SKIN-LIGHTENING COSMETIC INGREDIENTS 51 dermatologist assessment. Also, other skin parameters such as moisturization, texture, barrier integrity, pH, etc, are being evaluated to give picture of skin health after the use of skin-lightening agents. This leads to screening the potentially harmful side effects of hydroquinone-like substances in addition to the high-value claim proposition for the cos- metics industry. With advances in technology in measurement techniques, it is becoming easier to identify the effi cacy of formulations in different skin types. CONCLUSION Research in the area of skin-lightening agents in an expanding fi eld, with new ingre- dients being added to the repertoire with every new discovery. Although tyrosinase inhibition is still the most sought after mechanism skin lightening, newer pathways are being identifi ed. It has been noted that ingredients that interfere with the path- ways affecting melanin synthesis and transfer show promise as depigmenting agents. Persistent research into skin lightening has also led to new mechanisms being discov- ered in recent years. The aspiration for light skin is on an upward curve and can be satisfi ed only when the cosmetic in the bottle fulfi ls the promise of fair skin. A careful and complete investiga- tion of the ingredient on the basis of its effi cacy and tolerance to individuals through clinical trails is essential to ascertain that the product delivers the promise. ACKNOWLEDGMENTS We thank Dr. Yash Kamath for reviewing the manuscript. Thanks are also due to Dr. Usha Ranganathan and Dr. Lakshmi Madhavi for their help in the preparation of the manuscript. REFERENCES (1) E. N. Glenn, Yearning for lightness, Gender & Society, 22(3), 281–302 (2008). (2) P. H. Eric, H. J. Li, R. W. Min, J. Belk, S. Kimura, and S. Bahl, Skin lightening and beauty in four Asian cultures, Adv. Consumer Res., 135, 444–449 (2008). (3) A. Gupta, M. Gover, K. Nouri, and S. Taylor, The treatment of melasma: A review of clinical trials, J. Am. Acad. Dermatol., 55, 1048–1065 (2006). (4) E. Berardesca, M. Ardigò, M. Berardesca, and N. Cameli, Melasma: Current and future treatments, Expert Rev. Dermatol., 3(2), 187–193 (2008). (5) A. E. Reszko, D. Berson, and M. P. Lupo, Cosmeceuticals: Practical applications, Dermatologic Clinics, 27, 401–416 (2009). (6) T. Kono, W. F. Groff, H. Sakurai, M. Takeuchi, T. Yamaki, K. Soejima, and M. Nozaki, Comparison study of intense pulsed light versus a long-pulse pulsed dye laser in the treatment of facial skin rejuve- nation, Ann. Plastic Surg., 59, 479–483 (2007). (7) T. Hakozaki, T. Hirotsugu, M. Kukizo, Y. Sato, and S. Arase, Ultrasound enhanced skin-lightening effect of vitamin C and niacinamide, Skin Res. Technol., 12, 105–113 (2006). (8) B. Green, R. Yu, and E. Van Scott, Clinical and cosmeceutical uses of hydroxyacids, Clinics Dermatol., 27, 495–501 (2009). (9) E. Clark and L. Scerri, Superfi cial and medium-depth chemical peels, Clinics Dermatol., 26, 209–218 (2008). (10) L. Petit and G. E. Pierard, Skin lightening products revisited, Int. J. Cosmet. Sci, 25, 169–181 (2003).

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