Effect of calcium carbonate particle size on calcium retention in adolescent girls
Abstract
In an era where adolescents fail to achieve the recommended calcium (Ca) intake, effort is needed to increase the absorption of the Ca consumed. Previously we reported that substituting small (13μm) for large (18.5μm - commercial standard) Ca carbonate (CaCO3) particles in diets of growing female rats resulted in higher Ca retention. Here we assessed the effect of large versus small CaCO3 particle size and small CaCO3 versus placebo on Ca retention in adolescent girls. Twenty-eight adolescent girls participated in two 3-wk controlled feeding trials separated by a 1-wk washout period. During both sessions, the subjects consumed a diet containing 804mg Ca/d. Using a cross-over design, one group (n=18) received an additional 650mg/d Ca via supplementation delivered twice a day in a 325mg Ca dose as either the large or small particle supplement. A second group (n=10) received the small particle CaCO3 or placebo. All 24-h urine and feces were collected and analyzed for Ca content. The overall balance results (Ca intake – urine Ca – fecal Ca) indicated that the small particle CaCO 3 resulted in greater Ca retention compared to placebo (p<0.05). However, there was no significant difference (p>0.05) in Ca retention due to particle size of the CaCO3. Thus, the rat model did not predict the effect of particle size on Ca retention in humans. Unlike the rat study which started the treatment diet during weanling and continued throughout adolescence, the human subjects received the treatment during peak skeletal acquisition. Perhaps the overwhelming effects of growth during puberty overpowered the more subtle effect of CaCO3 particle size treatment.
Degree
Ph.D.
Advisors
Weaver, Purdue University.
Subject Area
Nutrition
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