‘Skin Whitening’ and ‘skin lightening’ refer to the use of chemical substances or other procedures to lighten skin tone or provide an even skin complexion by reducing the concentration of melanin. Several chemicals are effective in skin whitening, but some have questionable safety profiles.
Skin whitening agents work in two ways
By absorbing the UV rays, thus preventing the sun from darkening skin.
By reducing the production of melanin, the skin pigment found in skin which is responsible for skin darkening.
Most skin whiteners currently in the market contain ingredients like hydroquinone, ascorbic acid[Vitamin C], kojic acid, arbutin, azelaic acid that act as inhibitors of tyrosinase, the enzyme involved in melanin production.
Hydroquinone is a topical agent for inhibiting melanin production. It has potent antioxidant abilities. Some concerns about hydroquinone’s safety on skin have been expressed, but the research, for topical application, indicates adverse reactions are minor and a result of using extremely high concentrations. It is sold in the United States as an over-the-counter drug, but with a concentration of hydroquinone not exceeding 2 percent.
Vitamin C can play important role in the health of skin. Vitamin C regenerates vitamin E and enables vitamin E to provide sustained antioxidant protection in the skin’s elastin fibers. Vitamin C plays a vital role in skin repair. When your skin is injured, its Vitamin C content is used up rapidly in the scavenging of free radicals, and in synthesizing collagen to speed healing.
Kojic acid is a by-product in the fermentation process of malting rice for use in the manufacturing of Sake, the Japanese rice wine. Some research shows kojic acid to be effective in inhibiting melanin production. However, kojic acid is an unstable ingredient in cosmetic formulations. Upon exposure to air or sunlight it can turn brown and lose its efficacy.
Arbutin is derived from the leaves of bearberry, cranberry, mulberry or blueberry shrubs, and also is present in most types of pears. Arbutin has three properties; Whitening effects, anti- ageing effect and UV filter.
Azelaic acid is a component of grains, such as wheat, rye, and barley. It is applied topically in a cream formulation. Azelaic acid is used to treat acne, but there also is research showing it to be effective for skin discolorations
Licorice inhibits tyrosinase activity of melanocytes.
Many treatments use a combination of topical lotions or gels containing melanin-inhibiting ingredients along with a sunscreen, and a prescription retinoid.
Depending on your skin, chemical peels and lasers may be used.
Lactic acid and glycolic acid peels allow effective penetration into the top layers of skin. It is believed that their benefit is in helping cell turnover rate and removing unhealthy or abnormal superficial skin cells (exfoliation) where hyper pigmented cells can accumulate. However, some research has shown that lactic and glycolic acids can inhibit melanin production other than their action as an exfoliant on skin.
Niacinamide and Glutathione also have skin lightening properties.
Q-Switched NdYag laser [Helios II] has been shown to provide excellent results in improving skin tone & lightening of skin by direct action on melanocytes.
CO2 fractional laser [UltraPulse Lumenis] gives excellent results, although downtime may be 4-5 days