The health benefits of sunlight are only now being fully understood…
Extracts taken from full article by Jane Feinmann, inews.co.uk
In 2010, Dr Richard Weller, a dermatologist at the University of Edinburgh, discovered a previously unknown biological pathway by which nitric oxide is stockpiled in our skin and activated by sunlight. Since then, he has shown that exposing volunteers to the equivalent of 30 minutes of summer sunshine without sunscreen both raises nitric oxide levels and significantly reduces blood pressure. Weller’s largest study, reported at the British Association of Dermatologists’ annual meeting in Edinburgh in July 2018, involved tracking the blood pressure of 340,000 people in 2,000 spots around the US for three years, adjusting for variables such as age and skin type. The results have proved conclusively, he claims, that the people in sunnier climates have lower blood pressure than northern neighbours because of higher levels of nitric oxide levels. Separate studies also show that mobilising nitric oxide through sunlight appears to protect against obesity and metabolic disease.
“As a dermatologist,” Weller admits, “I am in the difficult position of trying to balance the undoubted skin cancer-protecting effects of sunscreen against this growing body of evidence showing that exposure to the sun has cardiovascular benefits,” he says. Yet purely as a numbers game, he says there are reasons to go easy on the sunscreen. “Skin cancer kills surprisingly few people compared with heart disease. For every person who dies of skin cancer, more than 100 die from cardiovascular diseases,” he points out. People don’t realise this because several different diseases are lumped together under the term skin cancer. Less well known is the fact that the most common, basal-cell carcinomas, accounting for three in four of the 100,000 cases every year, can be excised relatively simply and are almost never fatal. “People who get basal-cell carcinomas are actually likely to have longer life expectancy because this type of skin cancer is strongly linked to sun exposure and tend to occur in healthy types who are outside getting plenty of sunshine and exercise,” says Weller.
A team, led by Professor Pelle Lindqvist, a senior research fellow in obstetrics and gynaecology, at at Sweden’s Karolinska Institute, showed conclusively that a whole range of health problems are more common in women who avoid the sun – and are also more common in winter. Indeed, when the team checked mortality rate over the 20-year period, they found that sun avoiders were twice as likely to die as sun worshippers, largely due to a greater risk of death from cardiovascular diseases such as heart attacks and strokes. “There are not many daily lifestyle choices that double your risk of dying,” points out Lindqvist. “We found avoidance of sun exposure a risk factor of the same magnitude as smoking in terms of life expectancy,”