Want to cut your blood pressure?
Posted on May 9, 2013, Thursday
Sunlight could lower blood pressure and help stop heart attacks and strokes, scientists claim, a Daily Mail report says.
They argue the health benefits of the sun’s rays outweigh the risks from skin cancer.
Edinburgh University researchers found when skin is exposed to sunlight for just 20 minutes, blood vessels release an important chemical called nitric oxide.
This acts to lower blood pressure, reducing the risk of heart attacks, strokes or blood clots.
Dr Richard Weller, a senior lecturer in dermatology, pointed out that strokes and heart attacks cause many times more deaths than skin cancer.
Around 159,000 Britons a year die from the circulatory illnesses, while skin cancer kills 2,750.
His team monitored the blood pressure of 24 volunteers who sat under tanning lamps for two sessions of 20 minutes each.
In the first session volunteers were exposed to both UV rays and heat. But for the second session researchers blocked the UV rays, exposing them to heat alone.
The volunteers’ blood pressure dropped significantly after the first session, but not the second. This implies it is UV radiation, not heat, which is responsible for the beneficial effects.
The researchers believe sunlight unlocks nitric oxide stored in skin and widens arteries. Both effects lower blood pressure.
Dr Weller will present his findings on Friday at the International Investigative Dermatology conference in Edinburgh.
He said: ‘We suspect the benefits to heart health of sunlight will outweigh the risk of skin cancer.’
He said scientists have known for years peoples’ blood pressure is lower in summer than winter.
Additionally, research shows populations of countries far from the equator, with less sunlight, have higher blood pressure.
Dr Weller said it was not a ‘cure’ and it was ‘too early to say’ if people should go in the sun more.
While the preliminary research involved only a few people, it will fuel the debate over whether sun exposure is good or bad.