Effect of Orlistat in Body Composition

The purpose of this study is to determine if a 24 week weight loss program with orlistat 60 mg will produce greater changes in body composition compared to placebo.

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.

Eligibility Criteria:
Inclusion Criteria:

* Aged 18-60 years inclusive
* Body Mass Index (BMI): BMI in the range of 25.0-34.9 kg/m\^2
* Waist circumference:

Females: \> 35 inches Males: \> 40 inches

* Diet:

  1. Normal eating habits, consuming 3 meals a day (breakfast, lunch and dinner)
  2. Willing to follow a hypocaloric diet during the study to achieve weight loss
  3. Willing to take a daily multivitamin for the duration of the study.
* General Health:Good general health with (in the opinion of the investigator) no clinically significant and relevant abnormalities of medical history or physical examination

Exclusion Criteria:

* Pregnant and/ or Breast-feeding women
* Diet/Exercise:Currently on a special diet or who cannot fulfill the dietary requirements of the study.
* Smoking History:a) Smoking cessation within the past 6 months b) Current Smokers
* Allergy/Intolerance: Known or suspected intolerance or hypersensitivity to the study materials and study foods (or closely related compounds) or any of their stated ingredients.
* Medication:

  a) Currently taking medication for weight loss or appetite control. b) Previous Xenical® (orlistat) or alli® use within 3 months of screening date c) Currently taking medication or supplements that influence intestinal transit time and other stool formation parameters or influences cramping (e.g., Anticholinergics (such as atropine) or cholinergics (such as physostigmine), phenothiazines, tricyclic antidepressants, opioid analgesics (including loperamide), calcium channel antagonists, clonidine, cisapride, octreotide. Also, any laxative or antidiarrheal product). d) Currently taking or withdrawn during the past 6 months any drugs with significant impact on body weight (e.g. serotoninergically acting drugs, antidepressants, central adrenergically acting drugs, drugs inhibiting digestion and absorption, appetite suppressants, metformin) e) Currently taking Cyclosporine, Warfarin or Amiodarone HCL
* Disease/Surgery:

  a) History of gastrointestinal disease (e.g., irritable bowel syndrome, diarrhea, inflamed bowel, steatorrhea/fat malabsorption, hemorrhoids, incontinence, pancreatitis). b) History of psychological disorder, including eating disorders such as anorexia nervosa and bulimia c) History of neurological disorder (e.g. seizures, parkinson's disease, Alzheimer's disease) d) History of hypo/hyperthyroidism unless euthyroid and controlled on a stable dose of medication for at least 6 months. e) History of surgery for weight loss f) Uncontrolled hypertension g) Heart Disease h) Diabetes Mellitus (Type 1 and 2) (Fasting Blood Glucose \>126 mg/dL)
* Participant has a known history of panic attacks and/or claustrophobia or other conditions precluding safe EchoMRI, CT or other scanning modalities according to local guidelines, (e.g., pacemaker, hearing aid, metallic body piercing and/or other metal implants) or in the opinion of the Investigator the participant exceeds size limitations for the instruments.
* Participant has had a weight loss or gain of greater than or equal to 3 kg in the 3 months prior to screening.