How sunshine can help your body fight disease
By Fiona Macrae
A spot of sunshine doesn't just lift your spirits, it also boosts your immune system.
Research shows that vitamin D, made when our skin is exposed to sunlight, plays a key role in activating white blood cells that protect the body from flu, food poisoning and even cancer.
Without the 'sunshine vitamin', the cells do not join the fight against disease.
Vitamin D, created when skin is exposed to the sun, can help protect the body from disease
Seek and destroy: Vitamin D, created when skin is exposed to the sun, can help protect the body from disease
The discovery could help in the development of vaccines and ways to combat auto-immune diseases and cancer.
It is well known that vitamin D is vital for calcium absorption and bone health and some studies have suggested it has an anti-cancer effect.
But scientists had not realised what a crucial role it played in the immune system.
A series of laboratory tests showed that the vitamin triggers dormant white blood cells into turning into 'killers' that seek out and destroy infections. Other
white blood cells turn into 'helpers' that enable the immune system to build a 'memory' of the infection, allowing it to mobilise more quickly on the next encounter.
Researcher Carsten Geisler, of the University of Copenhagen, said: 'If the T-cells (white blood cells) cannot find enough vitamin D in the blood, they won't even begin to mobilise.'
The discovery, documented in the journal Nature Immunology, could shed new light on conditions caused by immune system malfunctions, such as multiple sclerosis and organ transplant rejections.
Although vitamin D is found in foods such as oily fish and eggs, most of that found in the body comes from sunlight exposure, and many of us simply do not have enough.
In England, half the population is low in the vitamin when winter ends. In Scotland, it is two-thirds.
