Arginine, an amino acid naturally present in our body to synthesize proteins, is a 100% natural cosmetic active ingredient. It is traditionally used to adjust the pH of cosmetics and as a hair conditioner. It is known to strengthen the hair fiber, regenerate damaged or broken hair, and make hair easy to style, supple, soft, and shiny. Valued in hair and phanera care (nails, eyelashes, and eyebrows), it is also widely used in moisturizing treatments (it is included in the list of NMF - Natural Moisturizing Factors - naturally occurring moisturizing agents in the skin).