[noun] Exfoliation entails removing, through use of exfoliating agent, the dead cells on the surface of the epidermis. Exfoliation has multiple benefits: it promotes cell renewal, cleans the pores, smooths skin texture and restores the complexion’s natural radiance. There are three types of exfoliation:

• Mechanical (or physical) exfoliation: these are scrubbing mixtures containing granules that can be either synthetic or natural, such as sugar or sand. For such exfoliation to be effective, the scrub must be rubbed over skin surface, causing the granules or grains to loosen and remove the dead skin cells. The granules may be of varying size, with finer grains being more suitable for use on the face and larger granules for body exfoliation. Mechanical exfoliation can also be accomplished using certain accessories, such as cleansing brushes with nubs or bristles suited to face or body use.

The next two categories of exfoliation are known as “grainless” and both work through chemical reactions on the skin. They do, however, have several distinct differences:

• Enzymatic exfoliation: here, the exfoliating agents are enzymes, chemically proteins, sourced from fruit. Technically, they act as a catalyst or accelerator to more quickly dissolve the proteins of dead cells so as to stimulate desquamation (shedding or removal of the stratum corneum). The action of enzymes, compared to that of acids, is lighter, gentler and progressive, as it acts selectively, working only on dead cells. Papain (from papaya) is the enzyme selected for use in the formulation of certain myBlend products, particularly in the range of cleansers for gentle daily exfoliation.
• Chemical exfoliation with acids: in this case, the exfoliating agents are acids (synthetic or natural), which also dissolve the bonds holding the dead cells to the skin’s surface, making them easier to eliminate. Acids penetrate more deeply and can act on cells as far down as the secondary layers of the epidermis to promote cell renewal.
  The best-known acids are AHAs – alpha hydroxy acids (like glycolic acid) – and BHAs – beta hydroxy acids (like salicylic acid). The maximum concentration thresholds differ for acid-containing products and, above a certain concentration, they are reserved for use by medical professionals only.