What Determines the Color of the Human Body

The world is full of people with various skin colors, and there are white, yellow, brown, and black skin colors. And there are also individual differences in skin color in the same race, even the different parts of the skin color of one individual at one time are not totally the same. Generally speaking, the skin color of women is lighter than men, and the skin color of young people is lighter than the elderly. According to relative research, the color of human skin is affected by many factors, such as the thickness of the skin layers and the absorption coefficient of the epidermis and dermis. However, there are several factors that determine skin color.

First of all, we should understand that although there are many factors affecting skin color, melanin content is the direct factor that determines skin color. It is not difficult to find that the closer to the equator, the darker the people's skin color is. Because the equator has the most sunlight, where ultraviolet light is also relatively strong. UV rays are very damaging to the skin and can cause skin cancer. However, there is also a protective system in our body, which is melanin. When it comes to melanin, we have to mention tyrosinase, which is an enzyme that affects the activity of melanocytes, and when the skin is exposed to sunlight, tyrosinase will stimulate melanocytes to produce a large amount of melanin, which is used to absorb UV rays and prevent the skin from being damaged by UV rays.

The second is the amounts of various pigments in the skin, such as melanin, carotene, etc. For example, if the number of reduced hemoglobin increases, the skin color will become darker. Nonetheless, the main determinant of skin tone is the amount of melanin in the skin.

Moreover, there are anatomical differences in skin, the thin epidermis easily shows the color of blood in the dermal papillary vessels, the thick epidermis has a poor light transmission and yellowish skin color, such as the palmoplantar skin

Finally, skin color would change, in addition to the above-mentioned several pigment content increase or decrease beyond the normal range, color change can also be caused by the deposition of drugs, metals, foreign bodies, or other metabolic products, but also may be caused by the pathological changes of the skin itself.