The better answer for strong, healthy bones! Calcium may get most of the attention, but nutritionists will tell you that it takes more than calcium to maintain strong bones it takes a healthy ratio of calcium to magnesium. Swanson Calcium Citrate Plus Magnesium is a special mineral formula features the ideal 2-to-1 ratio of calcium to magnesium with 150 mg of calcium and 75 mg of magnesium per capsule.