Why a calcium guideline?
Contemporary diets typically contain less calcium than is needed to ensure the foregoing benefits. Moreover, the disorders concerned relate to several components of contemporary diets, not just to calcium. Because these problems transcend single-nutrient issues, they are fundamentally dietary problems, not nutrient problems. A calcium guideline is needed to round out the current dietary guidelines. At a total diet level, it is worth recalling that the primitive human diet, the one that prevailed during the millenniums of hominid evolution and to which our physiologies were adapted, had a high calcium density, estimated to be 2.9 3.3 mg Ca/kJ (70 80 mg Ca/100 kcal) from vegetable sources alone and substantially higher if, as was often the case, the diet included insect grubs or the bones of small prey or fish (20). In contrast with foods accessible to industrialized populations, calcium was widely distributed in the plant foods available to hominids and other primates (eg, roots, tubers
