Malic Acid..Malic acid is a substance found naturally in apples and pears. It's considered an alpha hydroxy acid, a class of natural acids commonly used in skin care products. Also sold in dietary supplement form, malic acid is said to offer a variety of benefits. Benefit: When applied to the skin, malic acid is said to reduce signs of aging, remove dead skin cells, aid in the treatment of acne, and promote skin hydration. It is also used to boost sports