The purpose of this study is to test whether diets that contain potatoes and differ in glycemic index/load will be useful in weight loss, blood sugar control and maintaining current body weight.

The study will examine the effect of including potatoes as part of a calorie restricted diet designed to induce weight loss and improve glycemic control in overweight subjects.

This is a randomized, treatment-controlled, 3-arm, parallel study. The 3 arms of the study will include dietary manipulation in the free-living setting to include potatoes/potato products frequently in the diet (5-7 days / week). Two diets will be energy-restricted (~ 500 kcal deficit /d) for weight loss and the control diet will be prescribed for weight maintenance. The two energy-restricted diets will include further manipulation, such that, one dietary plan will be a high glycemic index (GI) diet and the other a low glycemic index diet.

Inclusion Criteria:

• Men and women
• ≥ 18 years of age who have a body mass index (BMI) of 25 to 35 kg/m2 (inclusive).

Exclusion Criteria:

• Total cholesterol (TC) not greater than 300 mg/dL,
• Fasting triglyceride not greater than 300 mg/dL ,
• LDL cholesterol (LDL-C) not greater than 180 mg/dL,
• Smokers
• Female subjects who are pregnant or lactating
• Subjects taking any medications that would interfere with outcomes of the study
• Subjects with unusual dietary habits (eg., pica)
• Subjects who are actively losing weight or trying to lose weight
• Subjects who are addicted to drugs or alcohol or who are < 1 y in recovery program
• Subjects who present with significant psychiatric or neurological disturbances
• Subjects with known allergy or intolerance to potato products
• Subjects with documented atherosclerotic disease, inflammatory disease, diabetes mellitus, uncontrolled hypertension ( 140/90 mm Hg), chronic lung, renal or liver disease