Alpha hydroxy acid is an organic acid found in many cosmetic products. AHAs are known for their exfoliating properties and are often used in anti-aging formulas as well as chemical peels. Common AHAs include glycolic (glycolique) acid, lactic (lactique) acid and citric acid. A popular foot treatment that contains alpha hydroxyl acid is AmLactin Foot Cream, often said to be a miracle cure for calluses.