Many cosmetic and pharmaceutical products contain glycerin, accurately metered in products as varied as soap, shaving cream or skincare creams.

Indeed, glycerin is a humectant agent that has the property of retaining several times its weight in water, making it an indispensable moisturizing active ingredient. Its effect depends on the quantity contained in the product: an increase in the glycerine content will improve its moisturizing and protective effect (Gloor 1997).

 Several studies and publications have demonstrated the many benefits of glycerin on the skin:

• Glycerine hydrates the stratum corneum, promoting skin elasticity (Froebe 1990, Fluhr 2003).
• Glycerine repairs the skin barrier: by promoting the synthesis of lipids in the epidermis, it plays an important role in skin repair processes (Fluhr 1999-2008, Bretenritz 2007).
• Glycerine softens the skin (Batt 1986, Fluhr 2008).
• Glycerine protects the skin against external aggressions such as cold, atmospheric dryness, pollution, UV (Peak 1980, Froebe 1990, Short 2007).
• Glycerin regulates the desquamation of the skin and thus preserves the superficial layers of the epidermis (Breternitz 2007, Fluhr 2008).
• Glycerine has anti-microbial (Saegeman 2007) and virucidal effects (Burns 1994, Cameron 2000).

The glycerin found in cosmetics is often synthetic, derived from petroleum derivatives. Its ecological impact is therefore not negligible. Here is one more reason to favor products containing natural glycerin of plant origin as is the case with the Marseille soap Rampal Latour.