Abstract
The relationship of calcium intake to bone and total body health is reviewed tor Caucasian, Black, and Oriental populations. A large body of evidence indicates that calcium intake is an important determinant of bone acquisition during growth, of bone loss with age, and of fracture risk for both Caucasian and Oriental populations. Much less information is available for Blacks. Such evidence as has been published indicates that inadequate calcium intake limits bone acquisition and maintenance in Blacks just as in the other races. However, it is abundantly clear that the intake needed to ensure optimal skeletal status is lower in Blacks than in the other racial groups. Additionally Blacks exhibit relative resistance of the bony resorptive apparatus to parathyroid hormone and consequently have higher blood levels of parathyroid hormone and 1,25(OH)2 vitamin D. These mechanisms lead to reduced urinary calcium loss in both children and adults, and to improved calcium absorption in children - adaptations which facilitate achieving optimal bone status on reduced calcium intakes. However, a growing body of evidence suggests that these same adaptations, despite their protection of the skeleton, contribute to the burden of other chronic diseases in Blacks (particularly hypertension), and that, for them, optimal total body health is achieved at a calcium intake higher than that required for skeletal health.