Why do some people get tanned when exposed to the sun, while others get red?

Reviewer of this article: Zhou Xiaobo, Doctor of Medicine, Shanghai Jiao Tong University

It's summer now

The hottest season of the year

This is also when the ultraviolet rays are strongest.

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To protect your skin from damage

I believe that many beautiful ladies

I started paying attention to sun protection early on.

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I don't know if you have such questions.

Some people's skin becomes darker when exposed to the sun

Some people's skin turns red when exposed to the sun.

Why is this?

Come and see

…

turn out to be

There are two types of UV rays that can damage your skin

——

UVA and UVB

UVA is a long wave

Strong penetration

Mainly damages the dermis of the skin

The culprit for sunburn

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UVB ultraviolet rays belong to the medium wave

Mainly damages the skin surface

When this light reaches the surface of the skin

Although it does not have the penetration of UVA to reach the inner part of the skin

But the damage is also very strong

Causes dermal blood vessels to dilate in the irradiated area

This will cause the skin to turn red.

In addition, it will stimulate melanin

Let the skin slowly change from red to brown

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In simple terms

UVA ultraviolet rays will make people darker

UVB will make people more red.

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