A leading Scottish dermatologist has warned the UK’s cautious approach to sunlight exposure could be doing more harm than good – and that moderate time in the sun may bring major health benefits far beyond vitamin D.

Speaking at Scotland’s Health Research and Innovation Conference, the University of Edinburgh’s Professor Richard Weller said the number of deaths prevented by sunlight exposure far outweighs those caused by it.

Findings from his research – part-funded by Scotland’s Chief Scientist Office – suggest that, for every death from skin cancer caused by excess sunlight, 75 deaths from other causes, including cardiovascular disease and cancer, could be prevented.

 

 

Importantly, the study says health benefits of sun exposure are not explained by vitamin D supplementation – rather, other mechanisms such as the release of nitric oxide in the skin may help lower blood pressure and improve cardiovascular health.

Professor Weller said the findings mean current UK public health guidance on sunlight is not fit for purpose.

“At the moment our sunlight advice is based on the historical advice from Australia, which is completely inappropriate,” he told the conference. “The UV [index] in Cairns midwinter is seven for an hour at midday; midsummer, it’s 14. We measured the UV index in Glasgow last year and it hit 7 for just five minutes on one day, just after lunch.

“We need to stop treating all sunlight as dangerous. It’s not just wrong, it’s causing significant health problems for us.”

Professor Weller, who has studied the effects of sunlight on the body for over a decade, presented findings from the UK Biobank involving more than 400,000 people.

 

 

His team compared participants’ sunlight exposure using two measures: behaviour, such as sunbed use and time spent outside, and geography based on the amount of sunlight in different parts of the UK.

The results showed people with greater sunlight exposure lived longer, were less likely to die from cardiovascular disease and cancer, and had overall lower mortality rates than those who got less sun.

 

 

 

 

Professor Weller told the conference sun exposure might partly explain some of the inequalities in life expectancy and health outcomes seen north of the border:

“Every 300 kilometres you move south in the UK, your life expectancy rises by around 16 days.

“Over 12 years, that means people living in London live about a month longer than those in Glasgow – largely due to sunlight exposure.”

He said studies in other northern European countries, including Sweden, have shown similar results, suggesting the effect is consistent across high-latitude populations.