Effect of Orlistat in Body Composition

Large amounts of VAT (adipose tissue surrounding the viscera of the organs), is known to be associated with increased risk of heart disease and diabetes. Orlistat (tetrahydrolipstatin or THL) inhibits gastrointestinal lipase and reduces the absorption of dietary fat. The purpose of this study is to to determine if a 24 week weight loss program with orlistat 60 mg would produce greater changes in adipose tissue depots (specifically VAT) compared to placebo. This study will use the Echo MRI technology across multiple sites to measure total fat mass. EchoMRI is a non invasive method ideally suited for studies which track changes in human body composition over time, with measuring times of less than 3 minutes and no radiation exposure.