The effect of soy isoflavone combined with calcium on bone mineral density in perimenopausal Chinese women: a 6-month randomised double-blind placebo-controlled study

Abstract

This study was a prospective, randomised, double-blind, placebo-controlled clinical trial and aimed to compare the effect of placebo, soy isoflavone, calcium and soy isoflavone combined with calcium on bone mineral density (BMD). One hundred and sixty perimenopausal women with osteoporosis or osteopenia were enrolled and randomised into four groups: control, soy isoflavone, calcium and soy isoflavone combined with calcium groups. After intervention, compared with control, isoflavone and calcium groups, mean changes from their corresponding baseline values of BMD, calcium/phosphorus, vitamin D and glutathione peroxidase (GSH-pX) activity were significantly increased, however, those of phosphorus, osteocalcin, luteinizing hormone (LH) and follicle stimulating hormone (FSH) were significantly decreased in isoflavone combined with calcium group. The results showed that soy isoflavone, calcium and isoflavone combined with calcium therapy were effective and safe on attenuating BMD loss in perimenopausal women and isoflavone combined with calcium therapy was better than soy isoflavone and calcium alone.