title: Effect of calcium supplements and stage of lactation on the calcium absorption efficiency of lactating women accustomed to low calcium intakes.
abstract: The effect of calcium intake on the calcium absorption efficiency from 100 mL cow milk was measured in lactating Gambian mothers habituated to a low-calcium diet [mean intake 7.08 mmol (283 mg)/d], and compared with UK lactating mothers consuming high-calcium diets [mean intake 29.2 mmol (1168 mg)/d] by using a double stable-isotope technique (oral 44Ca and intravenous 42Ca). In a double-blind trial starting 9 d postpartum, Gambian mothers were given a calcium supplement [17.85 mmol (714 mg)/d] or placebo for 12 mo. At 3 and 12 mo postpartum, mean (+/- SEM) calcium absorption from isotopically enriched milk was 52.3 +/- 3.1% (n = 25) and 47.2 +/- 4.8% (n = 24) in the unsupplemented Gambian mothers and 48.8 +/- 2.8% (n = 28) and 42.9 +/- 3.7% (n = 24) in the supplemented mothers, respectively. There was no effect of supplementation or stage of lactation on the efficiency of calcium absorption. At 3 mo postpartum the UK mothers absorbed 32.2 +/- 3.8% of the isotopically enriched calcium added to milk, which was significantly less than that of the Gambian mothers (P < 0.01).
mesh_terms: D000042:Absorption; D000284:Administration, Oral; D000328:Adult; D000818:Animals; D002118:Calcium / Q000008:administration & dosage / Q000172:deficiency* / Q000493:pharmacokinetics*; D002127:Calcium Isotopes; D002136:Calcium, Dietary / Q000032:analysis / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D005527:Food, Fortified; D005714:Gambia; D006801:Humans; D007275:Injections, Intravenous; D007774:Lactation / Q000502:physiology*; D013058:Mass Spectrometry; D008892:Milk / Q000737:chemistry / Q000592:standards; D006113:United Kingdom
chemical_list: D002127:Calcium Isotopes; D002136:Calcium, Dietary; D002118:Calcium