Soy isoflavones improve insulin sensitivity without changing serum leptin among postmenopausal women

Objective To investigate the effect of a soy isoflavone extract over insulin sensitivity and plasma leptin levels.Methods Eighty postmenopausal women were randomly assigned to participate for 24 months either to a physical exercise and Mediterranean diet program (Control group: CG) or this intervention plus a daily oral intake of a soy isoflavone extract (Soy isoflavone group: SIG). Anthropometry, body composition analysis, blood biochemistry, menopausal symptoms and health-related quality of life were assessed at baseline and every 6 months.Results Sixty-five women completed the protocol with no differences found among groups at baseline in age and time since the menopause. At month 24, body mass index (BMI) was lower in the SIG as compared to the CG. Fat mass, glucose, insulin, HOMA-IR, tumor necrosis factor-α (TNF-α), Kupperman Index and Cervantes Scale values significantly decreased in the SIG as compared to baseline and to CG values. Kupperman scores and serum TNF-α levels significantly decreased in ...