Soy isoflavones do not affect bone resorption in postmenopausal women: a dose-response study using a novel approach with 41Ca.

Abstract

INTRODUCTION The purpose of this 3-way crossover study was to identify the effective dose of soy protein isolate enriched with isoflavones for suppressing bone resorption in postmenopausal women using a novel, rapid assessment of antibone resorbing treatments. METHODS Thirteen postmenopausal women (>or=6 yr since menopause) were predosed with 41Ca iv. After a 200-d baseline period, subjects were given 43 g soy protein/d that contained 0, 97.5, or 135.5 mg total isoflavones in randomized order. The soy protein isolate powder was incorporated into baked products and beverages. Each 50-d intervention phase was preceded by a 50-d pretreatment phase for comparison. Serum isoflavone levels and biochemical markers were measured at the end of each phase. Twenty-four-hour urine samples were collected approximately every 10 d during each phase for 41Ca/Ca analysis by accelerator mass spectrometry. RESULTS Serum isoflavone levels reflected the amount of isoflavones consumed in a dose-dependent manner. None of the isoflavone levels had a significant effect on biochemical markers of bone turnover, urinary cross-linked N teleopeptides of type I collagen and serum osteocalcin, or bone turnover as assessed by urinary 41Ca/Ca ratios. CONCLUSIONS Soy protein with isoflavone doses of up to 135.5 mg/d did not suppress bone resorption in postmenopausal women. This is the first efficacy trial using the novel technique of urinary 41Ca excretion from prelabeled bone.

Statistics

01002002008200920102011201220132014201520162017
Citations per Year

243 Citations

Semantic Scholar estimates that this publication has 243 citations based on the available data.

See our FAQ for additional information.

Cite this paper

@article{Cheong2007SoyID, title={Soy isoflavones do not affect bone resorption in postmenopausal women: a dose-response study using a novel approach with 41Ca.}, author={Jennifer M. K. Cheong and Berdine R. Martin and George S. Jackson and David Elmore and George P. McCabe and Journey R. Nolan and S G Barnes and Munro Peacock and Connie Weaver}, journal={The Journal of clinical endocrinology and metabolism}, year={2007}, volume={92 2}, pages={577-82} }