Effect of sunlight exposure on mortality

There are also positive effects of sunlight exposure such as vitamin D production in your body. Vitamin D is important for your bones. Vitamin D or other effects of sunlight may also help reduce your risk of developing some cancers and cardiovascular disease.

People of different skin types react to sunlight in different ways. People with darker skin need more exposure to sunlight than people with lighter skin to produce the same amount of vitamin D, and they also have less risk of developing sun-related skin cancer.

What did we do?

We gathered all the available studies that have measured both sunlight exposure and mortality (death) rates. We were interested in the overall number of deaths (by any cause), as well as deaths specifically caused by cardiovascular disease or cancer.

What did we find?

Our findings are mixed. Exposure to sunlight has been reported both to increase and to decrease your risk of dying. Alongside its harmful effect on skin cancer, sunlight may help prevent other types of cancer. However, there were problems in how the studies were done, so we can’t be certain about the findings. From the information available, there is not strong enough evidence to alter sun exposure advice.

Publication details

Parkhouse T, Spiga F, Rhodes LE, Dawson S, Webster KE, Caldwell DM, Higgins JPT. The effects of sunlight exposure on mortality: a systematic review of epidemiological studies [version 1; peer review: awaiting peer review]. NIHR Open Res 2025, 5:51 (https://doi.org/10.3310/nihropenres.13980.1)