A whiter shade of pale in skin care

In ancient Persia, field workers bleached their skin with pure natural hydroquinone to keep it from darkening under the sun. In Europe, during the Renaissance, lead and mercury compounds applied to the face, neck, and chest, became popular as peel-off skin lighteners. Unknown at the time, many of the earlier lightening ingredients were in fact toxic and this led to their ban for cosmetic use. However, even nowadays, skin lightening remains a popular goal in skin care. A fair skin tone is increasingly associated with a healthy skin and youthful appearance. The field of potential applications for lightening products has grown accordingly to include more specific pigmentation concerns, such as lentigines (dark spots appearing, with older age, on sun-exposed skin), freckles (irregular grouping of pigment-containing cells or melanocytes), melasma (hormonal hyperpigmentation), inflammation-related hyperpigmentation, and even hypopigmentation. Skin lighteners are now perceived as multi-usage cosmetic products although with some geographical and cultural differences. Westerners seek them essentially for their anti-ageing benefits, while Asian people rather use them for general lightening of their skin. With the advancement of science over recent decades, our knowledge of the physiology of skin pigmentation has improved drastically. As we better understand the complex regulation of this physiological process, it is becoming clear that the future of lightening skin care lies in the combination of several actives addressing simultaneously and complementarily the various facets of skin pigmentation. In fact, the trend worldwide is now to offer skin care that combines multiple modulators of pigmentation with anti-ageing actives. This makes sense. After all, factors contributing to skin ageing, such as UV exposure, hormones, oxidation, and inflammatory reactions also affect skin pigmentation, and irregular skin pigmentation is seen increasingly with age. This article will review our current knowledge of the mechanisms involved in skin pigmentation, highlight effective ways of modulating these mechanisms with a combination of selected commercially available actives (see Table 1), and comment the efficacy and safety of a serum (aImage Blanc) integrating this knowledge. The serum described here additionally contains a core anti-ageing technology (REGEN 16) which has already been described elsewhere.1

The cellular and molecular physiology of skin pigmentation

The life of melanin, the main pigment responsible for skin pigmentation, is a fascinating journey. Starting within melanocyte cells with the amino acid tyrosine as the raw material, melanin pigments are assembled in specialised incubators called melanosomes, conveyed to finger-like structures at the tip of melanocytes and then gently transferred to neighbouring keratinocyte cells that rearrange them as protective umbrellas around their DNA. As these pigmented keratinocytes mature, they progress to the edge of the stratum corneum from which they eventually shed through desquamation, leading to pigment loss. Each step of the melanin journey mobilises various enzymes and signalling factors that may turn out to be interesting targets for the modulation of skin pigmentation.