Pigmentary complaints cause the uneven darkening of an area of skin. This can appear as brown/age spots which can go on to form keratoses (a scaly growth), and pre-cancerous or cancerous lesions. These conditions are difficult to treat because they affect each of us differently depending on our skin type, and how deep in the skin the pigmentation sits. This often depends on the cause of the issue, which is frequently a combination of factors.
Melanocytes in our skin produce melanin as a defence mechanism against radiation caused by the sun. The melanin travels to the surface of the skin to absorb the harmful UV rays. This is the process that, over time, gives us a tan, but within the skin the melanin protects other skin cells, and their DNA, from damage – although this protection is not enough with ongoing exposure to the sun.
Not only does radiation directly damage cells in our skin, it causes excessive Reactive Oxygen Species (ROS) to be produced. ROS cause additional harm to healthy cells and protein, and stimulate melanocytes. Our natural defences against these ROS decline as we age, so their effects are more prevalent in mature skin.
There are several other factors that can also stimulate excessive production of melanin:
- Hormones can have a significant impact on melanocytes, for example while taking the contraceptive pill or during pregnancy. This disruption can cause a condition called melasma, in which excessive pigmentation appears on the forehead, cheeks and around the mouth.
- Inflammation or trauma of the skin can also disrupt the melanocytes and cause increases in ROS. This can be associated with acne, folliculitis or laser therapy.
Although pigmentary disorders commonly effect darker skin types (due to their increased levels of melanin), aged skin can become susceptible to some of the factors described above.