin D: everything you need to know about this supplement – from when to take it, to how much you really need

When the days shorten and the sun sinks low in the sky, that familiar winter slump sets in. There’s a fundamental reason for this seasonal fatigue: low levels of vitamin D – the “sunshine vitamin”.

People in the UK simply can’t make enough of this vital nutrient from sunlight during winter, which is why…

© La Conversation - mardi 10 février 2026