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Sun's Rays
Things you need to know
The more you know about the harm the sun can do to your skin and facts about
the sun protection, the easier it is to make a smart decision concerning your
health.
The sun is dangerous to your skin. The sun's ultraviolet (UV) rays
penetrate unprotected skin and are absorbed by skin cells, starting a sequence
of reactions. Within five minutes on a sunny day, your skin may absorb
enough UV radiation to develop a slight sunburn. Skin cells may also start
the process leading to a suntan, the skin's natural defense mechanism. In
even less time, skin cells may suffer injury that you cannot see or feel.
Your skin has a memory. Over the years, the damage from daily
overexposure may turn into long-term sun injury, including skin cancer and
sun-induced skin aging. Some damage is triggered by small, daily doses of
sun, other damage by intense, infrequent doses.
For a medically sun sensitive person, the reaction may be more severe and
immediate. And the long-term results, even more threatening.
The dangers of UVA and UVB
There are two types of ultraviolet rays from the sun that hit the earth's
surface- UVA and UVB. Both can cause short- and long-term sun injury,
including sun-induced skin aging and skin cancers.
During the summer, the sun's UVB rays are most intense from 10 a.m. to 4
p.m., while UVA rays are more stable from sunrise to sundown. On a sunny
summer day, there are more than enough UVB and UVA rays to damage your skin.
Sun sensitive people need all-day, broad-spectrum UVA and UVB protection.
The sun protection factor
SPF stands for Sun Protection Factor, a sunburn protection rating. It
is a ration of the time needed to produce a minimal sunburn while using a sun
protective product versus no protection at all. A 30 SPF product allows
you to stay outdoors 30 times longer than you could without sun protection.
It is important to remember that SPF only measures the sunburn rate.
For sun sensitive people, sunburn is just one of the many reactions from
overexposure to the sun.
Although UVA rays are inherently less powerful than UVB rays, 10-100 times
as many UVA rays reach the earth's surface. Small daily doses of UVA can
cause long term injury to your skin, even without signs of sunburn.
Why sunscreen just isn't good enough
Sunscreens are important sun protection because they filter UV rays and,
therefore, can help reduce sun-induced skin injury. They are also far from
perfect. Not only does a typical 30 SPF sunscreen still allow a lot of harmful
UVA radiation through to the skin, published medical studies have shown that
most people initially apply only 1/3 to 1/2 the recommended dose. They
compound the problem by failing to reapply sunscreen regularly and then staying
in the sun longer. Some research shows that UV can cause some sunscreens
to lose their effectiveness beginning in as little as two hours. Other
research shows that sunscreen-slathered beachgoers and triathletes sunburned
after a day in the sun.
Sunscreen alone is insufficient. It is just one sun protection tool
that is part of a sensible lifestyle that includes wearing sun protective
clothing, minimizing sun exposure, and using sunscreen correctly.
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