The spots you are noticing on your skin may be a condition called vitiligo (vit-ill-eye-go). Vitiligo most commonly affects the hands and feet, or around the eyes, ears, and mouth, but may be found all over the body. Although it may simply develop on its own, sun damage can definitely contribute to it. Some doctors even believe that the condition may be an autoimmune disease. This means that the body's defenses against germs are turned against the body itself. In this case, they damage pigment producing cells. A type of skin cells called melanocytes is primarily responsible for producing the pigment melanin, which gives people their color and shields them from sun damage. In vitiligo, however, the melanocytes become damaged and no longer produce any pigment, which is why the skin has white patches. This condition is mainly cosmetic in nature, and therefore harmless, and may be most easily prevented through the use of protective sunscreens. Because the disease leaves unpigmented patches on the skin, the darker the person is, the more noticeable the patches are.
Fairer-skinned individuals hide the spots easily simply by not tanning, but darker people - and especially African-Americans - may have to work a bit more to conceal the spots. In some cases, hiding the patches may be as easy as applying makeup that matches the skin tone. Some dermatologists sell products designed for use on the body skin, as opposed to the cosmetics intended for the face that are sold in stores. For darker people, tattooing over the patches in a color that matches the skin is another option, but the individual is still going to be faced with the problem of pigmented skin changing its color with sun exposure. Actual treatments for vitiligo have not proven to be extremely effective, but some definitely show more promise than others. Doctors may prescribe a topical corticosteroid to counteract the condition. Another option is a time-consuming round of treatment called PUVA, where patients take a pill called psolaren approximately an hour before entering a special tanning box, where they are exposed to ultraviolet light. These visits must take place once or twice per week for at least a year, and are impractical for most people. Perhaps the best place to start is with taking folic acid and vitamin B12 supplements while getting some sun exposure, as several studies have shown that this combination may often reverse the depigmentation associated with vitiligo with very few side effects. No matter how you choose to handle the white spots, be sure to keep in mind that those are patches of skin with absolutely no melanin to protect them from sun burn. It's great that you're using sunscreen that blocks both UVA and UVB radiation, but you might want to consider a higher SPF and pay close attention to covering and protecting those patches.
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