The body is constantly rebuilding itself.  Old cells die and are replaced by new, healthy cells.  The skin renews itself from the bottom to the top.  New skin cells are formed in the bottom layer of the epidermis and migrate to the surface where they eventually die and fall off.  As we age, the time between when they die and actually fall off increases.  The build up of dead skin cells on the surface of the skin makes it look dull and dry and prevents the penetration of any skin renewing topical formulas.   New skin cells will not be made at the bottom of the epidermis until the dead ones at the top are shed. 

Exfoliation is the process whereby we help the skin get rid of the dead skin cells so that it can make new cells quicker.  It can be done mechanically, enzymatically, or chemically.

Mechanical exfoliation products are also called “scrubs”.  They contain small granules which are manually moved across the skin surface.  Dead cells are basically scraped off with physical friction.  Though effective, scrubs can be damaging if not chosen carefully and used correctly.  If the granules they contain are jagged rather than spherical, they will cause microscopic cuts on the skin’s surface.  I personally think that scrubs are much too harsh for aging or sensitive skin.  Remember, do no harm!

Enzymatic exfoliation uses proteolytic enzymes (usually from papaya or pineapple) to breakdown dead skin cells.  It is recommended for those with sensitive skin that can’t tolerate friction or rubbing.  I prefer this method of exfoliation over the others for mature skin.

Chemical exfoliation employs Hydroxy Acids to dissolve or loosen the glue-like substance that holds dead cells together.  It too, is a very effective method but may leave the skin red, irritated, and sensitive to light.  Unlike the other methods of exfoliation, the dead cells are not shed immediately.  They flake off over a period of days giving the skin a very dry, flaky appearance.