Sunlight lowers blood pressure
23 January 2014 09:45
Exposing skin to sunlight may help to protect against high blood pressure and the consequences that come with it
Catching some rays could help to reduce blood pressure and so cut the risk of heart attack and stroke, it is claimed.
Researchers from the Universities of Southampton and Edinburgh have found that exposing skin to sunlight can be beneficial in terms of health, meaning all those days of topping up our tans on our travels could prove to be time well spent.
They analysed the skin of 24 healthy individuals by exposing them to ultraviolet (UVA) light from tanning lamps for two sessions of 20 minutes each.
The volunteers were exposed to both the UVA rays and the heat of the lamps in the first session, while in the second session the UV rays were blocked so that only the heat of the lamps affected the skin.
UVA exposure was shown to dilate blood vessels, significantly lower blood pressure, and alter nitric oxide metabolite levels in the circulation, all without changing vitamin D levels.
"Nitric oxide, along with its breakdown products, known to be abundant in skin, is involved in the regulation of blood pressure," explained Martin Feelisch, professor of experimental medicine and integrative biology at the University of Southampton.
"When exposed to sunlight, small amounts of nitric oxide are transferred from the skin to the circulation, lowering blood vessel tone; as blood pressure drops, so does the risk of heart attack and stroke."
Limiting sunlight exposure is important to prevent skin cancer, although the authors of the study, including Dr Richard Weller of the University of Edinburgh, suggest that minimising exposure may actually be disadvantageous by increasing the risk of prevalent conditions related to cardiovascular disease.
Cardiovascular disease, which is often associated with high blood pressure, accounts for 30% of deaths globally each year.
Blood pressure and cardiovascular disease are known to vary according to season and latitude, with higher levels observed in winter and in countries further from the equator where ultraviolet radiation from the sun is lower. It is important to remember while booking holidays to take out relevant
The results of the study are published in the Journal of Investigative Dermatology.