The principle of skin tanning is the reason why the skin is tanned.

In the hot summer, even the most beautiful girl will get tanned easily if she stays outdoors for a long time. Are you very curious about the principle of tanning? Why does the skin get tanned? Now let us explore the reasons why skin tans.

How skin tans

The main reason for skin tanning is that the skin is exposed to the outdoors for a long time and absorbs a large amount of ultraviolet rays. Ultraviolet rays will stimulate the melanocytes at the base of the skin to become active quickly, shuttle through the epidermal cells, and then move the melanin protein layer by layer through cell metabolism and transfer it to the keratinocytes. The more melanin protein is transferred to the keratinocytes, the darker the skin color. After 2-3 days of activity and sedimentation metabolism, the skin turns from white to red, and from red to black.

It is easier to get a tan when swimming

Have you noticed that if you often go swimming outdoors or exercise at the beach for a day, you will get noticeably tanned? Because when we are at the beach or in the swimming pool, we wear relatively less clothes, almost the entire large area of ​​skin is exposed, so the area exposed to ultraviolet rays will be wider. In addition, many people feel that the temperature in the water and the sea is much lower than on land, and the sun’s ultraviolet rays cannot reach them. In fact, water is the same as glass and floor. They all have the principles of refraction and scattering, which can increase the skin's sensitivity to ultraviolet rays, thereby allowing the skin to absorb ultraviolet rays faster.

Choose the right time to swim so your skin doesn't get tanned

If you don't want to get tanned while swimming, it's best to swim in an indoor swimming pool. If you are swimming outdoors, it is recommended to go around 5 pm, because the ultraviolet rays at this time are not so strong, which can reduce the skin's absorption of ultraviolet rays. However, even at this time, it is still recommended to apply some waterproof sunscreen, so that the effect will be better.

Note: Be sure to dry your body as soon as possible after swimming to reduce the refraction reaction of ultraviolet rays.

Why do you get whiter the more you sunbathe?

Some people find it strange that they don't get darker after sunbathing. Some even get whiter. In fact, getting whiter is just an illusion. The more your skin is exposed to the sun, the whiter it becomes because everyone's metabolic mechanism is different. You will find that people whose skin becomes whiter through the sun sweat very easily, especially when they are exposed to the sun, they really sweat like rain. In medicine, this condition is called sweat whitening. When a person's skin is affected by the sun and its metabolism is faster than others, the replacement rate of skin melanin and keratinocytes will naturally be faster. As long as the melanin protein is not deposited by the keratinocytes, tanning will not occur. The reason why a person becomes whiter after being exposed to the sun is because she can metabolize it in time. This principle is the same as why some people cannot gain weight no matter how much they eat.

Choosing the right sunscreen

The skin gets tanned because of insufficient sun protection, and sunscreen is a very critical step. The choice of sunscreen will vary depending on each person's situation. Depending on the situation, if you are indoors and not exposed to strong sunlight and ultraviolet rays, then you can choose an ordinary sunblock with SPF15-20. Because the ultraviolet rays in the room mainly come from the reflection from the isolation windows and floors. If you are indoors and will be exposed to strong sunlight, you should choose a sunscreen with an SPF of around SPF25~30. If you need to be outdoors for a long time, you should choose a professional long-lasting sunscreen with a sun protection index of SPF50. Choose according to each person's situation, so that you can protect your skin from getting tanned.