Discussion:Kal Magnesium Sustained Release Once Daily tablet provides 500 mg Magnesium in 3 forms for enhanced bioavailability. Magnesium is an essential and important mineral required for over 300 cellular processes and biochemical reactions within the body. On a cellular level, Magnesium is utilized in energy production and storage, cell membranes and balance within the cell. Magnesium plays an important role in supporting healthy bones and muscle.