Should We All Run From the Sun?

By Julie Rawe

Short answer: Not entirely. Excessive exposure to ultraviolet (UV) radiation causes skin cancer, premature aging and cataracts, but a little sunshine helps keep bones strong. Here's a look at where fun in the sun gets a bit shady:

Don't people need regular sun exposure to get enough vitamin D?

Yes. The body uses UV light to make vitamin D, which is vital for bone health, but the fair-skinned need only a few minutes of summer-sun exposure on the face and forearms and can get their winter D from fortified milk or vitamins.

Is indoor tanning any safer than sunbathing?

No. UV lamps come with all the health risks of natural sunlight, according to the American Academy of Dermatology. They emit some vitamin-D-- inducing UVB rays, which in excess cause sunburns and skin cancer, and many more UVA rays, which cause wrinkles and can lead to skin cancer.

How much protection does sunscreen offer?

A lot, when used properly. That entails slathering on a shot glass's worth every two hours, regardless of whether the lotion is touted as waterproof, sweatproof or has a high SPF (sun-protection factor). SPF refers to the ability to deflect burning UVB rays (SPF 15 deflects 93% of them; SPF 30 blocks 97%), but it says nothing about protection from UVA rays, which are just as harmful. The Food and Drug Administration has not yet approved a UVA rating system but has approved some ingredients that protect against UVA rays. Look for broad-spectrum sunscreens that contain Parsol 1789, zinc oxide, titanium dioxide or the newly approved Mexoryl. And reapply often, even on cloudy days.

Does a so-called base tan protect against sunburn?

For fair-skinned people, a base tan is the equivalent of SPF 4, which translates into a little extra time in the sun before they start to burn. The larger issue, says the Skin Cancer Foundation, is that any change in skin color is a sign of UV-radiation damage, so building a base tan should be regarded as destructive rather than protective.

Are spray-on tans and sunless tanning lotions safe?

Yes. Many dermatologists are recommending them to patients who want to look tan. The active ingredient, dihydroxyacetone, affects only the outermost layer of skin and fades with exfoliation. One cautionary note: because these products tend to provide little UV protection, they should be used in conjunction with sunscreen.

Do people with naturally dark skin have to worry about sun protection?

Yes. The melanin in black and brown skin offers only partial protection from UV rays, not unlike a base tan. Although melanoma is far more common among whites, it is more likely to be fatal among blacks and Hispanics because the cancer develops undetected longer. One of the most famous people to die from melanoma: Bob Marley.