Skin marks like moles, freckles and birthmarks are generally caused by melanocytes and blood vessels within the skin. Melanocytes are cells located in the outer layer of the skin – the epidermis. These cells are responsible for producing melanin -- a dark substance to shield the skin from harmful ultraviolet (UV) rays from the sun.
Almost everyone would have moles on their body. These moles are basically made up of melanocytes coming together. The color varies between dark brown, reddish, or blue. Most moles are round in shape, and would usually stay the same. They can stick out from the skin, or lie flat, or have hairs growing from them. Sometimes, moles can change in shape, size, and color.
Freckle is another common form of skin marks. Many people have freckles all over their skin. They are caused by darkened melanocytes. When skin is exposed to a lot of sun, freckles can become darker and more spread out. People with fair skin and light hair are the likely ones to develop freckles. To a lot of people, it is comforting to know that freckles could fade or disappear with age.
Birthmarks, also called hemangiomas, show up early in life. Most birthmarks are caused by a collection of blood vessels in one place. Some might appear as sticking out from the skin, or others might be smooth and lying flat. In most circumstances, birthmarks are harmless. They might even disappear as a person grows older.
Would any of the above skin marks be a cause of concern? Generally speaking, no. However, we need to understand that there are a number of reasons that could turn healthy skin cells into cancerous ones. Once skin cells turn cancerous, they could multiple uncontrollably. The worse scenario is that they could spread to different body systems, and eventually causing death.
Bearing this in mind, it is always prudent to keep a watchful eye on any changes on the condition of your skin marks. If anything looks suspicious, refer to the specialist.