Your body needs calcium to build strong bones, move muscles, send messages through the nervous system, and circulate blood. Viactiv soft chews provide 650mg of calcium per chew as Calcium Carbonate which has higher levels of elemental calcium (40%) compared to Calcium Citrate (21%). Elemental calcium has a higher load of calcium, by weight, which is immediately useable by the body, providing the amount of calcium in two glasses of milk in just one delicious milk chocolate or caramel soft chew.