Sunscreen: Proper measures for sunburn (no sunburn)

The baba of a safe tan is to expose yourself gradually, at the right time and during relatively short periods. The mistake is to take the sun at the wrong time and for too long. This has the direct effect of damaging your skin and tan.

• Check the expiry date of your solar

" Products that are too old, that have been opened, that have been in direct sunlight, should not be used any more," warns Dr. Daniel Colleta, PhD in Organic Chemistry. Filters may be diluted or agglomerated in the texture making UV protection ineffective.

• Apply the right dose

Official recommendations are formal: every 2 hours, apply 2mg of product per cm2 of skin. This equates, for an adult to a golf ball. And if you use a solar mist the brands have calculated that it needed 7 pressures for the face and neck and 12 sprays for the rest of the body, front and back.

Also remember to protect the contour of the lips, hands and feet.

• Apply again and again!

A recent study shows that while the majority of people apply sunscreen on arrival on the beach, 75% of them find that enough for the day and do not stand out their tube from their beach bag. But the recommendations of dermatologists are without appeal. You must start to "cream" every two hours, and even more often if you sweat or come out of the water.

• Dry yourself well

The researchers realized that if you applied your sunscreen on wet skin the product lost nearly half of its protection index: "thus SPF 30 milk no longer guarantees protection SPF15 explains Elisa Simonpiétri Director of Scientific Communication Biotherm ". Good news: some solar devices have integrated "Wet Skin" technology. Their formula is hydrophobic, repels water, and leaves a uniform protective film on the skin, contrary to conventional textures that form micro droplets allowing the sun's rays to pass between them.

• Watch your watch

No sunbathing, even well protected under your cream, when the sun is at its peak, that is to say between 12 and 16h (summer time in France).

• Choose the right SPF indices

They depend on your skin type, and the intensity of the sun on your vacation spot. Good to know: in the tropics the rays fall vertically. Sunshine (and protection) maximum. At altitude, UV intensity increases by 4% every 300M. Interesting initiatives of some brands: At La Roche Posay, a UV patch captures UV from the skin. Connected to the smartphone via the My UV Patch application, it controls the UV received during the solar exposure. At Daylong, a UV sensor bracelet changes from yellow to orange when it is necessary to renew the application, and to pink when the maximum dose of sun is reached.

• Choose a photostable filter

Some filters (it's a shame) do not support the light, and in the sun, lose a lot of their photo-protective power. Today the major laboratories have developed molecules that protect the filters. This is the case of Tinosorb® Mexoryl ® etc ... So check the mention "Photostable" when you buy.

• Avoid brutal exposures

Prefer progressive and limited sunbathing. In these conditions, you can easily multiply small exposure times. Moreover, your tan will be more successful and sustainable.