The Effect of Dried Beancurd on Bone Mineral Density in Postmenopausal Chinese Women: A 2-Year Randomized Controlled Trial

Soy foods contain several components such as isoflavones, calcium and protein that potentially modulate bone turnover and increase bone mineral density (BMD) in postmenopausal women. The study is to evaluate the effect of dried beancurd supplementation on skeletal health in postmenopausal Chinese women. Three hundred postmenopausal women aged 50-65 years were assigned into two groups, receiving 100 g dried beancurd or rice cake a day for 2 years. BMD at the lumbar spine and right proximal femur were measured with a dual-energy X-ray absorptiometry. The bone turnover biomarkers of serum alkaline phosphatase (ALP), bone Gla protein (BGP) and urinary N-telopeptide cross-links of collagen normalized for creatinine (NTX/CRT) were also determined. Serum isoflavone concentration was analyzed by high performance liquid chromatography. The 2-year dried beancurd supplementation generated a significant increase in lumbar spine BMD. An obvious decrease was found in urinary NTX/CRT, and a significant increase was detected in serum isoflavone concentration. The dried beancurd supplementation had no effect on changes of right proximal femur BMD and concentrations of serum ALP and BGP. Daily supplementation of dried beancurd could increase BMD of lumbar spine, but does not slow bone loss at right proximal femur in postmenopausal Chinese women.