There’s a new, as yet not formally published, study that has generated quite a bit of excitement online and in health circles.

The study is somewhat complicated, but the main finding that has people talking is that ultraviolet light exposure reduces all-cause mortality. This is despite the fact that those with the greatest UV exposure have a higher risk of skin cancer and related mortality. The study found that reduced death rates from other health conditions, and even other forms of cancer far exceeded the increased skin cancer deaths.

While this is a large study, there is controversy regarding the methods used. And while there are numerous other studies that reached similar conclusions about the health benefits of UV exposure, numerous other studies found the opposite – that higher UV exposure increased all cause mortality.

One of the biggest issues is that researchers sometimes look at all sources of UV as being equivalent. But getting UV exposure from sunlight is a very different thing than getting it from an artificial source, such as a tanning bed. Sunlight is not composed of primarily UV – it also has the full visible spectrum, plus infrared (IR), which has been found to have health benefits of its own.

Studies with negative findings on UV exposure often were using either artificial sources (that are primarily UV without significant amounts of other wavelengths of light and IR) and/or were looking at overexposure that resulted in burning and acute skin damage. Generally-speaking, the risks of heavy exposure to artificial UV light outweigh the benefits, and tanning bed use in particular is discouraged.

Sun exposure in which burning is avoided likely has numerous health benefits and minimal skin cancer risks. UV light is needed for the production of natural Vitamin D, which is important for bone health, immune function, muscle and nerve function, and for regulating cell growth (which helps reduce the risk of many cancers).

One does not need to risk burning to get adequate sun exposure to provide good Vitamin D production. A few minutes of sun exposure daily is usually adequate, and although sunscreens do somewhat reduce UV exposure of the skin and resultant Vitamin D production, the reduction is usually not sufficient to cause Vitamin D deficiency by itself under most circumstances.

Chemical sunscreens could potentially have toxic effects in some cases, but the risks are probably far outweighed by the benefit of avoiding severe sunburn, particularly over a period of years. Barrier sunscreens, such as those with zinc or titanium oxide have little risk of toxicity and protect against burning, although they can be more difficult to apply evenly than chemical sunscreens.

Beyond the UV/Vitamin D issue, natural sunlight also provides IR rays, which have benefits of their own, such as anti-inflammatory effects, pain reduction, and improved cardiovascular and circulatory health. There are some concerns regarding IR and skin aging with frequent exposure. Barrier sunscreens can protect against these effects, but simple antioxidants like vitamin C and E (orally as well as topically) will help mitigate these effects without blocking the IR and its potential benefits.

Finally, the visible light in sunlight is helpful in reducing depression and other mood disorders. Regular exposure to sunlight or artificial full-spectrum light can help normalize sleep cycles as well as improving mood and feelings of well-being.

So, while the debate rages over the risks versus benefits of UV exposure, it is becoming more and more clear that the benefits of non-burning sun exposure considerably outweigh the risks. Taking precautions like using sunscreen and clothing to prevent overexposure and burning are strongly recommended, but avoiding sun exposure altogether probably does more harm than good in most cases.

Until next time…

George F. Best, D.C.