Almost 30,000 cases of breast and colon cancer a year could be prevented by Britons spending more time in the sun to boost vitamin D levels, say researchers.
A new study claims vitamin D "deficiency" may be to blame for 600,000 cancer cases worldwide each year, particularly in northern European countries where sun exposure levels are relatively low.
The US research - which comes amid the wettest summer since records began in Britain - recommends 10-15 minutes a day in the sun to maximise natural defences against cancer as vitamin D is made in the body in response to solar exposure.
There is mounting evidence that vitamin D could play a vital role in helping prevent disease, with the sun helping top up natural levels more effectively than through diet.
Although most people living in northern Europe are not sufficiently lacking in vitamin D to be classified as deficient, some experts believe blood levels should be higher to optimise health.
In the latest research Dr Cedric Garland and colleagues at the Moores Cancer Center at the University of California, San Diego estimate that 250,000 cases of colorectal cancer and 350,000 cases of breast cancer could be prevented worldwide by increasing intake of vitamin D3.
Dr Garland, a cancer prevention specialist, said: "For the first time we are saying that 600,000 cases of breast and colorectal cancer could be prevented each year worldwide, including nearly 150,000 in the US alone."
In the UK, which has one-fifth of the US population, a similar prevention strategy would reduce cancer cases by 30,000 a year.
The study combined data from surveys of blood levels of vitamin D during winter from 15 countries, along with satellite measurements of sunshine and cloud cover.
Source - Daily Mail