The Benefits of Sunshine

Government health departments have been warning us about the dangers of sunlight for decades, but new research is starting to change their tune. Even in countries like the UK which get minimal sunshine, people have been told each summer to stay indoors between 11:00 am and 3:00 pm, wear hats and put on lots of sun cream. However, the UK's National Institute for Health and Care Excellence (NICE) has recently changed those recommendations based on studies which prove the benefits of regular exposure to the sun. Sunlight is essential for our bodies to produce vitamin D, which is one of the most important nutrients for good health. Maintaining an optimum level of vitamin D decreases the risks for heart disease, lung problems, infections and several types of cancer. Perhaps even more important these days is it’s ability to fight Covid-19. Many studies have shown that people with high levels of vitamin D are much less likely to have serious illness if they get Covid. 


The original reason for the warnings about sunshine were based on the fact that overexposure to the sun can cause higher rates of skin cancer. NICE acknowledges this risk, particularly for certain skin types, but having weighed all the evidence they concluded that sunlight is mostly beneficial as long as people don't get sunburned. Their latest guidelines specifically warn against cancer scare tactics saying that: “A skin cancer prevention campaign should also mention the risk of underexposure”. Julia Pakpoor, a vitamin D researcher at the University of Oxford, and Michael Holick of Boston University (US), join other scientists in praising the efforts of NICE to keep up with the latest developments. They say that the new guidelines are “an important step in the right direction”.  


Not only is sunlight essential for the body to produce vitamin D, but recent studies have revealed another powerful benefit of getting enough sun. Researchers at Georgetown University (US), have found that sunlight energizes the T-cells that play a central role in human immunity. “We all know that sunlight provides vitamin D, which has an impact on immunity among other things. But what we have discovered is a completely separate role that sunlight plays in boosting immunity,” says the study's senior investigator, professor Gerard Ahern.

The research found that low levels of the blue light found in the sun’s rays make T-cells move faster. “T-cells need to move to do their work, which is to get to the site of an infection and orchestrate a response,” Ahern says. “This study shows that sunlight directly activates key immune cells by increasing their movement.” He added that blue light from the sun, as well as from special lamps, is the safest form of sunlight and does not promote skin cancers. The study concludes that there is still much work to be done to understand the full impact of these findings. However, they suggest that T-cell activation by blue light is completely safe with no side effects, so it makes sense to offer it to patients to boost their immunity.