March 27, 2008

Black Skin Tanning

Stupid Question ™
Aug. 13, 1998
By John Ruch
© 1998

Q: Can black people tan?

A: The 23 percent of Columbus, Ohio’s population that already knows the answer first-hand will have to cut me some slack here.

The white naivete may be annoying, but it’s good to counter the dangerous assumption that blacks—and by extension, anyone with dark skin—are sun-proof.

Human skin color primarily comes from a group of pigments collectively called melanin. It’s made in cells called melanocytes and spewed out in packets called melanosomes.

Everybody has the same average number of melanocytes. The wide variation in skin colors—from freckles to deep ebony tones—comes from different shades of melanin and variations in number, size and distribution of melanosomes.

Tanning is melanin’s response to skin damage from ultraviolet light, which at first darkens existing melanin into a temporary tan, then stimulates new melanin to be made for a lasting tan. (Sunburn doesn’t involve melanin—it can appear with or without tanning.)

By the way, there are people who simply don’t tan: Many fair-skinned blonds and redheads have so little melanin they won’t get brown at all—they just burn up. But nearly everybody with dark skin will quickly develop a lasting tan. (While ethnic background determines the amount of melanin you have handy, the degree of tanning still varies from person to person.)
In fact, suntanning can be so pronounced in African-dwelling blacks that their skin color lightens significantly if they move to a more temperate climate.

Tanning is much an idea as a coloration. Fashion maven Coco Chanel popularized it in the 1920s as a symbol of wealth and leisure. And the book “The Color Complex” says that when Marion Barry was running for mayor of Washington, D.C., activists mocked him for being married to a light-skinned black woman—so he sent her to the beach and bought her a sunlamp so she’d look more “black.”

But melanin’s real business seems to be protecting skin cells from UV damage. Studies have shown that naturally black skin is less susceptible to skin cancer and sun-induced wrinkles; it can take as much as 33 times the UV that white skin can before burning. (Tanned skin on Caucasians affords milder protection.)

But it’s simplistic to assume black people were “permanently tanned” by the bright African sun. Black skin’s UV protection still isn’t that great, and may be incidental to some larger function. (Dermatologists say everyone should use sunblock with a Sun Protection Factor of 15 or higher.)

Sunlight’s not all bad. It helps human skin make vitamins, and it may affect the immune system. Human skin color may have evolved to carry out these tasks under different degrees of sunlight. (Pale skin might work better under low light, dark skin under high light.)

Not only can black people tan, they must be tanning—their skin cancer rates are starting to go up.

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