Why do people have freckles?

The freckles form because the melanin pigment is unevenly distributed under the skin, making the skin darker when exposed to sunlight.

According to Science Alert, freckles are small dots that contain a large amount of melanin, the protein responsible for forming human skin, eyes and hair. Melanin produced by epidermal cells produces melanocytes that help form a protective layer of skin, to prevent harmful UV rays.

Melanin is normally distributed evenly over human skin. But in some cases, melanin concentrated into small clusters, and became darker when exposed to sunlight, forming freckles. Freckles become dimmer when exposed to less sunlight, for example during the winter months.

Melanin is the cause of freckles.(Photo: Health Central).

Especially, we never see a newborn baby with freckles, because their skin has not been exposed to the sun.

According to SciShow, scientists are not quite sure why some people have melanin distributed unevenly on the skin. The cause may be related to the MC1R gene . This gene indicates that certain cells produce proteins involved in melanin production.

MC1R determines the content of two pigments in human skin, hair and eyes: dark brown (created by the type of melanin pigment called eumelanin ), reddish yellow (created by the type of melanin pigment called pheomelanin ).

"If the MC1R gene works normally, your body produces more eumelanin, darkens your hair and skin. But if this gene is abnormal, your body produces more facomelanin, making your skin whiter and blonde. and the freckles that appear on the body, " explained expert Sarah Emerson on the Motherboard page.