These methods are based on 3 main points: reducing of dark pigment production, preventing the skin from darkening from the sun, stimulation of the cells renewal and upper cells layers exfoliation. There are numerous kinds of whitening creams, masks and lotions, soaps, gels, chemical peels, lasers, pills etc. developed for skin whitening.
To reduce melanin (dark pigment) production the following ingredients of lightening products are used:
2. Vitamin C
3. Glycyrrhetinic (acidlicorice extract)
4. Kojic acid
5. Retinol (Tretinoin, all-trans retinoic acid)
7. Hydroquinone (hydroquinone products have been shown to have a mild toxic action, but they are still used in some products in low and safe concentrations.)
10. Azelaic acid
These agents inhibit the action of tyrosinase (the enzyme which regulates melanin production) leading to decrease of dark pigment formation.
Exfoliation is another method to achieve skin brightening. The lightening effect of exfoliation depends on the depth of peeling action. Superficial peel can help to remove the outermost dead and dry cells layer, stimulate cells renewal and to speed up the revealing of new fair cells layers. To achieve a visible lightening effect series of superficial treatments needed.
Apart from light peels there are several deep peel methods such as laser resurfacing, cryosurgery, deep chemical peels etc. These techniques allow deeper skin layers and pigmented cells removal causing visible (and sometimes permanent) whitening. Despite of its effectiveness deep exfoliation have some serious risks and side effects like scarring and pigmentation disorders. These peels usually are not recommended to the people with dark and black skin.
The compromise between superficial and invasive deep peels are medium depth exfoliators which can help to achieve visible lightening results with the less risk of injuring and other unwanted effects.
Protecting skin from the taning is onother one important point of skin ligthening. It is necessary to protect the skin from the sun exposure and to use sunscreen cosmetics every day.