60 male subjects, age 40 to 65 years of age, will be placed on a 3500kcal (55% carbohydrates containing 200 g fructose) for 2 weeks. Half will receive allopurinol mg/day (randomized). At the end of 2 weeks we measure a variety of parameters including fasting glucose and insulin levels (with calculation of HOMA index), serum lipids (including triglycerides and LDL/HDL cholesterol), sitting blood pressure, serum uric acid, weight, and various other measurements (C reactive protein, adiponectin and leptin levels, and urate redox products). Primary endpoint is insulin resistance. Secondary endpoints are blood pressure, lipids, uric acid, weight.