Longer-term soy nut consumption improves vascular function and cardiometabolic risk markers in older adults: Results of a randomized, controlled cross-over trial.

BACKGROUND: Soy foods may contribute to the beneficial health effects of healthy plant-based diets on the risk to develop cardiovascular disease (CVD). However, their effects on vascular function have hardly been studied. OBJECTIVE: To investigate longer-term effects of soy nut consumption on vascular function and cardiometabolic risk markers in healthy older men and women. DESIGN: Twenty-three healthy participants (age: 60-70 years; BMI: 20-30 kg/m2) participated in a randomized, controlled, single-blinded cross-over trial with an intervention (67 g/day of soy nuts providing 25.5 g protein and 174 mg isoflavones) and control period (no nuts) of 16 weeks, separated by eight weeks wash-out. Adults followed the Dutch food-based dietary guidelines. RESULTS: No serious adverse events were reported and the soy nut regime was well tolerated. Body weights remained stable during the whole study. A higher protein (3.1 energy percent [En%]) and a lower carbohydrate intake (2.0 En%) was observed during the intervention period. Total fat intake was comparable, but that of saturated (-1.3 En%), cis-monounsaturated (-1.5 En%) and cis-polyunsaturated fatty acids (+1.9 En%) differed. Serum isoflavone concentrations were higher after the intervention as compared with the control period (daidzein: 127.8 ng/mL; 95% CI: 74.3-181.3 ng/mL; p < 0.001 and genistein: 454.2 ng/mL; 95% CI: 266.6-641.8 ng/mL; p < 0.001). Brachial artery flow-mediated vasodilation was 1.48 percent points (pp; 95% CI: 0.08-2.89 pp; p = 0.040) higher following soy nut intake. The carotid artery reactivity response and arterial stiffness did not differ. Serum LDL-cholesterol was lower (0.17 mmol/L; 95% CI: 0.02-0.32 mmol/L; p = 0.027), while HDL-cholesterol and triacylglycerol concentrations were comparable. Mean arterial pressure (MAP) was lower (3 mmHg; 95% CI: 0-6 mmHg; p = 0.035). CONCLUSIONS: Longer-term soy nut intake as part of a healthy diet improved endothelial function, LDL-cholesterol concentrations and MAP levels, suggesting mechanisms by which an increased soy food intake beneficially affects CVD risk in older adults. Registered under ClinicalTrials.gov Identifier no. NCT03627637.

The effect of soy nut on serum total antioxidant, endothelial function and cardiovascular risk factors in patients with type 2 diabetes.

BACKGROUND: Type 2 diabetes has a high spread and growing process. Using appropriate food diets is among therapeutic approaches has been applied for diabetic patients. Soya utilization has shown effective results in controlling metabolic abnormalities of these patients. The aim of this study is to investigate the effects of soy nut on glycemic conditions, blood pressure, lipid profile, antioxidant effects and vascular endothelial function of these patients. METHODS: 70 patients with type 2 diabetes were randomly divided into two groups of the test (35 people) and control (35 people). The patients in the intervention group were subjected to 60 g soy nut diet as a part of daily protein for 8 weeks and the control group under the usual diet of diabetes. The fasting glucose, blood pressure, lipid profile, brachial blood flow, the level of serum E-Selectin and total antioxidant capacity in control and test group were assessed before and after diet. RESULTS: Consuming 60 g soy nut for 8 weeks significantly decreased the fasting blood glucose (P = 0.03), total serum cholesterol (P < 0.01), LDL-c (P = 0.01), and E-Selectin (P < 0.01) and increased the capacity of serum total antioxidants (P < 0.01), brachial blood flow (P < 0.01) but didn't have any significant effect on systolic/diastolic blood pressure, HDL-c, and TG. CONCLUSION: Soy nut utilization in the patients with type-2 diabetes can significantly improve the glycemic condition, increase brachial blood flow, decrease E-selectin (improvement of endothelial function), increase serum total antioxidants and lipid profile but has no significant effect on blood pressure and HDL-c.

Clinical and metabolic response to soy administration in older women with metabolic syndrome: a randomized controlled trial.

BACKGROUND: There are many studies on the health effects of soy, only a few describe the effects of the simultaneous use of two types of soy on multiple components of metabolic syndrome (MetS). The present study was designed to determine the effects of roasted soy-nut and textured soy protein (TSP) intake on clinical and metabolic status of older women with MetS borderline parameters. METHOD: This randomized, single-blind, controlled clinical trial included 75 women ≥ 60 years old with a diagnosis of MetS based on ATP III criteria. The participants were randomly allocated into three groups of 25 people; soy-nut, TSP and control groups for 12 week. Fasting blood samples were taken at the beginning and end of the trial to compare the metabolic responses. All participants provided three dietary records and physical activity records during the intervention. We used the Kolmogorov-Smirnov, ANOVA, ANCOVA, paired-t test, and the Generalized Linear Model (GLM) repeated measures analysis. RESULTS: Dietary intake and physical activity of the participants in two groups were not significantly different. After 12 weeks of intervention the participants who received soy-nut had a significant decrease in total cholesterol (TC) (p < 0.001), low density lipoprotein, very low density lipoprotein, apolipoprotein B100, fasting blood glucose, insulin (p < 0.05), HOMA-IR, malondialdehyde (MDA) (p < 0.01) level. Morever, a significant increase in total antioxidant capacity (TAC) (p < 0.01) level compared with the control group. At the same time, the TSP brought significant decrease only in TC, insulin, MDA (p < 0.05) level and a significant increase in total TAC (p < 0.05) level. We did not find any significant effect in intervention groups, on apolipoprotein AI, triglyceride (TG), high density lipoprotein (HDL-C), TG/HDL, C-reactive protein and fibrinogen levels after intervention. CONCLUSION: Short-term intakes of roasted soy-nut and TSP have shown to improve the lipid profiles, markers of glucose intolerance and oxidative stress; although the roasted soy-nut was more effective than TSP. Therefore, a moderate daily intake of roasted soy-nut as snacks or TSP as a meal complement by individuals with borderline parameters of MetS can be a safe and a practical modality to avoid the progression of the disease as well as to limit the side effects of drug intake.Trial registration MUBABOL.REC.1388.1.