When your skin is exposed to sunlight, it responds with immediate protection

Out of the sun

Maybe…and it’s still just a maybe…if a doctor were living under a rock with his head actually buried in the sand below, then maybe I could understand his still not knowing that your skin converts sunlight to vitamin D.

Assuming that isn’t the case, then there is no excuse for any M.D. They should all know this key fact about such an important vitamin.

And yet, many doctors still recommend that you put on sunscreen before you go outside. In fact, one doctor told me to apply sunscreen EVERY time I go outside. Even for brief stints. In all seasons.

Um… No. That’s just crazy.

It’s like saying, “Vitamin D? None for me, thanks!”

But it’s also crazy because it’s overkill. Protection from harmful UVB radiation is right there — exactly where you need it most.

Under the boardwalk…

Your skin has a built-in sunscreen. It’s a pigment called melanin. It causes your skin to tan and helps prevent DNA damage.

Your skin cells also contain a light-sensitive receptor. Every time you step into the sunlight, millions of receptors prompt the cells to begin producing melanin.

This remarkable process was recently discovered by Brown University biologists. Less remarkable — and somewhat hard to understand from a scientific standpoint (but not a PR or commercial one) — is the Brown team’s recommendation that people should continue liberal use of sunscreen.

I know they’re being cautious, because they probably don’t know if a layer of sunscreen might subvert melanin’s natural protection. But there’s a lot of evidence that it does.

And there are two more worrisome problems with sunscreen…

1) When you apply it before sun exposure, it may impede vitamin D production

2) Some sunscreens contain a synthetic vitamin A derivative that may increase risk of skin cancer

The Brown discovery actually reinforces HSI recommendations for sun safety.

* Go ahead — expose yourself…

A few minutes of unprotected sunlight exposure prompts the skin to produce vitamin D. This the best way to boost your D levels. And as the Brown study shows, your skin protects itself through this brief period of exposure.

* Then cover up…

You should always avoid extended exposure. That is, enough exposure to begin a sunburn. If you’re going to be outside for a while, take extra precautions. Wear a hat and clothing that covers as much of your skin as possible.

* Use sunscreen sparingly, only as a backup…

If you spend a day at the beach with your kids or grandkids, it’s going to be hard to keep them fully clothed. In that case, the sunscreen you choose should be the least harmful available.

Every year, the Environmental Working Group (an independent non-profit) revises its ratings on the safety of sunscreen products. In a section of the EWG website (ewg.org) called “EWG’s Skin Deep,” you’ll find dozens of product ratings. These ratings can help you choose a sunscreen with the highest protection and the least amount of unnecessary chemicals.

“UVA Phototransduction Drives Early Melanin Synthesis in Human Melanocytes” Current Biology, Vol. 21, No. 22, 11/3/11, cell.com

“Skin ‘sees’ UV light, starts producing pigment” Brown University News & Events, 11/3/11, news.brown.edu

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