| UV
radiation
The sun gives off ultraviolet (UV) radiation
that we divide into categories based on
the wavelenght. UVC radiation is absorbed
by the atmosphere and does not cause skin
damage. UVB radiation affects the outer
layer of skin, the epidermis, and is the
primary agent responsible for sunburns.
UVB does not penetrate glass, and the intensity
of UVB radiation depends on the time of
day and the season. UVA radiation penetrates
deeper into the skin and works more efficiently.
The intensity of UVA radiation is more constant
than UVB without the variations during the
day and throughout the year. UVA is also
not filtered by glass.
Sunscreen
ingredients
Sunscreens ingredients can be divided into
compounds that physically block radiation
or compounds that absorb radiation. The
radiation blockers are very effective at
reducing the exposure of the skin to both
UVA and UVB ratiation. A newer formulation
of micronized titanium dioxide provides
excellent protection, and is not as opaque
and noticeable as zinc oxide. The radiation
absorbing ingredients will depend on the
type of radiation the product claims to
be able to absorb-UVA absorbers or UVB absorbers.
Choose
the right sunscreen
The SPF measures the amount of UVB absorption,
but there is no method of reporting the
UVA absorption. The only way to determine
if a sunscreen protects against UVA and
UVB radiation is to look at the ingredients.
A good broad-spectrum sunscreen should have
an SPF of at least 15 and contains avobenzone,
titanium diaxide, or zinc oxide.
Proper
application of sunscreen
People don't put on enough sunscreen to
get the SPF level of protection stated on
the bottle, say New Zealand and English
researches. They suggest a new way of measuring
the right amount of sunscreen-spread a thickness
of 2mg/cm squared per application or a simpler
way is to imaginary divide your hand into
nine squares and just squeeze out the sunscreen
to fill up one of the nine squares. Consumers
typically apply much less than this - between
0.5 and 1.5mg/cm squared, according to studies.
That is only 25% to 50% of the recommended
amount. If it is SPF 15 sunscreen then they'll
only have protection of SPF 7, chances of
getting sun burnt are more likely.
Sunscreen
should be applied generously enough to all
sun-exposed areas that it forms a film when
initially applies. It takes 20-30 minutes
for sunscreen to be absorbed by the skin,
so it should be applied at least a half
an hour before going out in the sun. Sunscreen
should also be the last product applied
especially on the face since some sunscreens
can break down in the presence of water
contained in water-based foundations and
moisturizers. Then it also needs to be reapplied
after swimming, excessive sweating, or towelling.
The daily use of a low-SPF sunscreen (15)
has been shown to be more effective in preventing
skin damage than the intermittent use of
a higher spf sunscreen.
Age-defying
Sunscreens!
Our genetic composites play a small role
in skin aging as well. Our face and hands
age faster than other body parts since they
are constantly unprotected and exposed to
environmental insults, such as the sun.
Each hour spent in the sun ages your skin
by four hours!
You may
want to try SkinCeuticals© Topical
Vitamin C, which is designed to counteract
the effects of sunlight atmospheric pollutants
and aging. With antioxidant properties,
it helps fight free radical damage, provides
ultraviolet immunosupression and provides
ultraviolet photoprotection, resulting in
smoother and brighter-looking skin.
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