SUN safety may increase the risks from heart attack and stroke far more than it reduces the risks from melanoma, British scientists have warned.
Researchers from Edinburgh and Southampton universities have found that sunlight exposure reduces blood pressure, one of the key risk factors for heart disease, which accounts for three in 10 deaths around the world.
“This finding has significant public health implications,” the team reports today in the Journal of Investigative Dermatology.
“Well-meaning advice to reduce the comparatively low numbers of deaths from skin cancer may inadvertently increase the risk of death from (much more) prevalent cardiovascular disease and stroke.”
Blood pressure tends to be higher during winter months and in countries further from the equator, with heart disease rates following the same pattern.
The British team believes nitric oxide molecules in the skin helps control blood pressure when they are activated by sunlight.
The researchers exposed 24 adults to a dose of UV equivalent to half an hour of sunlight “at noon on a sunny day in southern Europe”. They found it dilated their blood vessels and lowered average blood pressure readings by 3.5, while nitrate levels also changed.
Experiments with a foil space blanket ruled out heat as the cause, while the researchers could not replicate the effect by putting the subjects on a low nitrate diet.
The report said cardiovascular disease was about 40 times as deadly as skin cancer, claiming 1125 lives a year for every million people, compared with 26 due to melanoma.
But Cancer Council Australia chief executive Ian Olver said the study did not alter the basic message about sun safety.
“If the UV index is below three, we don’t believe you need to cover up,” Professor Olver said.
“There are many times during winter months, and early or late in the day during summer, when that would be the case.
“But there are 2000 deaths a year from skin cancer in Australia. We can’t water down the message that if the sun is intense enough to burn your skin, then you should cover up.”
He said people could only protect themselves from UV by avoiding intense sunlight.
Source: The Australian
Comment: It is probably not surprising if this information confuses you!
For many years we have been taught to avoid sun exposure because of the risk of the most serious form of skin cancer, called melanoma, even though it is not entirely clear – as with many cancers – what else besides sun exposure may be involved in causing it.
Now here is direct evidence that we may be more at risk from the development of other more common and potentially lethal diseases – we have swapped one problem for another.
Added to this is the press that vitamin D deficiency is getting, and its association with a range of diseases, but rather than telling us about balanced sun exposure to avoid this, we are marketed more medicine in the form of vitamin D supplementation.
Whatever happened to some simple holistic principles of common sense and balance, as advocated here in this article?
Do we have to await all the evidence (and will we ever get it) before dealing with the obvious?