Submitted to: International Society For Trace Elements Research In Humans
Publication Type: Abstract Only
Publication Acceptance Date: 9/15/2001
Publication Date: 10/1/2001
Citation: Roughead, Z.K., Lykken, G.I., Hunt, J.R. Controlled high meat diets do not adversely affect calcium retention or indicators of bone metabolism in postmenopausal women. 2001. Journal of Trace Elements in Experimental Medicine. v.14. p. 329-330.
Technical Abstract: It is well established that an increased intake of purified proteins leads to an increased urinary calcium loss, however, the effects of common sources of dietary protein (meat) on calcium economy have not been tested with a calcium radiotracer, under controlled diet conditions. Calcium retention from a high meat (HM) and a low meat (LM) diet was determined in a controlled feeding study of healthy postmenopausal women (n=15, age: 48- 74 y; femoral neck density: 0.468-0.884 g/cm**-2). The subjects consumed the LM or HM diets (12 vs.20% of energy as protein, respectively, with 700 mg calcium/2200 kcal), for 8 wk each, in a randomized crossover design. After 4 wk of equilibration, the entire 2-d cycle menu was labeled with Ca-47 radiotracer (as chloride) and its retention was monitored for 4 wk by whole body counting. The calcium retention data, expressed as a % of the initial dose (mean +/- SD), were modeled by a two-component exponential equation (individual R**-2] ranged from 0.98 to 0.99). The biological half-life of the isotope was longer (p<0.04) on the HM diet (56 +/- 6 d) than the LM diet (40 +/- 4 d), however, the final retention of the isotope, 28 days after its administration, was similar between the diets (15.8% +/- 4.0 and 17.2% +/- 4.2 for LM and HM, respectively, p = 0.09). Biomarkers of bone formation (serum osteocalcin, bone-specific alkaline phosphatase) or bone resorption (tartrate-resistant acid phosphatase, urinary N-teleopeptides), and urinary calcium excretion measured at the end of each dietary period (wk 8) were not different between the two dietary treatments. In conclusion, consuming a high meat diet for 8 weeks did not increase calcium requirements or adversely affect indicators of bone status in healthy postmenopausal women.