When we think about our vitamin and mineral intake, it's easy to just focus on our diets. But did you know we get most of one essential vitamin - vitamin D - from the sun? Here's everything you need to know about the sunshine substance...

What is Vitamin D?

It's produced in our bodies when UV rays hit our skin and helps our bodies absorb calcium, which is vital for healthy bones.

Am I getting enough?

Those most at risk from vitamin D deficiency are people with naturally brown or dark skin, people who wear clothes which cover the whole body and block the sun, and people who don't spend time outside, perhaps due to age, illness or disability. If you're worried that you might not be getting enough vitamin D, see your GP.

How do I get enough?

Just spend some time in the sun. There's no set time you need to spend in the sunshine - it varies from person to person, and depends on whether you're in St Tropez or Scarborough! But you should never spend so long in the sun that you allow yourself to burn. If you get enough Vitamin D during the sunny months, you'll store enough in your body to see you through the winter.

How do I stay safe in the sun?

Whenever you spend time in the sun, make sure you take the precautions recommended by Cancer Research UK's Sun Safety campaign to avoid burning - wear sunscreen, cover up and sit in the shade.

Can I get it from food?

Yes - small quantities are present in oily fish such as mackerel, sardines or salmon, egg yolks and fortified breakfast cereals. Supplements are also available, though it's best to ask your GP before you take them.