Sun tanning causes skin to darken as a result of excessive exposure to UV rays. Exposure to sun causes secretion of vitamin D and excessive exposure can cause skin cancer. It can also cause reduced immune system functions and premature aging of skin. Melanogenesis means production of melanocytes by melanin. Melanin protects our body from overexposure to the atmosphere. As it absorbs solar radiation, it causes DNA damage. In the process of protecting the skin, further melanin is released which causes skin to darken.
There are two types of tanning:
- UVA :Ultraviolet A has a range of 320 to 400 nm and is not blocked by the ozone layer. It causes release of melanin from melanocytes to create a tan colour. UVA can be carcinogenic and cause DNA damage too.
- UVB :UVB has a wavelength of 280 mm to 320 nm. UVB causes direct DNA damage because this is not blocked by the ozone layer. It accelerates excessive production of melanin resulting in tanning.
Chemical Peels are the best way to combat tanning. They are refreshing and can treat most ailments of the skin aesthetically. The TCA peel is very helpful in repairing sun damage. TCA comprises of Trichloroacetic Acid. This is a light peel which improves skin discolouration and smoothes skin texture. They are considered to work deeper than glycolic acid or lactic acid peels. TCA brightens the skin, evens the skin tone and reduces dark spots and hyperpigmentation. Before administering the TCA peel, it is recommended to use retinoids and stop exfoliants. The skin is cleaned and prep solution is applied. The TCA peel is then applied on the affected surface. After the administration of the peel, some side effects may be noticed such as redness or tightness. Antibiotic creams are prescribed for healing of the skin and it is advised to drink lots of water.