Chemical peels are a form of exfoliation that treat a number of conditions, including dull, aging skin, fine lines and wrinkles, and hyperpigmentation.
Chemical peels work because they are highly acidic, loosening and eradicating dead skin cells. This allows newer and healthier skin to rise to the surface.
There is a wide range of chemical peels and they peel to different depths; very superficial, moderate, and deep.
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.
Examples of very superficial or gentle peels include a 20% glycolic or a 25% lactic acid peel. The most aggressive "superficial" peel is a Jessner's which is not offered in most spas. Moderate to deep peels can reach into the dermis, or living part of the skin.
Deep peels are limited to phenol peels, the strongest of the chemical solutions. While it has the potential to have the most dramatic results, there are more risks, and you need to be prepared for a week to ten days of downtime as new skin forms.
No matter what the depth of the chemical peel, it is important to protect your skin from the sun afterward.