We may tend to think that getting away from the daily grind is what relaxes us on holiday, but the sun may play a larger role than previously thought.
Researchers at Universities of Southampton and Edinburgh found that exposing skin to sunlight may help to reduce high blood pressure by altering the levels of Nitric Oxide in the skin and blood.
Nitric Oxide, which is found naturally in green leafy vegetables and Beetroot, has a powerful relaxing effect on the blood vessels, which in turn reduces blood pressure.
The researchers found that sunlight was the key to unlocking the skin’s abundant stores of Nitric Oxide, allowing small amounts to enter the blood stream.
Although over-exposure to sunlight can raise the risk of skin cancer, the researchers suggest that the risks are outweighed by the benefits of sunlight in reducing cardio-vascular issues such as high blood pressure.
According to World Health Organisation statistics, high blood pressure accounts for around 30% of all deaths worldwide whereas skin cancer only causes around 0.6% (there were 46,000 skin cancer deaths in 2008).
The research adds to our understanding of why blood pressure rates tend to rise in the winter, and are generally higher in more northerly latitudes.
The study exposed 24 healthy individuals to Ultraviolet A (UVA) radiation in two 20 minute sessions – and found that it significantly lowers blood pressure by altering the Nitric Oxide levels in the bloodstream.
However, it did not change Vitamin D levels, suggesting that it doesn’t play as big a role in the process as previously thought.
Martin Feelisch, Professor of Experimental Medicine and Integrative Biology at the University of Southampton said, “It may be an opportune time to reassess the risks and benefits of sunlight for human health and to take a fresh look at current public health advice. Avoiding excess sunlight exposure is critical to prevent skin cancer, but not being exposed to it at all, out of fear or as a result of a certain lifestyle, could increase the risk of cardiovascular disease”.
Of course, while a holiday or two can certainly help, there are plenty of causes of high blood pressure, many of which can be changed with small behavioural and lifestyle changes to help you keep your blood pressure down all year round.