[[alternative]]The effect of supplementation with isoflavones on plasma lipids, lipoproteins and urinary estrogen metabolites in postmenopausalwomen with hormone replacement therapy

[[abstract]]Isoflavones are soy phytoestrogens that have been suggested to be cardioprotective and anticarcinogenic. The aims of this trial were to determine the effect of supplementation with isoflavones on plasma lipids, oxidisability of low density lipoprotein ex vivo and two major urinary estrogen metabolites ( as a biomarker for breast cancer risk ) in postmenopausal women with hormone replacement therapy. Thirty-five apparently healthy postmenopausal women having taken combined continuous hormone replacement therapy (premarin 0.625mg, provera 5mg) for at least 3 monthes participated in a single-blind trial. An initial 14-day placebo period of supplementation with maltodextrin was followed by 28 -day periods of supplementation with 114mg isoflavones per day . Venous blood and fist morning urine sample were collected initially and at the end of isoflavone supple-mentation. Supplementation resulted in a 5-fold increase in plasma daidzein concentration. No changes in the plasma concentrations of total cholesterol , triglyceride or total antioxidant status and the urinary excretion of isoprostane or the estrogen metabolites : 2-hydroxyestrone, 16α-hydroxyestrone were observed following supplementation. However an significant beneficial effect was noted for the concentration of HDL-C or LDL-C /HDL-C ratio and in the oxidisability of LDL.The results suggest that isoflavones ameliorate the cardiovascular risk in postmenopausal women, but no effect on urinary estrogen metabolism.