This study is an NIH-funded clinical trial conducted at Duke Medical Center evaluating the effects of the DASH diet alone and combined with a behavioral weight loss program on blood pressure and various vascular measures. Eligible patients must be unmedicated with blood pressure values ranging from approximately 130/85 to 159/99. Our primary hypothesis are as follows: (1) The DASH diet alone and combined with a behavioral weight management program will result in greater BP reductions than Usual Care controls at the end of the 4 month treatment period; (2) The DASH diet in combination with a behavioral weight management program will be more effective in lowering BP than the DASH diet alone; (3) The DASH diet alone and the DASH diet combined with the behavioral weight management program will result in greater improvements in cardiac, metabolic, and vascular function compared to the control condition; and (4) The combined DASH diet and weight management intervention also will be the most effective treatment in maintaining BP reductions at 1-year follow-up.