Everyone knows that certain actions, even good, well-intentioned ones, sometimes have unintended consequences. This is almost certainly the case with latest scourge of vitamin D deficiency in many industrialized countries around the world. The lack of vitamin D appears to have nothing to do with diet but rather with people’s zealous attempts to avoid UV damage associated with sunlight exposure.
It seems that citizens have taken the “Slip, Slop, Slap” (slip on a shirt, slop on the sunscreen and slap on a hat) to heart since this anti-sun campaign was popular in the 1980’s. But a June 2014 article which outlined the results of a study conducted by Karolinska Institute in Sweden shows that sun avoidance may not only be leading to vitamin D deficiency, it may even be increasing a person’s risk of skin cancer.
It’s an undisputed fact that too much UV exposure can result in skin cells becoming cancerous. But what many people don’t realize is that, ironically, skin cancer can also develop when the body doesn’t get enough vitamin D. Often referred to as “the sunshine vitamin,” vitamin D actually provides the body with natural skin cancer protection.
Vitamin D is available through some food sources. Animal-based foods are one of the best sources of vitamin D, particularly fish and fish oils and eggs. Milk also contains some vitamin D, and commercially-packaged milk often has extra vitamin D added to it, as do some other beverage products, like certain brands of orange juice. If you happen to be vegan, your ability to get vitamin D from food is limited to almost nothing besides mushrooms (but only if they’ve been exposed during growth to UV light) and grain cereals that have been fortified with vitamin D. Overall, very few foods contain it, and those that do may not contain adequate amounts to meet daily human requirements.
However, the very best source of vitamin D is the sun. Not only is it an abundant, readily-available source, it’s also the best type of vitamin D – the D3 for the body. The body is only able to produce this particular variety (D3) from UVB light exposure.
When you avoid the sun and lather on the sunscreen, you inhibit the body’s ability to produce vitamin D3. The Karolinska Institute’s 20-year study has shown that this trend in total sun-avoidance has lead to an epidemic in skin cancer rates as well as other diseases and illnesses associated with vitamin D deficiency. Other studies have even linked it with increased rates of pre-term delivery in pregnant women.
What should the average person take away from this new information? Does this mean that sunbathing is “in” again? Not necessarily, but it does seem to indicate that a little bit of sun exposure isn’t a bad thing, and is actually good for you.
Just how much sun exposure is safe and necessary for adequate vitamin D production? This is where the numbers get hard to pin down, because it varies greatly from individual to individual. It depends on numerous factors, including a person’s weight, height and age as well as location on the planet. (Those living closer to the equator experience more intense sunlight rays and therefore need less exposure than those furthest from the equator to produce the same amount of vitamin D.) Skin type also plays a crucial role; those with fair skin make vitamin D faster and more efficiently than those with darker skin. Since fair-skinned people burn faster than those with dark skin, they need (and can only tolerate) less sun exposure that those with darker skin tones. According to Dr. Oz, about 10-15 minutes per day of sun exposure (with about 40 percent of your skin exposed- about the equivalent of a short-sleeved shirt and shorts) is probably sufficient for those with fair skin, while those with darker skin should strive for two to three times that amount of sun exposure.
Vitamin D deficiency isn’t the only problem that is linked to prolific sunscreen use. In our next blog we’ll talk about another little-known dirty secret about sunscreen and its potential for creating health problems.
*1 “Compelling evidence: Slathering on toxic sunscreen and avoiding the sun could jeopardize your health and shorten your life.” Natural News. http://www.naturalnews.com/045854_sunscreens_toxic_chemicals_cancer_risk.html
*2 “Safer Sunscreen.” Dr. Victoria Maizes. The Doctor Oz Show (Online). http://www.doctoroz.com/blog/victoria-maizes-md/safer-sunscreen