The sun and its effects on the skin: we enlighten you!

When the sun comes out, it is difficult to resist the pleasure of outdoor walks and swimming. However, even if they are beneficial for our morale, its rays are not without danger for our health...

But what is their real impact on our skin? Are there differences between the UV ? Questions that you don't necessarily ask yourself when you expose yourself to the sun but whose answers will help you prepare effectively! Here are some basics to know for a summer under high protection.

Sun and radiation: what do you need to know?

Solar radiation refers to the electromagnetic waves emitted by the sun: X-rays and gamma rays, visible light, infrared and ultraviolet. And the shorter the wavelength, the stronger the energy released! Let's forget about X-rays and gamma rays: even if they are extremely dangerous for the body, they are, fortunately for us, stopped by the ozone layer. Let's also look at visible light, which is simply what allows us to see what surrounds us, and infrared, these powerful heat vectors that maintain an average temperature of 17° on the Earth's surface... Let's focus instead on UV !

What are the different types of UV?

UVA: not as harmless as you might think…

They make up 95% of the UV radiation that reaches the planet… and therefore your skin! Less powerful than UVB (their wavelength is longer), but at least 20 times more abundant, they penetrate the epidermis deeply and are known for their effect on skin aging . Because by producing free radicals, which alter the structure of collagen and elastin , they cause wrinkles and pigment spots . But not only that: recent studies show that they also promote the development of certain skin pathologies… So be careful!

UVB: more aggressive than UVA

With an energy 1000 times higher but an average wavelength, they only affect the superficial layers of the epidermis . While they are responsible for a nice long-term tan because they stimulate the production of melanin , they are also responsible for sunburn and most skin cancers.

UVC: the most harmful

But they are completely filtered by the atmosphere and that's good for our health!

Focus on UV index

The UV index: an alert for your health!

Announced in weather reports, this scale, from 1 to 12, was developed by the WHO and is used to measure the intensity of ultraviolet radiation in the atmosphere and the risks to the body. Many factors can influence this index such as the season, cloudiness, latitude or even the state of the ozone layer… But as soon as it is at 3, remember to use sun protection !

How does skin react when exposed?

It triggers its own defense and regulation mechanisms in the form of sunburn… or tanning! UVB rays thus cause a cascade of inflammatory reactions such as redness that appears within 6 hours of exposure. A good signal given by your body! If you protect yourself immediately, cellular damage will be minimal and repaired quickly. Provided, of course, that you do not accumulate sunburns! You would then risk using up your “sun capital”, that is to say, your skin’s ability to protect itself by synthesizing melanins , capable of blocking some of the rays. Your tan is therefore a natural reaction against UV rays. But be careful: it only corresponds to sun protection factor 3 to 5!

focus on the skin

Your skin in summer time

You have probably noticed that its texture changes in the sun: in fact, it thickens to better filter UV rays and protect the cells located between the epidermis and the dermis. It is also more oily because it secretes sweat and sebum which also help to limit the penetration of rays by absorbing and reflecting ultraviolet rays.

Is everyone equal in the face of the sun?

Clearly not: it all depends on your phototype! Defined by the color of your skin, hair, eyes and sensitivity to the sun, it reflects the quantity and nature of melanin produced. Because there are different types. While eumelanins (brown-black in color) are the cause of dark skin, pheomelanins (yellow-red or yellow) are present in people with very light and red skin. More sensitive to the sun, these people have a higher risk of cancer and therefore need stronger protection than dark skin which, thanks to a greater quantity of melanin, naturally filters UV rays... Which does not exempt them from using sunscreen !

Knowing your phototype is therefore essential to adopting the right reflexes when faced with the sun. Understanding the effects of different UV rays helps to better protect yourself from them... To enjoy the summer without sunburn and tan with complete peace of mind!