Mayo Clinic: What is better for sun protection: a chemical
sunscreen or a physical sunscreen? Is it really necessary for
me to wear sunscreen even if I work in an office all day?
chemical and physical sunscreens offer effective sun
protection when applied correctly. Physical sunscreens usually
are less expensive than chemical sunscreens. Given that they
also are hypoallergenic, physical sunscreens may be a safer
choice for some people who have sensitive skin. It is a good
idea to wear sunscreen every day even if you work indoors.
protects your skin from the sunís ultraviolet, or UV, light.
There are two types of UV light that can harm your skin: UVA
and UVB. UVA is the long wavelength of light that penetrates
to the deep layers of skin. UVA leads to skin damage over time
that can prematurely age your skin, causing wrinkling and age
spots. UVB is the shorter wavelength of light that penetrates
the surface of the skin and causes sunburn. The best
sunscreens offer protection from all UV light. These are
labeled as "broad-spectrum" or
sunscreen literally blocks UV light from reaching your skin by
either reflecting the light or absorbing it. These products
contain zinc oxide or titanium dioxide. Some people donít
like to use physical sunscreen, because it remains visible on
the skin after you apply it. It also can be hard to wash off.
However, physical sunscreen provides significant, lasting
protection from UVA and UVB light. It also tends to be less
irritating to the skin than chemical sunscreens. That can be
particularly beneficial for younger children and individuals
who have sensitive skin.
sunscreens work by absorbing the UV light and causing it to
undergo a chemical reaction that prevents it from damaging
your skin. Many chemical sunscreens are available.
choose sunscreen, check its sun protection factor, or SPF.
This number gauges how well a sunscreen blocks UVB rays.
Experts agree that an SPF factor of 15 is the minimum needed
to prevent skin damage from UVB. Sunscreens with SPFs higher
than 50 provide only a small increase in UVB protection,
compared to SPF 30 or SPF 50. That means high SPF sunscreens,
such as SPF 100, may not be worth the added expense you pay
for them when compared to the protection they offer.
to getting the full amount of SPF protection from sunscreen is
applying it generously and frequently. Most people simply do
not apply enough. For example, about two tablespoons of
sunscreen, or about enough to fill a shot glass, is only
enough for your face, your neck and the back of your hands.
Apply sunscreen generously to the rest of your exposed skin as
well. Reapply sunscreen at least every two hours, or more
often if youíve been sweating or swimming. A sunscreen may
be water-resistant, but no sunscreen is waterproof.
protect your skin from UV light, wear sunscreen every day,
even if you spend much of your time indoors. For the days you
spend in your office, using a cosmetic product that contains
sunscreen, such as moisturizer or aftershave, is all you need.
When you spend more time outdoors, however, use a stronger
form of sunscreen and reapply it at least every two hours.
mind, too, that you need sunscreen anytime youíre outside,
even if the sun isnít shining. UV light penetrates through
the clouds, and it reflects off water, snow and other
surfaces. When reflected, the rays become stronger, making
sunscreen important year-round.