RT Journal Article SR Electronic T1 Optimizing calcium and vitamin D intake through diet and supplements JF Cleveland Clinic Journal of Medicine JO Cleve Clin J Med FD Cleveland Clinic SP 543 OP 550 DO 10.3949/ccjm.85a.17106 VO 85 IS 7 A1 Holly P. Kilim A1 Harold Rosen YR 2018 UL http://www.ccjm.org/content/85/7/543.abstract AB Calcium, a key component of bone, is obtained through diet or supplements, or both, and vitamin D is necessary for normal calcium absorption. Controversy exists as to the efficacy and even the safety of calcium. Our opinion, backed by studies and guidelines, is that adequate amounts of calcium are a must for patients concerned about bone health, and cardiovascular safety is not a concern.