This is in response to the following comment left on the post Stop buttering your body:
Yes, it is true that the sun is a primary source of vitamin D, but it is not the only source or necessarily the ideal source. The downside to ultraviolet light on skin has been documented with hundreds, likely thousands of studies over the years. The detremental effect of UV light on unprotected skin is dramatic, even if it is not immediately obvious. To state that people should avoid sunscreens altogether is just plain bad advice. It is true that certain sunscreen ingredients can cause an increase in free radicals in the skin, but the resulting damage to the body from this is FAR LESS than the result of any UV exposure on unprotected skin. The way to prevent this increase in free radical production is to use a stable sunscreen formulation and reapply at least every two hours of sun exposure. Also, topical antioxidants, such as added to a suncreen, are a great way to prevent this.
Thank you for taking your time to write. I surely would not argue that vitamin D is available to us from a variety of sources. I have to wonder why, however, we are able to make it ourselves if it isn’t an ideal source. Research demonstrates repeatedly that a few minutes of sunshine is good for us in many ways. Vitamin D formation is one of them. I favor exposure to sunlight. Some people are overly sensitive and they need to moderate their exposure times. That does not mean that everyone needs to block the sun’s rays with a chemical.
The effects of appropriate amounts of UV light are beneficial. Excess sunlight – as with excesses of everything – can be harmful. There is no doubt that sunburns can be as lethal as any other burn. Over the decades, consumers have come to BELIEVE that sun blockers are safe and effective. This misplaced belief is cause for many people to extend exposure times well beyond safe limits. In addition, topical protection is easily washed away, leaving the customer exposed to harsh rays – for periods beyond safety. Modern advertising tries to convince consumers that newer products are less likely to wash off. There is no solid evidence to support that kind of marketing hype. Sweat and water wash the creams away. Recommendations to reapply fall mostly on deaf ears. The false belief persists that the lotions provide protection – in a safe manner.
Can you provide information about the stable sunscreen formulation you mention? I’d like to know what process or ingredient would stop the conversion of sun blocking chemicals to free radicals. Also, I am not aware of research that demonstrates how any topically applied antioxidant can counteract the free radicals formed on the skin. The UV rays are powerful and bring about significant chemical changes. I would imagine that the lotion makers would have already discovered the correct combination of blocking chemicals and antioxidants. They would be trumpeting their success. I hear not a note about this.
Harm from sunlight is directly related to excess. Slathering on a chemical-rich lotion seems inappropriate given the potentials for harms from free radicals that you agree about. I conclude that it is far better to limit exposure and use real coverings to protect from excess (hats, clothing, roof, etc.). I think it is sad that it has become so easy to look for another chemical or drug to counteract the effects of one that has been used. I’d prefer to avoid the side-effect in the first place. Users can be harmed by chemicals in sun blockers. There is not a single report of anyone getting cancer, for example, by wearing a long sleeve shirt and slacks. It is not necessary to bare our bodies to excessive amounts of damaging rays. Yes, we may want to do it, but there are no health reasons to do so. Enough is always enough.
I stand firm in my opposition to the use of topical sun blocking products. It is unhealthy to use them when there are other – SAFE – options.