How to protect your skin from the sun?
Sunscreen products are effective for protect your skin of sun raysThey must be applied regularly and extensively. Of course, clothing, wide-brimmed hats and sunglasses are essential protection, especially between 11am and 3pm (the period when the sun's rays are most aggressive), but they must be combined with sun protection adapted to the situation and to your phototype.
The phototype classifies individuals according to their physical characteristics et leur niveau de risque face à l’exposition solaire, comme le montre l’illustration ci-dessous :
Some people and some situations present more risks to skin health than others: we are all unequal to the sun. Thus, blondes and redheads produce a particular melanin (pheomelanin) which does not effectively protect the skin. As a result, these phototypes present a major risk of skin cancers. Only a very high level of sun protection can be recommended on exposed areas.
What is the difference between filters and sunscreens?
Sun protection products are effective if they are anti-UVA and UVB. There are protective products on the market that contain sunscreens.
The sun filters used in certain products penetrate the surface of the epidermis and absorb UV radiation for a given wavelength. The sunscreen productsAs for them, they remain on the surface of the skin and reflect white light for a given wavelength as well.
How to find your way through the sun protection indexes?
The protection index is measured differently for UVA and UVB radiation :
Protection against UVB For UVB, the SPF (Solar Protection Factor). This index is measured on the skin of volunteers on the back. The time taken for redness to appear on a small area of skin not protected by a sun protection product and on a protected area, after exposure to an artificial UVB source, is measured.
CLEAR: An SPF 30 rating for a sunscreen product means that it takes 30 times more UVB (i.e. 30 times longer exposure) to cause a sunburn on the protected area than on the unprotected area, regardless of phototype.
UVA protection To know the UVA protection index, it is more complicated because UVA does not make the skin redden. We therefore use other measurement techniques.
In practice, the SPF is written on the tubes of sun protection products. The logo opposite is added if the value obtained for the UVA index measurement is at least one third of the SPF value.
How to properly apply your sun protection product?
- Apply sun protection a quarter of an hour before the exhibitionIn sufficient quantity ("more like two layers than one!").
- Do not forget the ears, neck, nose, hands and feet.
- Use recent products (beware of expiry dates), seal them well after use and keep them in the shade.
- Renew the application every 2 hours or so, or after swimming or excessive sweating.