Maintaining bone density and strength is about adding calcium. Benefits at a Glance: Highly absorbable nutrients for greater bone density Provides three different, well-absorbed forms of calcium Includes the critical bone minerals magnesium, boron, zinc, manganese, and silicon Contains 1,000 IU of vitamin D3 per serving Healthy bone density requires calcium. the right kind The most abundant mineral in the body, calcium is primarily found in bones and teeth.