Tuesday, June 28, 2011
Vitamin D, Sunscreen, and Healthy Skin
Since it’s finally looking like summer outside it seems like a good time to discuss the topic of sunlight and what you should be doing about it. Two popular subjects in the health world are vitamin D and sunscreen, neither of which is very well understood by the general public. After reading today’s post you can stop reading those headlines because the solutions are very simple.
Not really a vitamin, exactly, it’s actually a hormone and is produced by your body. Its effects are so important it’s not even worth mentioning all the pluses. Just know that if you lack vitamin D life is going to get unpleasant very quickly. The good news is that our bodies make it when our skin is exposed to sunlight. You don’t even need very much sun exposure, and your body stores it so it will hang around when the weather turns gray, even for months. Yet numerous studies show many people are drastically low in vitamin D. So what’s the deal?
We’re obviously not getting outside enough but that’s not the entire story because we might be. We’re just using too much sunscreen when we do. Vitamin D is present in very few foods. We can supplement it but we don’t want too much of it because our bodies store it, and too much can be stored (when it can become toxic). Natural exposure is both the safest and most effective way to get it.
It seems that almost everyone now knows that overexposure to sunlight can cause skin cancer and that sunscreen can help prevent it. Unfortunately health officials—and marketing divisions—find it’s easier to sell the public on black and white rather than bother with subtleties like, oh, the fact our bodies needs some sunlight for health and skin cancer, while a very real threat, takes a lot of sun exposure to get. So the powers that inform have been telling us to slather on sunscreen anytime we step out of the house and, apparently, we’ve chosen this one piece of advice (as opposed to “exercise more”, “eat fruits and veggies”, “drink plain water”, “watch less TV” etc) to take to heart, resulting in a widespread problem with vitamin D deficiency.
In fact, so disinterested have these powers been with subtleties that sunscreens have been blocking the wrong rays for years. We’re finally starting for hear about the difference in UVA and UVB rays. Until recently sunscreens only targeted the latter, which incidentally are also the rays we use to make vitamin D. Now it turns out the UVA rays we’ve been letting through can cause skin cancer too, so all our protective measures have not only been leaving us exposed to possible skin cancer but lowering our immune system at the same time. Oops.
Many of the sunscreen companies are now choosing to block UVA rays and inform you about this on their label, but they’re still not too forthcoming about the importance of getting some UVB because, well, it probably doesn’t seem like good business (even though a new study shows vitamin D helps stave off skin cancer). They also don’t tell you that unless you get an awful lot of sun exposure you’re not very likely at all to develop skin cancer or have any damaging effects from the sun at all. The fact is that we not only don’t need, but should not have, sunscreen covering our exposed skin areas all the time.
The simple solution.
The media makes this subject appear complicated but the solution simply is not. We should get outside during the middle of the day on sunny days whenever we can. Not for long; a stroll through the park at lunch on a sunny day is likely plenty of exposure as long as you’re not completely covered up (the AMA recommends 15 minutes of exposure a “few times” per week). You don’t need to be in a bathing suit but wearing shorts and jogging around the park on occasion wouldn’t hurt. We just shouldn’t live like vampires, no matter how cool their lives seem on True Blood.
On the flip side no one needs to lie out at the beach. Fake tanning is still seems like the safest way to mimic an 80s sex symbol. Once you feel your skin get warm you’ve had more exposure than you need. For those of you that do spend a lot of time outdoors, make sure your sunscreen blocks both UVA and UVB rays. And if you’re addicted to sunlight wear a hat. The skin on your face and neck, especially around your eyes, is very susceptible to the raisin effect.
Supplementing vitamin D has been shown to be effective but, unless you never get outside, a base amount is sufficient. Whatever is in your multivitamin is likely fine (The RDAs 400IU is “100%” but not really 100% so don’t worry about it--subject for another day). Also, make sure to try and eat plenty of non-cooked omega 3 and 6s in your diet. These fatty acids protect your skin from sun damage and keep it looking young.
Trying to get too involved in the numbers of this subject will just confuse you. “Nobody really knows how much sunlight you need for optimal vitamin D synthesis versus too much sunlight,” say Jean Tang, dermatologist and lead author of a government study that followed 36,000 women ages 50 to 79 for an average of seven years. And if someone like Tang doesn’t know the math, there’s no reason for you bother with it either.
Further reading and opinions: