Hyperpigmentation of the skin can cause uneven color and dark patches. Excessive production of melanin is responsible for this condition.
Hyperpigmentation can occur on almost any part of the body, including the face, neck, hands, arms and legs. The root cause of pigmentation is generally attributed to internal factors like hormonal changes in the body, pregnancy and various health problems. External factors like excessive sun exposure, skin injury, burning, emotional stress or contact with certain chemicals can also cause hyperpigmentation.