Treatment of obesity starts with comprehensive lifestyle management (ie, diet, physical activity, behavior modification), which should include the following:

• Self-monitoring of caloric intake and physical activity
• Goal setting
• Stimulus control
• Nonfood rewards
• Relapse prevention

As with all chronic medical conditions, effective management of obesity must be based on a partnership between a highly motivated patient and a committed team of health professionals. This team may include the physician, a psychologist or psychiatrist, physical and exercise therapists, dietitians, and other subspecialists, depending on the comorbidities of the individual patient. Scientific evidence indicates that multidisciplinary programs reliably produce and sustain modest weight loss between 5% and 10% for the long-term.

In January, 2015, the Endocrine Society released new guidelines on the treatment of obesity to include the following:

• Diet, exercise, and behavioral modification should be included in all obesity management approaches for body mass index (BMI) of 25 kg/m ² or higher. Other tools, such as pharmacotherapy for BMI of 27 kg/m ² or higher with comorbidity or BMI over 30 kg/m2 and bariatric surgery for BMI of 35 kg/m ²with comorbidity or BMI over 40 kg/m ², should be used as adjuncts to behavioral modification to reduce food intake and increase physical activity when this is possible.
• Drugs may amplify adherence to behavior change and may improve physical functioning such that increased physical activity is easier in those who cannot exercise initially. Patients who have a history of being unable to successfully lose and maintain weight and who meet label indications are candidates for weight loss medications.
• To promote long-term weight maintenance, the use of approved weight loss medication (over no pharmacological therapy) is suggested to ameliorate comorbidities and amplify adherence to behavior changes, which may improve physical functioning and allow for greater physical activity in individuals with a BMI of 30 kg/m ² or higher or in individuals with a BME of 27 kg/m ² and at least one associated comorbid medical condition (eg, hypertension, dyslipidemia, type 2 diabetes mellitus, and obstructive sleep apnea).
• If a patient's response to a weight loss medication is deemed effective (weight loss of 5% or more of body weight at 3 mo) and safe, it is recommended that the medication be continued. If deemed ineffective (weight loss less than 5% at 3 mo) or if there are safety or tolerability issues at any time, it is recommended that the medication be discontinued and alternative medications or referral for alternative treatment approaches be considered.
• In patients with type 2 diabetes mellitus who are overweight or obese, antidiabetic medications that have additional actions to promote weight loss (such as glucagon-like peptide-1 [GLP-1] analogs or sodium-glucose-linked transporter-2 [SGLT-2] inhibitors) are suggested, in addition to the first-line agent for type 2 diabetes mellitus and obesity, metformin.
• In obese patients with type 2 diabetes mellitus who require insulin therapy, at least one of the following is suggested: metformin, pramlintide, or GLP-1 agonists to mitigate associated weight gain due to insulin. The first-line insulin for this type of patient should be basal insulin. This is preferable to using either insulin alone or insulin with sulfonylurea.
• Angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and calcium channel blockers, rather than beta-adrenergic blockers, should be considered as first-line therapy for hypertension in patients with type 2 diabetes mellitus who are obese.
• In women with BMI of more than 27 kg/m ² with comorbidities or BMI of more than 30 kg/m ² seeking contraception, oral contraceptives are suggested over injectable medications because of weight gain with injectables, provided that women are well informed about risks and benefits (ie, oral contraceptives are not contraindicated).

Weight-loss programs

The 3 major phases of any successful weight-loss program are as follows:

• Preinclusion screening phase
• Weight-loss phase
• Maintenance phase - This can conceivably last for the rest of the patient's life but ideally lasts for at least 1 year after the weight-loss program has been completed

Evidence supports the use of commercial weight-loss programs. A 12-week randomized, controlled trial found that commercially available weight-loss programs are more successful and more affordable than primary care practice–based programs led by specially trained staff.

Pharmacologic therapy

Few drugs are available for the treatment of obesity, and their effectiveness is limited to palliation (ie, production and maintenance of weight loss) rather than cure, with benefits fading when the drugs are stopped. Because all medications inherently have more risks than diet and exercise do, pharmacologic therapy should be used only in patients in whom the benefit justifies the risk.

Surgery

In patients with morbid obesity associated with comorbidities, bariatric surgery is the only available therapeutic modality associated with clinically significant and relatively sustained weight loss. Well-performed bariatric surgery, in carefully selected patients and with a good multidisciplinary support team, substantially ameliorates the morbidities associated with severe obesity.

Comorbidities

The management of obesity is not complete without attention being paid to potential comorbidities. Addressing these issues can have profound effects on the patient's well-being and risk of morbidity and mortality.

According to guidelines released by the American College of Cardiology (ACC), the American Heart Association (AHA), and The Obesity Society (TOS) in 2013, weight loss should be encouraged at a BMI of 25 with just 1 comorbidity (instead of 2 as was the case in previous guidelines), and elevated waist circumference can be one of those comorbidities.

Weight-loss ̶ associated morbidity

Although obesity in itself is associated with increased morbidity and mortality, massive, poorly monitored weight loss and/or weight cycling can have equally dire consequences. Among the important potential complications to watch out for in the setting of weight loss are the following:

• Cardiac arrhythmias
• Electrolyte derangements - Hypokalemia is the most important of these
• Hyperuricemia
• Psychological sequelae - Including depression and the development of eating disorders (particularly binge-eating disorders)
• Cholelithiasis