Everyone wants clear, radiant and even skin complexion. However, this can be limited by hyperpigmentation with accumulation of melanin. Hyperpigmentation is harmless and usually occur in areas of the body like face and arms usually exposed to sun. Other causes of Hyperpigmentation are age spots, acne, melasma, and other skin diseases. Hyperpigmentation varies for different people depending on race and genetics.
Who even coined the word bleaching? Bleaching as relates to the skin has been used interchangeably with some other words like depigmentation, whitening, lightening, brightening and it is when substances are applied on the skin or physical treatments are made on the skin in order to lighten the skin colour of a person. However, these words are not the same. Skin whitening can also be used in place of bleaching and it is when the skin colour is lightened beyond the natural complexion while skin lightening is meant to reduce hyperpigmentation and even out skin colour.
Alot of lightening products work to reduce melanin. The melanin content of the skin varies in different individuals based on race. Reducing the melanin content has been found to lighten skin colour. Melanin is a substance released by the body that is responsible for skin or hair colour and two types exist which are eumelanin (black and brown) or pheomelanin (red and yellow). The colour of the skin is dependent to a large extent on the amount of melanin and to a lesser extent is dependent on the skin thickness, amount of carotenoids and amount of blood in the blood vessels.
Agents that lighten or bleach the skin work by reducing the amount of melanin in the skin. This can be achieved through destruction of melanin producing cells, direct destruction of melanin, inhibition of the enzyme that activates the process of melanin synthesis or preventing the transfer of produced melanin to the upper layer of epithelium for it to be expressed. Skin with little or no melanin is lighter than skin with plenty melanin.
Medically, depigmentation or bleaching may come in useful for certain conditions. It may be done on small zones (less than 6cm in widest diameter) or larger zones in the body. Specific zones of dark skin such as seen in moles and birthmarks may be depigmented to match the surrounding skin. In cases of a skin disorder known as vitiligo, unaffected skin may be bleached to achieve a more uniform appearance.
Various agents with different mechanisms of action exist. Hydroquinone prevents the synthesis of melanin and comes usually in 2% in cosmetic formulations. Natural sources of hydroquinone can be obtained from arbutin in mulberry, cranberry and bearberry extracts. These natural sources are considered safer alternatives to synthetic whitening agents. Although pure forms of arbutin now exist which is believed to be more effective than the natural extracts of bearberry, cranberry and mulberry. Kojic acid is a natural byproduct of fermentation of malt rice. Another skin lightening agent is glutathione. Glutathione as well as its lightening effect also is an antioxidant and protects the skin from UV rays. Alpha hydroxy acids (AHA) like lactic acid and glycolic acid can whiten the skin by removing unhealthy, hyperpigmented skin cells from superficial skin layer leading to exfoliation.
Corticosteroids have been used to lighten the skin but have hazardous side effects and only advised to be used under medical professional recommendation.
Monobenzone cause destruction of melanocytes which can lead to permanent depigmentation. People afflicted with the medical condition known as vitiligo can apply topical creams containing monobenzone to even out their skin colour. Monobenzone is an organic compound and many people not afflicted by vitiligo are increasingly using it to whiten their complexion. A chemical alternative to monobenzone is mequinol. Other agents that have been identified as depigmenting agents includes licorice root extract, vitamin E, ferulic acid, azelaic acid, citrus extracts, oral pomegranate and turmeric extract.
Some of these agents are dangerous to the body. Hydroquinone is banned in certain countries due to the bothersome exogenous ochronosis it can cause especially in Africans. Other fears are liver damage and skin cancer. There is also the worry of skin irritations such as itching, rash, burning, peeling of the skin, redness and dryness. Mercury has also been banned in several countries because it can accumulate in the skin and leading to toxicities. Effects of mercury poisoning includes kidney damage, nephrotic syndrome, anxiety, depression, peripheral neuropathy, decreased ability of the skin to fight infections, skin scarring, discolourations and rashes. Some also increase the sensitivity of the skin to UV rays. UV rays are known to cause cancer. Bleached skin looses its ability to heal. Some can thin the skin and damage collagen. Other reactions maybe skin irritations, allergic contact dermatitis.
Skin whitening may also be achieved with other methods other than the use of depigmenting agents such as laser treatments. Laser treatments usually produce inconsistent results and usually causes problems for black skin. Cryosurgery uses liquid nitrogen to cause a controlled destruction of skin cells with a resultant regeneration of new skin. With the use of liquid nitrogen, melanin moves to the surface and peels off over a few days. However, it can cause scarification.
Skin bleaching or whitening is hazardous to the body and not recommended. It is only recommended to be done with the aid and guide of medical professionals under certain conditions. When products are bought over the counter, ensure that it does not contain Mercury, corticosteroids and hydroquinone. Many effective, natural products exist and are available for use.