Research shows indoor types risk melanoma

By BILLY ADAMS in Sydney

It sounds like just what sun lovers have been dying to hear.

Researchers have discovered that people who spend much of their time indoors are more likely to contract the deadliest form of skin cancer than those who regularly soak up some rays.

But there is a sting in the tail. A sun tan is still unhealthy. The more time you spend in the sun, the bigger the risk to your health.

It's an intriguing paradox which first struck scientists in the 1970s.

While melanoma rates were highest in people with sensitive skin who lived in the most sun-kissed areas, office workers seemed more susceptible than beach lifesavers.

And tumours often developed on areas of the body normally hidden from the sun, such as the back.

The research which finally confirms this puzzling anomaly comes from New South Wales, a place with more than its fair share of sun and sand, and the highest reported rates of melanoma on Earth.

"The best way to explain this is to take two people who both have the same amount of sun exposure," says Bruce Armstrong, a professor of public health at the University of Sydney.

"One gets that exposure on a regular basis, similar amounts each day, but the other one only goes into the sun on an intermittent basis, maybe out on a boat.

"The second person is at much higher risk than the first."

After pooling the results of a number of studies around the world, Professor Armstrong has discovered that the second person is up to three times more likely to develop melanoma.

The reason is still not certain but research suggests that the cells which give rise to melanoma respond to sun exposure damage in a different way from cells which cause other types of skin cancer.

Australia has the highest rates of skin cancer in the world, affecting at least one in two people who spend all their lives there.

But sun lovers should continue to take stringent precautions. The statistics only compare favourably against people who spend the same amount of time in the sun, albeit on a more intermittent basis.

nzherald.co.nz/health