From the Manufacturer's Label:
Magnesium Malate is a compound of magnesium and malic acid. Malic acid is a natural fruit acid that is present in most cells in the body and is an important component of numerous enzymes key to ATP synthesis and energy production.
Manufactured by Source NaturalsContains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance