Bone mineral content and estimated total body calcium in normal adults

Bone mineral content (BMC) was measured in 127 normal subjects, 54 men and 73 women, aged 21-70 years. BMC was a function of age and sex; it was therefore found relevant to give normal values in 10-year age groups for each sex. BMC was furthermore related to height, weight, surface area, and muscular strength but the biological scatter was not reduced by correction for surface area. The normal range is expressed in arbitrary units, mmol calcium/m, and calculated total body calcium in grams. Since the latter expression, after determination of the necessary proportion constants, is independent of apparatus construction and location of measurement, and is dependent on the selection of the reference population, it is recommended that the result be expressed in these grams. It is furthermore concluded that the BMC measurement is excellently suited for determining the effect of treatment on osteopenia in a group of patients but rather unsuitable for diagnosis of osteopenia in the individual patients, whereas two other conditions (as regards clinical applicability) occupy an intermediate diagnosis of osteopenia in a group of patients.