Hyperpigmentation of the skin is when a portion of the skin is darker than the other surrounding areas. This occurs due to melanin. Melanin is the pigment that is produced by cells called melanocytes. Melanin gives the skin its color. When the skin produces more melanin, it leads to hyperpigmentation.
Hyperpigmentation is mostly seen in either exposed area, for example, skin of the face. However, areas that are closed off and subject to greater amount of friction also experience hyperpigmentation. These areas include the neck, elbows, knees and the axillae (armpits).
Hyperpigmentation seen in closed areas is mostly due to a skin condition called acanthosis nigricans (AN) where patches of velvety texture that are darker than ideal are seen on the skin.
Other causes of hyperpigmentation of skin include:
The skin needs to be exfoliated to remove the debris and reveal soft, supple skin.
Ultraviolet rays that may damage the skin if overexposure. A good sunscreen with sufficient SPF is essential.
An imbalance of hormones occurs and that can have varying effects on the body, one of them is hyperpigmentation.
The hormone imbalance tends to cause hyperpigmentation in various areas of the body.
Diabetics are more likely to experience hyperpigmentation and acanthosis nigricans. are more likely to suffer from diabetes later in life.
Due to obesity, the skin becomes stretched and can rub against itself more often.
Most women experience these after menopause. However, as a general rule, the skin starts experiencing detrimental changes after the age of 25 years.
Hyperpigmentation is more likely to be seen in those with a darker skin. Africans and Latinos who have darker skin have a greater incidence of hyperpigmentation.
Fungal infections are common in areas of excess friction or where there is more sweat, e.g. the axillary region, beneath the breasts, leg folds, etcetera.
Patients who have pre-existing skin conditions like psoriasis or eczema are more likely to experience hyperpigmentation.
Acne marks or past injuries can cause hyperpigmentation of skin that are quite difficult to get rid of.