Some advice to bear in mind when selecting sunscreen:

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■ Look for products with an SPF of 15 to 50, and that are labeled “broad spectrum protection,” meaning they protect against both UVA and UVB rays. Higher SPF values are misleading. “It’s like the gas mileage sticker on a car. It’s based on test conditions that you’ll never achieve in the real world,” said Ms. Lunder.

■ Keep babies younger than 6 months out of the sun, as their skin is especially sensitive. Sunscreen should not be used on infants. If they are outdoors, keep them completely covered and in the shade.

■ Try to keep older children inside when the sun is harshest, from 10 a.m. to 2 p.m. A bad sunburn in childhood or adolescence doubles the risk of melanoma later in life, according to the Skin Cancer Foundation.

■ Avoid sunscreen sprays. The F.D.A. has banned sunscreen powders (though some products may still be available) and has asked for more data on sprays. The concern is twofold: that not enough sunscreen makes it onto the skin, and that the spray may be inhaled into the lungs.

■ Avoid products with vitamin A, retinol or its derivatives, such as retinyl palmitate and retinyl acetate. At the moment, the F.D.A. says there isn’t enough evidence to suggest these are harmful, but the Canadian health authorities appear to be concerned that the additives increase sun sensitivity. They have proposed requiring that sunscreens with retinyl palmitate carry a warning saying they can increase the possibility of a sunburn for up to a week.

■ The Environmental Working Group recommends avoiding products with oxybenzone, a chemical that may disrupt hormones. Though research has found this effect, many scientists say the effect is so weak as to be insignificant. The advocacy group, however, recommends products that use zinc oxide and titanium dioxide as active ingredients. (These products may leave a milky white film on the skin.)

■ Look for fragrance-free products. Scents bring more unnecessary chemicals and potential allergens to the mix.

■ Take endorsements and seals of approval with a grain of salt. The Skin Cancer Foundation gives a “seal of recommendation” to sunscreens, but only if their manufacturer has donated $10,000 to become a member of the organization.

Source:
Well NY Times Article
Skin Cancer Foundation
How does sunscreen work?

When’s the Last Time You Spent Time in the Sun?

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This is an important question to answer, because vitamin D from sun exposure is the best way to optimize your vitamin D levels and thereby reduce your risk of a wide range of diseases. 

Unfortunately, it’s been suggested that only about 30 percent of Americans’ circulating vitamin D is the product of sunlight exposure, which is an unfortunate byproduct of public health agencies’ misguided advice to stay out of the sun to avoid cancer (when in fact vitamin D from sun exposure will prevent cancer). Another obvious reason is the majority of us work indoors, and when not working, do not spend enough time enjoying outdoor recreation.

Occasional sunlight exposure to your face and hands is insufficient for vitamin D nutrition for most people. To optimize your levels, you need to expose large portions of your skin to the sun, and you may need to do it for more than a few minutes. And, contrary to popular belief, the best time to be in the sun for vitamin D production is actually as near to solar noon as possible. Ultraviolet light from the sun comes in two main wavelengths — UVA and UVB. It’s important for you to understand the difference between them, and your risk factors from each.

First there is UVB, the healthy wavelengths that help your skin produce vitamin D. Then there is UVA, which is generally considered the unhealthy wavelengths because they penetrate your skin more deeply and cause more free radical damage. Not only that, but UVA rays are quite constant during ALL hours of daylight, throughout the entire year — unlike UVB, which are low in morning and evening, and high at midday.

So to use the sun to maximize your vitamin D production and minimize your risk of skin damage, the middle of the day (roughly between 10:00 a.m. and 2:00 p.m.) is the best and safest time. During this UVB-intense period you will need the shortest sun exposure time to produce the most vitamin D.

As far as the optimal length of exposure, you only need enough to have your skin turn the lightest shade of pink. This may only be a few minutes for those who have very pale skin.

Once you have reached this point your body will not make any additional vitamin D and any further exposure will only result in damage to your skin. Most people with fair skin will max out their vitamin D production in just 10-20 minutes, or, again, when their skin starts turning the lightest shade of pink. Some will need less, others more. The darker your skin, the longer exposure you will need to optimize your vitamin D production.  If sun exposure is not an option a vitamin D3 supplement can be taken orally.

Research published by Grassroots Health from the D*Action study shows the average adult needs to take 8,000 IU’s of vitamin D per day in order to elevate their levels above 40 ng/ml, which they believe is the absolute minimum for disease prevention.

Important: Your Serum Level is what Really Matters

While 8,000 IU’s of vitamin D3 per day is a general recommendation that appears to be beneficial for most people, vitamin D experts from around the world are in agreement that the most important factor is your vitamin D serum level. There’s no specific dosage level at which “magic” happens. So the take-home message is that you need to take whatever dosage required to obtain a therapeutic level of vitamin D in your blood.

At the time (in 2007) the recommended level was 40-60 nanograms per milliliter (ng/ml). Since then, the optimal vitamin D level has been raised to 50-70 ng/ml, and when treating cancer or heart disease, as high as 70-100 ng/ml.

 

 

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