There are many different dark spots that can appear on the skin. Melanin is responsible for the colour that we see on our skin, including pigmentation spots, but different dark spots have different triggers. Some of the most common pigmentation spots and their triggers are:

• Hyperpigmentation due to exposure to UV rays (also known as age spots): When stimulated by UV rays, the normal activity of the skin's internal cells (melanoctyes) becomes hyperactive, triggering tyrosinase activity and the overproduction of melanin pigmentation. As a result, over time skin forms these dark spots.
• Hyperpigmentation as a result of scarring, contact dermatitis or other irritation: Various forms of irritation can lead to dark spots such as over-cleansing the skin, atopic dermatitis or even blemishes.
• Melasma or Chlorasma: Appears symmetrically on the upper lip, cheekbones and the lower chin in women over 20. The general understanding is that it is triggered by hormonal changes and is exacerbated by UV exposure. There is also a type that occurs only during pregnancy or when taking birth control pills and some other medications that impact hormones. In this latter case the discolouration will usually disappear once the pregnancy is over or the person stops taking the medication.
• Hereditary Freckles: These little spots are inborn and start appearing around the age of 3, and most prominently around puberty. After the 30s, they remain more or less the same or become a little lighter. Their relationship to UV rays is still unknown. People with fair skin, red hair, blond hair or blue eyes are more prone to them.