From the Manufacturer's Label
100% Pure Powder
Supports Energy Production**
Critical for Enzyme Function**
Magnesium is a mineral that is critical for energy production and metabolism, muscle contraction, nerve impulse transmission, and bone mineralization.** It is a required cofactor for an estimated 300 enzymes. NOW®Magnesium Citrate Powder is a highly bioavailable form of Magnesium and contains no excipients or fillers.
Manufactured by Now® Foods.Contains no sugar, salt, starch, yeast, wheat, gluten, corn, soy, milk, egg, shellfish or preservatives.