How does the sun affect people with dark complexions?
Dark complexions have both advantages and disadvantages when it comes to
sun exposure. On one hand, dark skin is less likely to get sunburned
and less likely to develop skin cancer. On the other hand, because dark
skin naturally provides protection from the sun's ultraviolet rays, it
prevents dark-skinned people from producing the necessary amount of
vitamin D. When people with lighter complexions spend time in the sun, their bodies
produce melanin, the pigment that gives color to skin and creates a
tan. Melanin serves as a natural defense against UV rays, and people
with dark complexions, especially those with olive, brown or black skin,
already have a high concentration of melanin in their skin. This high
concentration of melanin is responsible for their dark complexions and
protects them from burning easily. In fact, as the amount of melanin
increases, so does the natural protection from sunburn. But while a
higher concentration of melanin provides some sun protection, it doesn't
prevent skin cancer.
But everyone needs some sun exposure to produce vitamin D. Vitamin D,
also known as the "sunshine vitamin," helps the body absorb calcium,
which maintains bone density and prevents osteoporosis And research shows that vitamin D may also help protect against chronic
diseases such as diabetes, cancer, rheumatoid arthritis and heart
disease .
However, dark-skinned people's high concentration of melanin makes it
more difficult for them to produce enough vitamin D. In fact, dark
pigment in the skin reduces the skin's ability to synthesize vitamin D
from sunlight by 95 percent. Lighter-skinned people can get enough
vitamin D after 10 to 15 minutes of sun exposure a few times a week, but
people with dark complexions may need five to 10 times more sun
exposure to synthesize that same amount of vitamin D .
Even
though vitamin D is important to your health, you should always wear
sunscreen when spending long periods of time in the sun. If you're
concerned about vitamin D levels, speak to a doctor or dietician. Keep
reading to learn more about how the sun affects people with dark
complexions.
Sunlight
Some
of the sun's rays are beneficial, but others, such as ultraviolet rays,
are hazardous. This radiation comes in three forms: ultraviolet A
(UVA), ultraviolet B (UVB) and ultraviolet C (UVC). The earth's
atmosphere filters out UVC radiation, but UVA and UVB affect you every
day. UVB affects the top layers of skin, while UVA penetrates to the
deeper layers. Your hair and your skin are negatively affected by these
UV rays, although they appear to react differently.
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Melanin
A
pigment called melanin determines the color of your skin and hair. One
form of melanin is a reddish-yellow color, while the other is
brownish-black. The amount of each type of melanin you have in your skin
and hair is genetically determined. Melanin protects your skin from
the sun's harmful ultraviolet A and B rays by turning it a darker color.
People with very little melanin often acquire no tan and are at the
greatest risk for sunburn, premature skin aging and skin cancer. People
with dark skin should also be cautious about sun exposure.
Skin
Your
skin is the largest organ in your body. It protects you from the sun's
harmful rays by producing the pigment melanin to darken your skin.
Ultraviolet rays in sunlight destroy the melanin in your skin, which
triggers your body to produce more and darker melanin. This melanin
reaction to ultraviolet rays can cause sunburn or suntan. UV radiation
also causes the skin to coarsen and wrinkle, making even young skin look
and feel old.
Hair
Most
of the hair on your body is made up of dead cells. Only the root is
living, and once the hair emerges from the skin, the cells die. Melanin
determines the color of your hair. People with very little melanin have
blonde hair, while people with a great deal of melanin have black hair.
Unlike the skin, which can regenerate melanin after UV damage, your
hair is dead and can no longer make melanin. Sunlight kills the melanin
in your hair and fades out the color, making it lighter and lighter.
Your new hair will be as dark as before, since it contains the correct
amount of melanin.
Precautions
Although
light-skinned, light-eyed people are at the greatest risk from UV
radiation, the Skin Cancer Foundation urges everyone to limit their
exposure. Wearing sunscreens, broad-brimmed hats, tightly-woven, loose
clothing and sunglasses helps fend off UV rays. Keeping out of the sun
as much as possible is the best option. This is especially true from
10:00 a.m. to 4:00 p.m. in the Northern Hemisphere.
The American Academy of Dermatologists points out that tanning damages your skin irreparably, especially if you use a tanning bed or sunlamp while in your teens. These devices use the deeply-penetrating UVA rays to turn your skin darker, inuring your skin in the deeper layers. The damage to your skin may not appear until decades later.
The American Academy of Dermatologists points out that tanning damages your skin irreparably, especially if you use a tanning bed or sunlamp while in your teens. These devices use the deeply-penetrating UVA rays to turn your skin darker, inuring your skin in the deeper layers. The damage to your skin may not appear until decades later.
