Calcium absorptive consistency.
Calcium absorption efficiency was measured two or three times each in 74 premenopausal and 142 postmenopausal women under conditions predicted to alter absorptive performance. A woman's absorptive consistency was evaluated across differing loads, differing intervals, and substances of differing intrinsic absorbability. In all these circumstances there was a statistically significant correlation between a woman's absorption under differing test situations accounting for up to 60% of the variance typically found in cross-sectional studies. For example, when the same substance but at differing load levels was tested three times over an 8 week period, various coefficients of correlation ranged from +0.773 to +0.849 (P less than 0.001). Even over intervals as long as 5 years correlation of absorption fraction within individuals remained significant (r = +0.487, P less than 0.001).
Heaney
R P
RP
Center for Hard Tissue Research, Creighton University, Omaha, NE.
Weaver
C M
CM
Fitzsimmons
M L
ML
Recker
R R
RR
D000328:Adult; D002136:Calcium, Dietary / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D007408:Intestinal Absorption; D008875:Middle Aged; D012016:Reference Values
D002136:Calcium, Dietary