Obesity: Diagnosis and Treatment

Diagnosis

• A complete history and physical examination are necessary with special attention to medications, herbal remedies, nutritional and exercise history, risk factors for coronary artery disease, and family history of thyroid and cardiac diseases.
  
• Measures of the severity of obesity include BMI, waist circumference, waist–to–hip circumference ratio, and body fat determination, which is based on skin–fold thickness or bioimpedance.
  
• Blood testing includes fasting glucose and insulin concentration, thyroid hormone testing, renal function testing, liver function testing, cholesterol levels, and complete blood count.

Treatment

• Diet, exercise, and lifestyle modification that reduce energy intake and increase energy expenditure are the essentials of treatment. Nutritional interventions are discussed below in Nutritional Considerations.
  
  Physical activity helps individuals retain lean body mass, when compared with food restriction alone, and may better prepare them to keep weight off after the initial loss. Because it takes a great deal of exercise to burn off even a modest amount of weight, physical activity is not a substitute for diet changes.
  
• Several medical therapies are available. However, long–term results of drug therapy have been disappointing, and weight gain occurs once medications are discontinued. Recent evidence suggests that a combination of drugs and behavior therapy has better results than either modality used alone.
  
  Medications that are commonly used (but not necessarily recommended) include appetite suppressants (e.g., sibutramine, phentermine, benzphetamine, phendimetrazine, diethylpropion) and orlistat, which decreases the absorption of dietary fat.
  
• Bariatric surgery (“stomach stapling”) has been used successfully in morbidly obese individuals (BMI >40). However, complications (such as nutrient deficiencies and infection) are common and can be fatal.
  
• Dietary supplements that promise extraordinary weight loss should be avoided. Research studies indicate a lack of weight–loss efficacy for chitosan, chromium picolinate, Garcinia cambogia, glucomannan, guar gum, hydroxy–methylbutyrate, plantago psyllium, pyruvate, yerba mate, yohimbe, and others.
  
  Although ephedra–containing formulas have been found effective for weight control, they carry a high risk of heart disease and are now illegal in the United States.