The skin''s natural color is the result of a mixture of four vital dyes

1- Oxygenated hemoglobin (red color) in the artery blood.

2- Non-oxygenated hemoglobin (blue color) in the blood of a vein.

3- Carotide (yellow color) in the subcutaneous adipose tissue and the horny layer of skin complexion and from food as an external source, especially vegetables and fruits such as carrots.

4- Melanin (brown color) in the basal layer of the skin''s skin.

This is considered the skin content of melanin is the primary determinant of the color of the skin, so the greater the content, the darker the skin color (dark skin).

The skin color is mainly determined (white - brown - black) depending on two important factors:

The first: the genetic factor, which is called the basic melanin synthesis.

Second: The inducer factor resulting from the sun''s ultraviolet rays, which is called induction melanin pigmentation.

According to this induction factor and the intensity of it, more melanin is produced, and accordingly the skin patterns are divided into six patterns depending on the ability of the skin to take the bronze color after exposure to the sun, as the first pattern

(Very white) Never takes a bronze color, but always burns after exposure to the sun, unlike the fourth pattern (wheaty skin).

There are two mechanisms for increasing melanin in the skin

The first mechanism: increasing the number of melanin-secreting melanocytes.

The second mechanism: increasing the secretion of melanin without increasing the number of melanin-secreting melanocytes (melasma).

There are two levels of pigmentation by depth.

Vitiligo disease

The diagnosis of vitiligo is usually through a clinical examination and x-ray, and may resort to taking a skin sample to confirm the diagnosis.

As for the treatment of vitiligo, it depends on the extent and duration of vitiligo in the skin and ranges from creams to medications to the use of ultraviolet rays specifically (B).

Hormonal causes: the most important of which is a deficiency of thyroid hormone.

Genetic causes: phenol ketoneuria: a recessive genetic disease that leads to mental retardation and the absence of color in the skin and hairs.

4 - inflammatory causes: the most important of which is leprosy - pityriasis versa.

5- Chemical causes: phenol - hydroquinone.

6- The following causes of skin infections: psoriasis, eczema, white scaling, scleroderma.

albinism

Genetic disease caused by a genetic defect. Clinically, he pretends that there is no pigmentation in the skin, hair follicles and eyes, specifically the iris and retina, so the skin appears white or pink in color, transparent iris, and the retina without pigmentation, and this is what makes patients suffer from blurring of vision, nystagmus, and sometimes around the eye and fear of light.

The causes of hyperpigmentation cases are many, the most important of which are

1- Hormonal causes: Addison''s disease - Cushing''s disease (a defect in the secretion of the adrenal gland hormone).

۲- Genetic causes: Freckles - neurofibromatosis.

۳- Metabolic causes: hepatic cirrhosis - chronic renal insufficiency.

4- Dietary causes: malnutrition - digestive malabsorption - pellagra disease (nicotine acid deficiency) - hypercarotene.

5- The following causes of skin infections: Eczema - flat lichen - amyloidosis - sclerosis.

6- Medicinal reasons: estrogens - psychological refreshments.