Malic acid is a type of fruit acid, which is often used as an acidifier for food, and also plays a role in moisturizing the skin, but it generally has no direct therapeutic effect on diseases. Fruit acids include gluconic acid, malic acid, citrus acid and lactic acid, etc. Because most of them are extracted from fruits, they are called fruit acids. Malic acid is a common fruit acid found in all types of fruits. Due to the advantages of malic acid such as high acidity, mild flavor and no damage to oral health, it is being widely used as a food acidifier in the food industry. In addition, fruit acids can help remove dirt and impurities from the surface of the skin, making the facial skin hydrated and smooth, and providing some moisturizing effect. However, malic acid does not have special efficacy and function and cannot be used to treat diseases. If physical discomfort occurs, you should seek medical attention in a timely manner, so as not to delay the condition, do not blindly superstitious prescriptions.