Wednesday, May 08, 2013

A Dermatologist's Worst Nightmare

Bonnie: Dermatologists are in lock step when it comes to the sun: avoid it like the plague! Unfortunately, this is very bad advice. Yes, being smart about sun exposure is crucial. But getting sun exposure is a necessity. At least 15 minutes without sunscreen, five days a week, is ideal.

Dermatologists will have their chance to lay into researchers at the University of Ediburgh, who's landmark study tosses the mantra on its ear when presented this week at the International Investigative Dermatology conference, the world's largest gathering of skin experts.

According to the researchers, exposing skin to sunlight may help to reduce blood pressure, cut the risk of heart attack and stroke - and even prolong life. They have found that when our skin is exposed to the sun's rays, a compound is released in our blood vessels that helps lower blood pressure. 

The findings suggest that exposure to sunlight improves health overall, because the benefits of reducing blood pressure far outweigh the risk of developing skin cancer. Heart disease and stroke linked to high blood pressure are estimated to lead to around 80 times more deaths than those from skin cancer.

Production of this pressure-reducing compound - called nitric oxide - is separate from the body's manufacture of vitamin D, which rises after exposure to sunshine. Until now it had been thought to solely explain the sun's benefit to human health.

Researchers studied the blood pressure of volunteers who sat beneath tanning lamps for two sessions of 20 minutes each. In one session, the volunteers were exposed to both the UV rays and the heat of the lamps. In the other, the UV rays were blocked so that only the heat of the lamps affected the skin.

The results showed that blood pressure dropped significantly for one hour following exposure to UV rays, but not after the heat-only sessions. This shows that it is the sun's UV rays that lead to health benefits.

Dr Richard Weller, Senior Lecturer in Dermatology at the University of Edinburgh, said: "We suspect that the benefits to heart health of sunlight will outweigh the risk of skin cancer. We now plan to look at the relative risks of heart disease and skin cancer in people who have received different amounts of sun exposure. If this confirms that sunlight reduces the death rate from all causes, we will need to reconsider our advice on sun exposure."

Bonnie: What's even better is that dermatologists cannot just say "take vitamin D supplements in place of the sun," because the nitric oxide pathway craves sunshine as well!

No comments: