Yonsei Med J.  2016 May;57(3):681-689. 10.3349/ymj.2016.57.3.681.

Soy Protein Supplementation Reduces Clinical Indices in Type 2 Diabetes and Metabolic Syndrome

• Zhang XM
• Zhang YB
• Chi MH

• KMID: 2374089
• DOI: http://doi.org/10.3349/ymj.2016.57.3.681

Abstract

PURPOSE
Clinical trials have studied the use of soy protein for treating type 2 diabetes (T2D) and metabolic syndrome (MS). The purpose of this study was to outline evidence on the effects of soy protein supplementation on clinical indices in T2D and MS subjects by performing a meta-analysis of randomized controlled trials (RCTs).
MATERIALS AND METHODS
We searched PubMed, EMBASE, and Cochrane databases up to March 2015 for RCTs. Pooled estimates and 95% confidence intervals (CIs) were calculated by the fixed-and-random-effects model. A total of eleven studies with eleven clinical variables met the inclusion criteria.
RESULTS
The meta-analysis showed that fasting plasma glucose (FPG) [weighted mean difference (WMD), -0.207; 95% CI, -0.374 to -0.040; p=0.015], fasting serum insulin (FSI) (WMD, -0.292; 95% CI, -0.496 to -0.088; p=0.005), homeostasis model of assessment for insulin resistance index (HOMA-IR) (WMD, -0.346; 95% CI, -0.570 to -0.123; p=0.002), diastolic blood pressure (DBP) (WMD, -0.230; 95% CI, -0.441 to -0.019; p=0.033), low-density lipoprotein cholesterol (LDL-C) (WMD, -0.304; 95% CI, -0.461 to -0.148; p=0.000), total cholesterol (TC) (WMD, -0.386; 95% CI, -0.548 to -0.225; p=0.000), and C-reactive protein (CRP) (WMD, -0.510; 95% CI, -0.722 to -0.299; p=0.000) are significant reduced with soy protein supplementation, compared with a placebo control group, in T2D and MS patients. Furthermore, soy protein supplementation for longer duration (≥6 mo) significantly reduced FPG, LDL-C, and CRP, while that for a shorter duration (<6 mo) significantly reduced FSI and HOMA-IR.
CONCLUSION
Soy protein supplementation could be beneficial for FPG, FSI, HOMA-IR, DBP, LDL-C, TC, and CRP control in plasma.

Keyword

Soy; diabetes; body weight; blood glucose; lipid

MeSH Terms

Aged
Blood Glucose/*metabolism
Blood Pressure
C-Reactive Protein/metabolism
Cardiovascular Diseases/prevention & control
Cholesterol/blood
Diabetes Mellitus, Type 2/blood/*therapy
*Dietary Supplements
Humans
Lipids/blood
Metabolic Syndrome X/*blood/prevention & control
Randomized Controlled Trials as Topic
Soybean Proteins/*administration & dosage
*Soybeans
Blood Glucose
C-Reactive Protein
Cholesterol
Lipids
Soybean Proteins

Figure

• 

  Fig. 1 Flow diagram of included/excluded studies. HOMA-IR, homeostasis model of assessment for insulin resistence index; TG, triglyceride; CRP, C-reactive protein; T2D, type 2 diabetes; MS, metabolic syndrome; SBP, systolic blood pressure; DBP, diastolic blood pressure; LDL-C, low-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol; TC, total cholesterol.

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