Malic Acid


Malic acid is a 4-carbon organic acid that is synthesized in humans as one of the steps in the Kreb’s (citric acid) cycle during the production of ATP, which is the body’s primary source of energy. [ Ref. ]  Malic acid also occurs naturally in many fruits and vegetables, and its concentration in apples is especially high, which accounts for it often being called “apple acid.” Because of its role in cellular energy production, malic acid may be helpful to individuals suffering from chronic fatigue and fibromyalgia. It has also been suggested that malic acid can help prevent hypoxia. Because of this, some athletes supplement with malic acid, hoping that it will increase the delivery of oxygen to muscle cells, thereby improving stamina and endurance. Malic acid is an abundant naturally occurring organic acid that is also used widely as an additive in the food and beverage industries to acidify wines, acid drinks, fruit juice, soda water, and various soft drinks. Malic acid is also frequently used in cosmetic formulations as a pH adjuster and sodium malate is used in topical cosmetics as a moisturizing agent for the skin. [ Ref. ]

Active Forms

malic acid


Malic acid is easily absorbed from the gastrointestinal tract.

Toxicities & Precautions


Therapy with malic acid at normal dosage levels has been reported to be safe and without any significant side effects.

Functions In The Body

Energy Production

Malic acid’s primary function in humans is related to its being a primary step in the Kreb’s or citric acid cycle, which results in the production on energy. [ Ref. ]

Clinical Applications

Chronic Fatigue Syndrome

There are no published studies on the use of malic acid in the treatment of chronic fatigue syndrome (CFS). However, CFS is very similar to fibromyalgia, and many clinicians utilize malic acid to help improve energy production in patients with both conditions.


Research in this area is limited. However, the results from one published study reported that patients taking 1,200 mg of malic acid and 300 mg of magnesium twice daily for six months experienced significant reductions in the severity of pain, tenderness, and psychological components associated with the condition. [ Ref. ]

Symptoms and Causes of Deficency

Malic acid is regularly produced in humans, and no deficiency condition has been identified.

Dietary Sources

Malic acid is present in many fruits and vegetables. Some of the highest concentrations occur in apples, cranberries, grapes, and cucumbers.


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