The virtues of Vitamin D: It's time we saw the light
It may not be the first supplement to be called a "wonder vitamin", but it is one of the few to have lived up to the name. Last week, the biggest review of the role of vitamin D in health found that people who took supplements of the vitamin for six years reduced their risk of dying from all causes.
It was the proof that researchers had been waiting for. Earlier studies had suggested that vitamin D played a key role in protecting against cancer, heart disease and diabetes – conditions that account for 60 to 70 per cent of all deaths in the West. The new study, by scientists from the International Agency for Research on Cancer in Lyon and the European Institute of Oncology in Milan and published in Archives of Internal Medicine, shows that it does.
Vitamin D is important because we are often short of it. Most healthy individuals get all the vitamins and minerals they need from eating a balanced diet, but vitamin D is the exception. It is made by the action of sunlight on the skin, which accounts for 90 per cent of the body's supply. Very little comes from food.
But the increasing use of sunscreens and the decreasing amount of time spent outdoors, especially by children, has contributed to what many scientists believe is an increasing problem of vitamin D deficiency.
How to get it – and how much you should take
* 90 per cent of the body's supply of vitamin D is generated by the action of sunlight on the skin.
* Vitamin D lasts for around 60 days in the body, so it needs regular topping up.
* Twenty minutes twice a week in the sun with exposed hands, arms and face is adequate to maintain reserves.