Clinical and rodent studies have demonstrated the impact of specific dietary factors in modulating inflammation-related diseases including insulin resistance, type 2 diabetes, and cardiovascular disease. Such dietary factors include polyunsaturated fats, polyphenols, and glycemic index. The investigators know from previous studies in the literature that reducing the glycemic index and increasing the omega-3 fat and polyphenol content of the diet results in improved metabolic indices and reduced inflammation. These improvements can be observed even within the context of persistent obesity. The investigators will implement a reduced-calorie, multi-pronged dietary approach for improving insulin sensitivity and reducing inflammation in obese subjects with the metabolic syndrome. The active diet will include reduced glycemic index foods together with omega-3 fats and polyphenol supplements. The primary hypothesis is that the dietary combination of reduced glycemic index foods, omega-3 fats and polyphenols will work to reduce insulin resistance and inflammation more efficiently than a placebo-controlled, calorie- and macronutrient-matched diet in obese subjects with the metabolic syndrome.

Inclusion Criteria:

• Body Mass Index (BMI): 30.0-40.9 kg/m^2
• Metabolic Syndrome

Exclusion Criteria:

• Diabetes
• Inflammatory diseases
• Eating disorders
• Pregnancy
• Known kidney, coronary, gastrointestinal or peripheral artery disease
• Smoking
• Recent fish oil (>500mg eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA)/day) or polyphenol supplement use
• Recent weight change
• Strenuous exercise
• Fish/food allergies
• Current diabetic, lipid-lowering (fibrates, statins), anti-inflammatory, immune-suppressant, and/or anti-inflammatory hypertension medication use