Wearing sunscreen should now be part of
our daily routine before we go out. UV rays not only cause skin
cancer, they are also responsible for most of the skin damage
associated with premature aging.
Having become such an important factor
in our lives it is imperative that we know how to choose the best
sunscreen for us. There was a time when choosing a sunscreen was all
about the SPF (Sun Protection Factor). New research and studies have
made it far more complex.
UVB and UVA Rays
There are two types of UV rays: UVB and
UVA. Both types of UV rays cause cellular damage and can cause skin
cancer.
UVB rays are responsible for you
getting a sunburn. SPF refers to this type of UV rays. When choosing
a sunscreen make sure it is at least SPF 15. Active ingredients that
protect against UVB rays are:
- Para-aminobenzoic Acid (PABA)
- Cinoxate
- Ensulizole
- Homosalate
- Octocrylene
- Octinoxate
- Octisalete
- Padimate O
- Trolamine Salicylate
UVA rays penetrate deep into the skin
and cause premature aging such as wrinkles, lax skin and
pigmentation. Sunscreens that protect against UVA rays say “Broad
Spectrum”. Ingredients that protect against UVA rays are:
- Avobenzone
- Ecamsule (Mexoryl SX)
- Meradimate
Ingredients that offer both UVB and UVA
protection are:
- Dioxybenzone
- Oxybenzone
- Sulisobenzone
- Titanium Dioxide
- Zinc Oxide
What SPF should I choose?
The SPF tells us how effective a
sunscreen is in preventing sunburn. If you burn in 10 minutes an SPF
15 will protect you for 150 minutes (10x15) or 2 hours and a half,
SPF 30 for 300 minutes or 5hours. This doesn't mean that you can be
that long without reapplying, remember that rubbing, sweating,
swimming, etc. will decrease its effectiveness.
SPF 15 filters out 93% of UVB rays, SPF
30 filters 97% and SPF 50 filters 98%, so the added protection after
SPF 15 is not much.
Chemical vs Physical Sunscreens
Sunscreens can be further classified
into Chemical or Physical depending on the ingredients they contain.
Chemical sunscreens absorb the UV rays converting them into heat
energy, while physical ones deflect and scatter the UV rays before
they penetrate the skin.
Titanium Dioxide and Zinc Oxide are
physical sunscreens. These are the sunscreens that used to leave a
white film over our skins. New manufacturing methods now break the
molecules into micro-particles that penetrate the skin without
leaving a white residue, beware the cheaper sunscreens may still
leave you looking ghostly.
Physical sunscreens are better because
they are gentler and less likely to cause an allergic reaction. They
are better suited for babies and people with skin conditions such as
eczema, and Rosacea.
Chemical sunscreens have also the
disadvantage that when they absorb the UV rays they break down and
produce free radicals. Free radicals can also damage our cells
accelerating ageing. So, if you can, choose a sunscreen that contains
Titanium Dioxide or Zinc Oxide.
Other factors to consider
When choosing the best sunscreen for
you it is important to consider your skin type. Oily skins
will benefit for a light formula, water based, rather than cream.
Spray on sunscreens may be better for this type of skin. Ensulizole
has a lighter consistency that other UVB filters. If you suffer from
Acne and you are using Retinol or Roaccutane you should
consider that these products make your skin more sensitive to the sun
and take extra precautions, such as using a higher SPF, keeping in
the shade and wearing a wide brimmed hat and long sleeves.
If your skin is dry, some
sunscreens come with added moisturisers which will help maintain your
skin balance.
If you have sensitive skin or
suffer from eczema or Rosacea avoid sunscreens containing PABA
or Oxybenzone as well as fragrances, alcohol and preservatives. The
best sunscreens for sensitive skins are those containing Titanium
Dioxide, Zinc Oxide, Trolamine Salicylate or Ecamsule
For babies and children
it is also best to use a physical sunscreen because they are less
likely to cause any skin reactions. Also, a spray on sunscreen may be
easier to apply, just make sure you don’t spray directly onto their
face, but rather on your hands and then rub it on the face.
How to use sunscreen correctly
Most of us don't know how
to use sunscreen correctly. Here are some tips to make sure you are
well protected at all times:
- Apply liberally. Most people don't apply enough or leave patches uncovered and thus don't get the level of protection stated in the package. It is recommended that you wait 10 minutes and reapply to make sure you have achieved the best coverage.
- Make sure you also apply sunscreen to the back of your neck, nose, tip of your ears, back of your legs, and feet.
- Reapply frequently. Sweating, water, rubbing off with clothing and towels, removes some of the sunscreen, so it is important to reapply every two hours.
- Wait at least 20 minutes before going under the sun. Sunscreen takes that long to be absorbed by the skin.
- If you are swimming or exercising you should buy a water resistant sunscreen. Water resistant sunscreens are good for 40-80 minutes in the water, so you need to reapply often.
- Apply sunscreen even if the day is cloudy or overcast. Remember, UV rays are not visible to the naked eye, and on a cloudy day up to 80% of the UV rays can get through.
- Just because the day is cold it doesn't mean you won't get damage from the sun. You may need less sunscreen during the winter months, but if you are having a day out in the sun, you still need to put on sunscreen.
- Sunscreen is not enough:
- Try to avoid being under the sun between 10am and 4pm.
- Keep to the shade
- Wear a wide brimmed hat
- Wear sunglasses
- Wear long sleeves, and preferably dark clothes with tight woven fabric.
