Author
Roughead, Zamzam | |
LYKKEN, GLENN - UNIV OF NORTH DAKOTA | |
JOHNSON, LUANN - UNIV OF NORTH DAKOTA |
Submitted to: Journal of Federation of American Societies for Experimental Biology
Publication Type: Abstract Only Publication Acceptance Date: 12/2/2002 Publication Date: 3/14/2003 Citation: Roughead, Z.K., Lykken, G.I., Johnson, L.K. 2003. Substituting soy protein for meat protein did not affect calcium (Ca) retention or biomarkers of bone and cardiovascular health in a controlled feeding study of healthy postmenopausal women. The Federation of American Societies for Experimental Biology Journal. 17:A705. Interpretive Summary: Technical Abstract: The effects of substituting soy protein for meat protein on bone and cardiovascular health are not known. The primary aim of this controlled feeding study was to measure Ca retention from a diet with meat (CONTROL) to a diet in which 25 g/day of soy protein (SOY; 3.72 mg isoflavones/g protein) was substituted for 25 g/day of meat protein. The secondary objective was to measure the effects of these diets on indicators of cardiovascular health. Healthy postmenopausal women (n=13, age:52-69 y; BMI: 26.0 ± 5.0) consumed the diets (15% protein, 30% fat; 653 and 740 mg Ca/2200 kcal in the CONTROL and SOY diets, respectively), for 8 wk each, in a randomized crossover design. After 4 wk of equilibration, the 2-d cycle menu was labeled with Ca-47 isotope and its retention was monitored for 28 d by whole body counting. The fractional absorption and final retention of the Ca tracer (mean ± SD) was not different between the diets (absorption: 26.1 ± 7.0, and 27.0 ± 7.0; day 28 retention: 14.1 ± 3.2 and 14.0 ± 4.1, % of dose, for CONTROL and SOY diets, respectively; P>0.05). Diet also did not affect blood and urinary biomarkers of bone metabolism, serum lipids (cholesterol, HDL, LDL, VLDL, triglycerides) and serum homocysteine. In conclusion, a daily substitution of 25 g of a soy protein isolate for meat protein for 8 wk did not affect the efficiency of Ca retention or indicators of cardiovascular status in healthy postmenopausal women. |