Human skin color varies from different hues of brown to pink. The pigment which determines the skin color of each individual is called melanin. The skin color evolved primarily to protect the skin from the harmful UV rays. People who live near the equator with high exposure to UV rays have more melanin pigments for protection. Hence they are dark-skinned. People who live closer to the poles with less UV exposure have fewer melanin pigments and are light-skinned.
Changes in skin color can happen due to various reasons. Changes in skin tone because of tanning or scars are considered normal. Other changes which require medical advice are regarded as skin abnormality.
Tanning is caused when the skin is exposed to excessive sun rays. The body tends to produce more melanin for UV protection. The area exposed to sun rays becomes darker than the rest of the body, resulting in an uneven skin tone. Tanning is not exactly a skin condition or abnormality. Covering the exposed areas or using sunscreen can protect one from the UV rays. But overexposure to UV rays can cause sunburns, skin aging, and even skin cancer.
Scars are a form of tissue called fibrous, which replaces the normal skin after an injury. Simple scars from small wounds, acne, itchy insect bites can fade away in weeks. Any other major wound or surgery can cause permanent scars. Even though the skin looks different from the rest of the body, scarring is considered as a natural part of the healing process. There are some treatments available as well to remove the scars.
Hyperpigmentation is caused because of the overproduction of melanin, but it is not only because of exposure to UV rays. Hyperpigmentation can be because of the various following reasons. Pregnancy can be one of the main reasons for hyperpigmentation. The skin is darkened around the neck and at the lower part of the stomach, which eventually goes away after the child’s birth. The decrease in the function of the adrenal gland can cause hyperpigmentation. The use of certain medications is one of the reasons for hyperpigmentation. Skin inflammation, fungal infection, accumulation of iron in the body, exposure to mercury, and smoking are the other reasons for hyperpigmentation.
Acanthosis Nigricans is a type of hyperpigmentation caused by hormonal imbalance. It results in the occurrence of dark patches on the neck, underarms, and knuckles. The dark patch is nothing but extra skin cells produced by the imbalanced hormones regulating the blood sugar level called insulin. Sedentary lifestyle, junk food, lack of exercise, obesity, diabetics, and polycystic ovary syndrome are the causes of Acanthosis Nigricans.
These dark patches are often mistaken as dirt accumulation. Irrespective of regular cleaning and scrubbing, these patches won’t fade away. Doctor consultation is a must to treat this condition. Proper medication, along with healthy food and lifestyle changes, can help to overcome the condition.