Malic acid is an organic compound with the molecular formula C₄H₆O₅. It is a dicarboxylic acid that is made by all living organisms, contributes to the sour taste of fruits, and is used as a food additive. Malic acid has two stereoisomeric forms, though only the L-isomer exists naturally.

Is malic acid bad for you?

Malic acid is LIKELY SAFE when taken by mouth in food amounts. It isn't known if malic acid is safe when taken as a medicine. Malic acid can cause skin and eye irritation.

What is malic acid used for?

Malic acid is also found in some citrus fruits. In food, malic acid may be used to acidify or flavor foods or prevent food discoloration. It may also be used with other ingredients in cosmetics. Using malic acid as part of your skin care routine may help with concerns such as pigmentation, acne, or skin aging.