Background. Genistein, a soy-derived isoflavone, might play a preventive role against bone mass loss without the harmful estrogenic activity on reproductive tissues. On the basis of a series of meta-analyses undertaken to identify clinical risk factors for osteoporosis, the Fracture Risk Assessment Tool (FRAX) was developed.

Aim 

To evaluate the fracture probabilities calculated with FRAX in a cohort of osteopenic, postmenopausal women after 24 and 36 months of treatment to better understand the effectiveness of genistein aglycone on postmenopausal bone loss.

Methods 

The parent study was a randomized, double-blind, placebo-controlled trial involving 389 osteopenic, postmenopausal women for 24 months. Subsequently, a subcohort (138 patients) continued therapy for an additional year. Participants received 54 mg of genistein aglycone (n=71) or placebo (n=67), daily. Both arms received calcium and vitamin D₃ in therapeutic doses. FRAX index, lumbar spine and femoral neck bone mineral density (BMD) as well as biochemical levels of bone markers were assessed.

Results 

FRAX index showed a significant decrease in the genistein group compared with placebo after 3 years. BMD increases were greater with genistein for both femoral neck and lumbar spine compared to placebo. Genistein significantly modified bone markers evaluated in the present study.

Conclusions 

After 3 years of treatment, genistein showed positive effects on bone tissue in a cohort of osteopenic, postmenopausal women.