Eating less and moving more are the basics of weight loss that lasts. For some people, prescription weight loss drugs may help. You'll still need to focus on diet and exercise while taking these drugs, and they're not for everyone. Doctors usually prescribe them only if your BMI is 30 or higher, or if it's at least 27 and you have a condition that may be related to your weight, like type 2 diabetes or high blood pressure. You should be on a low-fat diet (less than 30% of your daily calories from fat) before taking orlistat. If you are committed to making a healthy lifestyle change, try this diet pill. Side Effects Things about sede effects you ch ould know espacially for how eat fast food . include abdominal cramping, passing gas, leaking oily stool, having more bowel movements, and not being able to control bowel movements. These side effects are generally mild and temporary. But they may get worse if you eat high-fat foods.