The terms skin whitening, skin lightening, and skin bleaching cover a variety of cosmetic methods used in an attempt to whiten or lighten the skin.
Skin lightening or whitening is a controversial topic as it is closely intertwined with the detrimental effects on health, identity, self image, racial supremacy and colonial mentality.[1][2] There is evidence to suggest that some types of skin-whitening products use active ingredients (such as mercurous chloride) and hydroquinone which can be harmful.[3] Hydroquinone has now been banned in Europe and in many other countries can only be prescribed by a doctor for certain skin conditions. There are skin lightening formulas which do not contain chemicals harmful to skin and are safe to use.[4] These are more likely to be manufactured in countries where there are strict regulations governing the cosmetics industry, as in the UK, Europe and USA.
There is a growing market in skin lightening products that are toxic free which have the drawback of being more costly due their expensive ingredients. One of the first to be introduced was the European brand Super Skin Lightener. Japan and the Pacific is a big market for high quality skin lightening products imported from Europe.[5]In India, Fair and Lovely by Unilever remains a popular brand despite the company being forced to withdraw television advertisements for the product in 2007.
In developing countries, banned chemicals are still being used in skin lightening creams.
Topical treatments
Topical hydroquinone is considered by many dermatologists to be a safer, similarly effective (if not more so), and less expensive option than lasers or deep peel treatments. Topical hydroquinone comes in 2% (available in cosmetics) to 4% (or more) concentrations (available from a physician or by prescription), alone or in combination with tretinoin 0.05% to 0.1%. Research has shown hydroquinone and tretinoin to be powerful tools against sun- or hormone-induced melasma.[9]
Hydroquinone has been shown to cause leukemia in mice and other animals. The European Union banned it from cosmetics in 2001, but it shows up in bootleg creams in the developing world. It is sold in the United States as an over-the-counter drug, but with a concentration of hydroquinone not exceeding 2 percent. [10]
Some research has shown topical azelaic acid in 15% to 20% concentrations to be as efficacious as hydroquinone with a decreased risk of irritation. Tretinoin by itself has also been shown to be useful in treating hyperpigmentation of sun-damaged skin. Kojic acid, alone or in combination with glycolic acid or hydroquinone, also has shown good results due to its inhibitory action on tyrosinase (though kojic acid has had problems in terms of stability and potential negative effects on the skin and is rarely used today). Several plant extracts and vitamin C also have some research showing them to be effective for inhibiting melanin production.[11]
Niacinamide is claimed to be a much safer alternative when applied topically for skin or genitalia whitening.[citation needed] According to a cosmetic company, it has no adverse side-effects and as well as acne reduction, also increases skin moisture and reduces fine wrinkles. [12]
Home made treatments
Many people the world over use home made treatments for a whiter skin, rather than buy commercial skin lighteners. These home made treatments include extracts of lemon juice, milk, lime, liqorice and other herbs.[13]
Mercury
Many skin whiteners contain toxic mercury such as mercury(II) chloride or ammoniated mercury as the active ingredient. However mercury has been banned in most countries (Europe 1976)(USA 1990) for use in skin whitening because it accumulates on skin and it can have the opposite results in the long term. Some studies suggest that long-term use could cause systemic absorption that leads to tissue accumulation of the substance.[14]
Hydroquinone
In medical literature, hydroquinone is considered the primary topical ingredient for inhibiting melanin production.[15] Its components have potent antioxidant abilities.[16]
Hydroquinone is a strong inhibitor of melanin production, meaning that it prevents skin from making the substance responsible for skin color.[17] Hydroquinone does not bleach the skin but lightens it, and can only disrupt the synthesis and production of melanin hyperpigmentation. It has been banned in some countries (e.g. France) because of fears of a cancer risk.
Some concerns about hydroquinone's safety on skin have been expressed, but the research when it comes to topical application indicates negative reactions are minor or a result of using extremely high concentrations or from other skin-lightening agents such as glucocorticoids or mercury iodine. This is particularly true in Africa where adulterated skin lightening products are commonplace.[18]
Because of hydroquinone's action on the skin, it can be irritant, particularly in higher concentrations of 4% or greater and predictably when combined with tretinoin. Some medications have been created that combine 4% hydroquinone with tretinoin and a form of cortisone. The cortisone is included as an anti-inflammatory. The negative side effect of repeated application of cortisone is countered by the positive effect of the tretinoin so that it does not cause thinning of skin and damage to collagen.[19] The EU has now outlawed sales of lightening products containing hydroqinone. Safer alternatives are more expensive but are available.
Alternatives to hydroquinone
Some of alternative lighteners are natural sources of hydroquinone. They include Mitracarpus scaber extract, Uva ursi (bearberry) extract, Morus bombycis (mulberry), Morus alba (white mulberry), and Broussonetia papyrifera (paper mulberry). All of these contain arbutin (technically known as hydroquinone-beta-D-glucoside), which can inhibit melanin production. Pure forms of arbutin are considered more potent for affecting skin lightening (alpha-arbutin, beta-arbutin, and deoxy-arbutin). Beta-Arbutin is also known by its more common name of Bearberry extract
Other options with some amount of research regarding their potential skin lightening abilities are licorice extract (specifically glabridin), azelaic acid, and stabilized vitamin C (L-ascorbic acid, ascorbic acid, and magnesium ascorbyl phosphate).
There is also a small amount of research showing oral supplements of pomegranate extract, ellagic acid, vitamin E, and ferulic acid can inhibit melanin production.[20]
Arbutin
Arbutin is derived from the leaves of bearberry, cranberry, mulberry or blueberry shrubs, and also is present in most types of pears. It can have melanin-inhibiting properties.[21]. Arbutin and other plant extracts are considered safe alternatives to commonly used depigmenting agents to make the skin fairer. Medical studies have shown the efficiency of Arbutin for skin lightening.[22] There are patents controlling its use for skin lightening. Skin creams like Super Skin Lightener contain arbutin with a combination of ingredients to lighten skin.
Tretinoin
Research has shown that the use of Tretinoin (also known as all-trans retinoic acid) can only be somewhat effective in treating skin discolorations.[23]
Users of tretinoin have to avoid sunlight, as the skin can tan. Using tretinoin makes the skin more sensitive to UVA and UVB rays.
Alpha hydroxy acids
Alpha hydroxy acids (AHAs) — primarily in the form of lactic acid and glycolic acid — are the most researched forms of AHAs because they have a molecular size that allows effective penetration into the top layers of skin. It is generally assumed that in and of themselves AHAs in concentrations of 4% to 15% are not effective for inhibiting melanin production and will not lighten skin discolorations in that manner. It is believed that their benefit is in helping cell turnover rates and removing unhealthy or abnormal layers of superficial skin cells (exfoliation) where hyperpigmented cells can accumulate. However, other research has shown that lactic and glycolic acids can indeed inhibit melanin production separate from their actions as an exfoliant on skin.[24]
Alpha hydroxy acid peels (using 50% concentrations or greater) may remove skin discolorations. Only a qualified physician should perform these types of facial peels.[25]
Kojic acid
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 for inhibiting melanin production.[26] However, kojic acid is an unstable ingredient in cosmetic formulations. Upon exposure to air or sunlight it can turn brown and lose its efficacy. Many cosmetic companies use kojic dipalmitate as an alternative because it is more stable in formulations. However, there is no research showing kojic dipalmitate to be as effective as kojic acid, although is it a good antioxidant. Further, some controversial research has suggested that kojic acid may have carcinogenic properties in large doses. [1] [27]
Azelaic acid
Azelaic acid is a component of grains, such as wheat, rye, and barley. It is applied topically in a cream formulation at a 20% concentration. Azelaic acid is used to treat acne, but there also is research showing it to be effective for skin discolorations.[28] Other research also indicates azelaic acid may be an option for inhibiting melanin production.[29]
Vitamin C
Magnesium ascorbyl phosphate, L-ascorbic acid, ascorbyl glucosamine, and ascorbic acid are various forms of vitamin C considered stable and effective antioxidants for skin.[citation needed] There are very few studies showing them to have benefit for inhibiting melanin production. The concentrations of these ingredients used in tests were generally high (more than 5%), which is rarely used in cosmetic formulations.[30]. Vitamin C can help brighten the skin tone.
Depigmenting agents
Most commonly, depigmentation of the skin is linked to people born with vitiligo, which produces differing areas of light and dark skin. These individuals, if they so decided to use a lightening process to even out their skin tone, could apply a topical cream containing the organic compound monobenzone to lessen the remaining pigment. Monobenzone may cause destruction of melanocytes and permanent depigmentation. An alternate method of lightening is to use the chemical mequinol over an extended period of time. Increasingly, people who are not afflicted with the vitiligo experiment with lower concentrations of monobenzone creams in the hope of lightening their skin tone evenly. However, monobenzone is not recommended for skin conditions other than vitiligo.
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