The body synthesizes malic acid during the process of converting carbohydrates to energy. Extremely preliminary evidence suggests that individuals with the disease fibromyalgia (a disorder that involves fatigue and pain in the muscles) might have difficulty creating or utilizing malic acid. 1 Such a deficiency could interfere with normal muscle function.

Based on this supposition, products containing malic acid and other nutrients were widely offered for sale to people with fibromyalgia. However, there is as yet no evidence that these products are in fact helpful.

Sources

The body produces its own malic acid. Many fruits and vegetables also supply malic acid, most notably apples.

Therapeutic Dosages

In studies and commercial products, the usual dose of malic acid for fibromyalgia is 1,200 to 2,800 mg per day, generally combined with magnesium and other nutrients.

Therapeutic Uses

Malic acid is a major ingredient in combination treatments used for fibromyalgia. However, there is no meaningful evidence that it works.

What Is the Scientific Evidence for Malic Acid?

In a double-blind, placebo-controlled trial , 24 individuals with fibromyalgia were given either placebo or malic acid (1,200 mg per day) combined with magnesium (300 mg daily). 2 After 4 weeks of treatment, there was no significant difference between the placebo and malic acid groups.

The researchers then gave all participants the malic acid combination and increased the dose over a 6-month period. A significant improvement in fibromyalgia symptoms was found after the dose reached about 1,600 mg of malic acid with 400 mg of magnesium. However, because this part of the trial was not blinded or controlled, the results may be entirely due to the placebo effect . Only a properly designed double-blind, placebo-controlled trial of the higher malic acid dose could demonstrate that it really works, and, as yet, none have been reported.

Safety Issues

Malic acid appears to be safe at recommended dosages. A few people reported loose stools at the higher doses in the above studies, possibly due to the magnesium in the combination.

Safety in pregnant or nursing women, children, or individuals with severe liver or kidney disease has not been established.