AHA Peeling Concentrate

An AHA peel for skin that looks dull, rough or uneven, made as a leave-on concentrate: you apply it in the evening and leave it on overnight, one or two nights a week. The acid is lactic acid at 10%. It loosens the bonds between dead cells on the surface so they shed more evenly, and it is often chosen as a gentler alternative to glycolic acid.

The formula is short and fragrance free, with nine ingredients: water, 10% lactic acid, pentylene glycol and butylene glycol, glycerin and sodium hyaluronate (hyaluronic acid, 1% according to the product data) to keep skin comfortable, and organic white tea and sage leaf extracts. Potassium hydroxide adjusts the pH.

Apply to clean, dry skin in the evening, avoiding the eye area, and leave it on overnight. Start with one night a week, do not use it on the same night as retinoids or other exfoliants such as the Glycolic Acid Exfoliating Toner, and stop if stinging does not settle. Acids make skin more sensitive to the sun, so wear sunscreen every morning.