The aim of the present study was to evaluate whether an in vivo treatment with an antioxidant vitamin (vitamin C) might substantially affect resistin serum levels. For this purpose, serum resistin values were evaluated in a group of healthy subjects, randomized to receive orally 2 g ascorbic acid for two weeks. Values of fasting glucose, insulin, total and HDL-cholesterol, triglycerides, C-reactive protein (CRP), and markers of oxidative stress were measured.