How Are Age Spots Formed on the Skin?
A patch of skin that appears darker than its surrounding areas is called hyperpigmentation. There are different types of hyperpigmentation. This post is about a type of hyperpigmentation called age spots.
Age spots are flat, and small to medium in size. They are also called liver spots.
Before we get into why age spots are formed, we need to understand the function of 2 types of skin cells called Melanocytes and Keratinocytes.
Melanocytes have long tentacles (like an octopus). They produce melanin. Melanin is like an umbrella for skin - it protects the skin from Sun's UV rays.
Melanin has two colour ranges: brown & black or yellow & red.
90% of the skin is made up of cells called keratinocytes. When the skin is exposed to UV light from the sun, the UV light can penetrate and damage the DNA of the keratinocytes. The immune system kicks in as a response to UV exposure.Here is how the immune system responds:
- Signals melanocytes to generate more melanin
- Melanocytes use their tentacles to transfer the melanin to keratinocytes
- Once they enter keratinocytes, melanin surrounds the nucleus of keratinocytes. The nucleus is where the DNA is
- Melanin forms a shield around the nucleus
- When the UV light attacks keratinocytes, the shield (melanin) now absorbs the UV light
- The more UV exposure, the harder the melanocytes work to generate the additional melanin
This melanin shield is what gives our skin a tan when exposed to the sun. The tan is an immune response. The melanin production stabilises once the UV exposure disappears. Eventually, the tan disappears. But some parts of the skin might end up having deposits of melanin from the overproduction of melanin during the immune response - and these deposits might not go away. These deposits are called age spots. Since melanin has 2 colour ranges (brown & black or yellow & red), age spots also get this colour. There are skin care ingredients called tyrosinase inhibitors that can help in controlling hyperpigmentation.
Melanin cannot protect our skin completely from UV rays. Most protection for our skin is provided by sunscreen. Though the immune system goes into overdrive and produces more melanin, it isn't enough. The best protection we can offer to our skin is sunscreen. Melanin overproduction reduces with sunscreen application. Sunscreen for younger-looking skin. Sunscreen for age spots.