Moisturizer/humectant

Ingredients with the function of a moisturizer/humectant help attract and retain water in the stratum corneum of the skin, thereby reducing the feeling of tightness, dryness and roughness. According to DermNet, such substances are hydrophilic, that is, "water-loving", and work similarly to the natural moisturizing factors of the skin; these include, for example, glycerin, urea, sorbitol and hyaluronic acid. (dermnetnz.org) Due to this, the skin looks smoother, softer and visually more saturated with moisture, and in formulas for dry and dehydrated skin such components are especially valuable. The American Academy of Dermatology also notes glycerin and urea among the ingredients that help with dry skin. (aad.org)

In hair cosmetics, such substances maintain fiber moisture, make hair softer, more manageable and reduce dryness in length, especially in conditioners, masks and indelible products. They are also important in the texture of the product itself: they help creams, gels and serums feel less "dry", improve skin distribution and can slow down the drying of the formula after application. Typical examples are Glycerin and Urea: the former is often used as a universal moisturizing component, and the latter, in addition to attracting water, can additionally soften roughened skin areas. At the same time, DermNet points out that products with urea and acids sometimes tingle on damaged or irritated skin, so skin sensitivity should always be taken into account. (dermnetnz.org)