Obesity means having too much body fat while overweight means weighing too much. BMI, or body mass index, is a simple and widely used method for estimating body fat. Obesity increases your risk of diabetes, heart disease, stroke, arthritis and some cancers. Losing even 5 to 10 percent of your weight can delay or prevent some of these diseases. There are several treatment options for the management of overweight and obese individuals, including diet therapy, changes in physical activity, behavioral therapy, drug therapy, surgery and a combination of these. Initial Goal of any Therapy is to reduce the Body weight by 10% and then any further steps can be taken. Lifestyle modifications such as increasing physical activity and decreasing calorie intake are recommended instead of "dieting." Exercising is important to any good weight loss program. 45 minutes of aerobic exercise a day is the equivalent of losing 400-800 Calories based on the intensity. Obese patients should start slowly with low-intensity walking or swimming and advance intensity as tolerated. Combining behavioral therapy, diet therapy, and increased physical activity are a part of initial "therapy" for weight loss. It should be continued for at least 6 months before proceeding to drug therapy. Bariatric surgery produces weight loss by restricting food intake and, in some cases, interfering with nutrition through malabsorption. There are four types of operations that are commonly offered adjustable gastric band (AGB), Roux-en-Y gastric bypass (RYGB), gastric sleeve (GS), and biliopancreatic bypass with a duodenal switch (BPD).