Learn more about lipids with Professor Thomas M. Terry. Fats or triglycerides are formed by three fatty acids each bonded by an ester linkage to glycerol. 1  Twist and turn the lipid below to see how kinky fatty acids are.
Superficial peels are the mildest type of chemical peel. They can be used on all skin types. In most cases, they use liquid containing a mild (dilute) acid, most often glycolic acid. Dry ice (solid carbon dioxide) is sometimes used. Medium peels soak deeper into the skin than superficial peels do.
There is a wide range of chemical peels and they peel to different depths: very superficial, superficial, moderate, and deep. 1  The depth of the peel is determined by three factors: how acidic it is (also known as the ph), the percentage or strength of the peel (20% glycolic vs 70% glycolic) and how long it stays on the skin.