1. Health

Sun Exposure and Your Health

Myths and the Truths About Exposure to and Protection From the Sun


Updated May 11, 2012

Myth #1: All exposure to the sun is dangerous.

Myth #2: Most of us need total protection from the sun to stay healthy and younger looking.

Myth #3: Only light-skinned people are at risk of developing skin cancer from sun exposure.

Myth #4: When it comes to avoiding skin cancer, the best protection is to use sunscreen or sunblock.

Myth #5: When it comes to using sunscreen to avoid skin cancer or to keep wrinkles at bay, you can get twice as much protection from an SPF 30 product as you do from an SPF 15 sunscreen.


If you think there's a typo or some other mistake above, then like most of us, you don't really understand the risks and benefits to sun exposure. When we don't truly understand those risks and benefits, we may create problems for our health over the long run.

So here is some basic information about sun exposure, and how you can protect yourself while you enjoy spending time in the sun.

Here's what we need to know about the sun and radiation:

The sun emits three types of ultra-violet (UV) radiation, two of which are considered dangerous to humans (the third never reaches the earth.)

  • UVA rays cause most skin cancers, and the wrinkles and age spots we see on skin that is age related - called photoaging. They penetrate everything that might get in their way: the ozone layer, clouds, trees and clothing, and the top layers of human skin. They are dangerous to everyone, no matter how dark their skin.

  • UVB rays also penetrate human skin, causing health problems (described below) when we have been overexposed.

    The difference between UVA and UVB rays is that UVB rays don't always reach through the earth's ozone layer - they may be blocked before they reach human skin.

  • UVC rays never reach the earth's surface, so we don't need to be concerned about skin damage from them.

Here's what we need to know about exposure to the sun:

As humans, we use Vitamin D to help keep our bones strong. One source of Vitamin D comes from exposure to the sun, although no more than 5 to 30 minutes of sun is needed to get the Vitamin D benefit from the sun. (It should be noted that the American Association of Dermatologists has taken the stand that Vitamin D should be obtained from nutritional sources, and not from direct exposure to the sun.)

Exposure to sunlight (not necessarily sun radiation) may be necessary for our mental health. Seasonal Affective Disorder (SAD) describes a mild form of depression (sometimes called "winter blues") that in some studies has shown to be improved, or even cured, by exposure to bright light, like sunlight. In this case, the exposure needed is not direct, so concerns about too much exposure would not apply.

Too much exposure, any more direct exposure to the sun beyond those 5 to 30 minutes mentioned above, can cause relatively minor health problems (sunburn, sun poisoning) in the short term. But extra exposure without protection from the sun's rays may add up to major health problems in the form of skin cancer later in life. If you were one of those kids who got a bad sunburn at the beginning of every summer, or are covered in freckles and don't tan easily, you may also have a genetic propensity to be damaged by the sun that makes that extra exposure an even bigger risk. Even if you have darker skin, you can still develop skin cancer from exposure to the sun.

Too much radiation from the sun can also cause eye problems like cataracts, and, according to the FDA, may also impact your immunity - your ability to fight off disease.

We also need to be aware that even when we don't see the sun shining, on a cloudy or even a rainy or snowy day, the sun is still present, and the UVA rays can still penetrate them to overexpose us. Granted, we may not turn red or appear to be burned as we might on a non-cloudy day, but unless we protect our skin from the sun, even when we can't see it, we can still put our future health at risk.

There are four ways to protect ourselves from overexposure to direct radiation and the burning the sun can cause:

  1. Don't go outdoors.
    ...Which is impractical for most of us.

  2. Cover ourselves completely with sun-barrier clothing when we go outdoors.
    ...Which might work sometimes, but won't work if our intent is to work outdoors, exercise, play sports or, of course, go swimming. At a minimum, our hands are exposed.

  3. Stay out of the sun when we're outdoors, in the shade, perhaps under a tree or some sort of covered area.
    ...Again, this will be partially effective some of the time, but is impractical much of the time.

  4. Cover our skin with sunscreen to protect areas not covered by clothing.
    ...This is always an option.

Most of us make all four of those choices at one time or another.

But the real problems we have stem from #4 - using sunscreen - because just like those myths about sun exposure listed above, most of us think we understand what we need to know about sunscreen - but we are wrong.

If you love to be outdoors, and know you'll be exposed to the sun, and think you understand what you need to know about sunscreen, think again. Because there was so much confusion, and to regulate the claims made by sunscreen manufacturers, the FDA stepped in, and in 2012, began to require testing, and regulated what could be claimed on sunscreen labels.

Take a few minutes to brush up on Sunscreen 101 - the simple, but very important basics you need to know about sunscreen and its ability to protect you from overexposure to the sun's radiation.


The CDC's Basic Information about Skin Cancer and UV

Sun and sunscreen information from the American Academy of Dermatologists

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