Relative bioavailability of calcium-rich dietary sources in the elderly

摘要: BACKGROUND The recent increase in the dietary calcium recommendation from 800 to 1200 mg/d for persons aged > 51 y has made it important identify alternative high-calcium sources that elderly can use meeting their requirement. OBJECTIVE We determined bioavailability of 3 different sources: orange juice fortified with calcium-citrate malate, skim milk, and a carbonate supplement. DESIGN Twelve subjects [9 women men mean (+/- SEM) age 70 +/- 76 6 y, respectively] consumed low-calcium (300 mg/d) (1300 diets three 1-wk periods each during 6-wk crossover study. acute biochemical response was assessed 4-h period after initial breakfast meal diet. RESULTS Postprandial suppression serum parathyroid hormone did not differ significantly between test meals containing calcium-fortified juice, supplement, milk. This finding suggests equivalent. During diet periods, fasting increased by 3% (P < 0.0001), 1,25-dihydroxyvitamin D decreased 20% biomarker bone resorption (serum N-telopeptide collagen cross-links) 14% 0.02) compared period. However, no differences among supplemental were found these calcium-responsive measures or concentration. CONCLUSIONS In subjects, tested equivalent, both postprandial longer-term periods.