At least one billion people worldwide are overweight (BMI ≥ 25 kg/m2) and at least 300 million are obese (BMI ≥ 30 kg/m2). Obesity is a plaque of developed countries, a direct consequence of increases in energy intake and decreases in energy output. Unfortunately obesity has great consequence to the health of a nation, being linked to numerous chronic diseases. In a study of the western hemisphere, especially Brazil, Mexico, Canada and the United States it was found that the United states had the highest rates of obesity, but the other countries were not far behind. Data also indicates that obesity is increasing every year as underdeveloped countries adopt Western lifestyle habits. As mentioned above the easiest explanation of the cause of obesity is an increased energy intake and decreased energy expenditure, there are however more causes. These stem from familial, social, societal, cultural, governmental, and environmental factors. Because the different causes vary from country to country, making a plan of action to reverse this epidemic can be problematic. A specialized plan should be tailored for each country. Obesity, being preventable in most cases, represents one of the most costly consequences of people’s neglect for preventative medicine. Guidelines for a healthy lifestyle used to promote exercise to be physically fit, a shift has occurred recently to do physical activity to become healthy. The weekly recommendation includes 30 minutes of moderate intensity physical activity 5 days a week or 25 minutes of vigorous physical activity 3 days a week. In addition to one of these options people should do strength training 2 days a week. Increasing physical activity has a greater impact on overall health than any other lifestyle change. All-cause mortality is decreased by increasing physical fitness. With all these things in mind, Americans need to get off their lazy butts and become physically active. Governments need to encourage this as well.