Iranian Journal of

Background: Little evidence exists regarding the effects of soy consumption on the metabolic syndrome in humans. We aimed to determine the effects of soy consumption on components of the metabolic syndrome, plasma lipids, lipoproteins, insulin resistance and glycemic control in postmenopausal women with the metabolic syndrome.

Methods: This randomized cross-over clinical trial was undertaken on 42 postmenopausal women with the metabolic syndrome. Participants were randomly assigned to consume a control diet (Dietary Approaches to Stop Hypertension= DASH), soy protein diet, or soy nut diet, each for eight weeks. Red meat in the DASH diet was replaced by soy protein in the soy protein period and by soy nut in the soy nut period.

Results: Total cholesterol was significantly reduced compared to the control (P<0.01) and soy protein groups (P<0.01). The results were the same regarding the fasting insulin serum (P<0.01 compared with the control and soy protein group), HOMA-IR (P<0.01 compared with the control and soy protein group), Fasting blood sugar (P<0.01 compared with the control and soy protein group), and LDL cholesterol (P<0.01 compared with the control and P<0.05 compared with the soy protein group). Both soy nut and soy protein reduced Apo B100 compared to the control group (P<0.01).  

Conclusion: Short-term soy nut consumption improved glycemic control and lipid profiles in postmenopausal women with the metabolic syndrome