The culprit causes the skin to become discolored when exposed to sunlight

Why does the Sunlight darken the skin? The answer is due to melanin.

To better understand, we need to delve into the membranes of the skin. Skin cells and components such as hair follicles, sweat glands and gland glands form the first protective layer of the skin before impact from the external environment.

The skin structure consists of 3 layers: Upper dermis, central dermis and dermis . Each layer has a separate cell structure with different functions.

Dark skin is caused by melanin.

To understand why dark skin is dark when exposed to the sun, we need to focus on the outer layer of the skin: the epidermis.

The epidermis consists of two main types of cells: keratinotyce and melanocyte.

Horn cells form the skin surface and are the first layer to be affected by the environment. Located at the bottom of the class is often melanocytes. These astrocytes are where melanin is produced to protect the skin against ultraviolet rays (UV rays) from the sun.

How is Melanin created?

Inside each melanocyte contains many specialized pigment cells called melanosomes . Chemical reactions occurring inside melanosomes turn amino acids tyrosine into melanin.

When the sun shines on the skin, UV rays can penetrate the body causing DNA damage and can cause skin cancer. At that time, melanocyte cells will enhance the production of melanin and transport them on the keratinocytes. Melanin will cover the nucleus of the cell, forming a protective 'shield'. They absorb ultraviolet rays and prevent them from attacking the DNA inside the cell nucleus.

Therefore, the more the skin is exposed to the sun, the more the body produces melanin and the skin becomes more dull.

Besides melanin, genetic factors also contribute to determining the tanness level of each person.