What about Overweight and Obesity in United States?

According to the first CLINICAL GUIDELINE ON THE IDENTIFICATION, EVALUATION, AND TREATMENT OF OVERWEIGHT AND OBESITY IN ADULTS based on evidence from approximately 394 randomized controlled trials (RCTs) found in MEDLINE from January 1980 to September 1997:

Highlights

1. According to the latest statistics from the third National Health and Nutrition Examination Survey, 97 million Americans are overweight or obese.
2. Excess weight is often accompanied by hypertension, dyslipidemia, type 2 diabetes, coronary heart disease, stroke, gallbladder disease, osteoarthritis, sleep apnea and respiratory problems, and endometrial, breast, prostate, and colon cancers.
3. The total costs attributable to obesity-related disease approach $100 billion annually in the United States.
4. Overweight is here defined as a body mass index (BMI) of 25 to 29.9 kg/m2 and obesity as a BMI
   of 30 kg/m2.
5. A variety of effective options exist for the management of overweight and obese patients, including
   dietary therapy approaches such as low-calorie diets and lower-fat diets; altering physical activity patterns; behavior therapy techniques; pharmacotherapy*; surgery; and combinations of these technique.
6. *As of September 1997, the Food and Drug Administration (FDA) requested the voluntary withdrawal from the market of dexfenfluramine and fenfluramine due to a reported association between valvular heart disease and the use of dexfenfluramine or fenfluramine alone or combined with phentermine. The use of these drugs for weight reduction, therefore, is not recommended in this report. Sibutramine is approved by FDA for long-term use. It has limited but definite effects on
   weight loss and can facilitate weight loss maintenance.
7. Weight loss drugs that have been approved by the FDA for long-term use can be useful adjuncts to dietary therapy and physical activity for some patients with a BMI of 30 with no concomitant risk factors or diseases, and for patients with a BMI of 27 with concomitant risk factors or diseases. 
8. Weight loss surgery is one option for weight reduction in a limited number of patients with clinically severe obesity, i.e., BMIs 40 or 35 with comorbid conditions. Weight loss surgery should be
   reserved for patients in whom efforts at medical therapy have failed and who are suffering from the complications of extreme obesity.
9. Randomized trials suggest that weight loss at the rate of 1 to 2 lb/week (calorie deficit of 500 to
   1,000 kcal/day) commonly occurs for up to 6 months.
10. A review of 44 pharmacotherapy RCT articles provides strong evidence that pharmacological therapy (which has generally been studied along with lifestyle modification, including diet and physical activity) using dexfenfluramine, sibutramine, orlistat, or phentermine/fenfluramine results in weight loss in obese adults when used for 6 months to 1 year. Strong evidence also indicates that appropriate weight loss drugs can augment diet, physical activity, and behavior therapy in weight loss. Adverse side effects from the use of weight loss drugs have been observed in patients. As a result of the observed association of valvular heart disease in patients taking fenfluramine and dexfenfluramine alone or in combination, these drugs have been withdrawn from the market. Weight loss drugs approved by the FDA for long-term use may be useful as an adjunct to diet and physical activity for patients with a BMI of 30 with no concomitant obesity-related risk factors or diseases, as well as for patients with a BMI of 27 with concomitant risk factors or diseases; moreover, using weight loss drugs singly (not in combination) and starting with the lowest effective doses can decrease the likelihood of adverse effects.
11. Women in the United States with low incomes or low education are more likely to be obese than those of higher socioeconomic status.
12. In the majority of epidemiologic studies, mortality begins to increase with BMIs above 25 kg/m2.
13. The environment is a major determinant of overweight and obesity. Environmental influences on overweight and obesity are primarily related to food intake and physical activity behaviors. In countries like the United States, there is an overall abundance of palatable, calorie-dense food. In addition, aggressive and sophisticated food marketing in the mass media, supermarkets, and restaurants, and the large portions of food served outside the home, promote high calorie consumption.
14. Since 1995, the use of the prescription drugs fenfluramine or dexfenfluramine for weight loss had increased greatly to 14 million prescriptions in 1'5 years. The increased interest in drug treatment of obesity derives from the poor long-term results often obtained with behavior therapy, including diet and physical activity, as noted earlier in this report. The rationale for the addition of drugs to these regimens is that a more successful weight loss and maintenance may ensue. However, as of September 1997, the FDA requested the voluntary withdrawal of fenfluramine and dexfenfluramine from the market, due to a reported association between valvular heart disease with the drugs dexfenfluramine and fenfluramine, alone or combined with phentermine. In November 1997, the FDA provided clearance for marketing the drug sibutramine hydrochloride monohydrate for the management of obesity, including weight loss and maintenance of weight loss when used in conjunction with a reduced-calorie diet.