Phytoestrogens May Reduce Cardiovascular Disease Risk in High-Risk Group

HULL, England--Dietary supplementation with soy phytoestrogens improves various markers of glucose metabolism and circulatory health, indicating a reduced risk of cardiovascular disease in postmenopausal women with Type II diabetes, according to a study in the October issue of Diabetes Care (25:1709-14, 2002) (care.diabetesjournals.org). Specifically, researchers from the University of Hull and Hull Royal Infirmary noted soy protein and isoflavone intake improved the women's insulin resistance, glycemic control and serum lipoproteins.

Researchers began their line of study based on the premise that phytoestrogen intake has been shown to reduce risk factors for cardiovascular disease, and Type II diabetes increases the risk of heart disease, especially in postmenopausal women. A total of 32 postmenopausal women with diet-controlled Type II diabetes were randomly assigned to take phytoestrogens (30 g/d of soy protein and 132 mg/d of isoflavones) or placebo (30 g/d of cellulose) for 12 weeks. After a two-week washout period, the groups switched regimens.

Results indicated that compliance with the regimen was greater than 90 percent for both treatment phases. When compared with the mean percentage change from baseline seen after 12 weeks of placebo, phytoestrogen supplementation lowered mean values for fasting insulin, insulin resistance, total cholesterol, low-density lipoprotein (LDL or "bad") cholesterol and the ratio of total cholesterol to high-density lipoprotein (HDL or "good") cholesterol. Researchers concluded these results indicated intake of soy protein and isoflavones improves the cardiovascular risk profile of postmenopausal women with Type II diabetes.