The main treatment for obesity consists of weight loss via calorie restricted dieting and physical exercise. Dieting, as part of a lifestyle change, produces sustained weight loss, despite slow weight regain over time.
Although 87% of participants in the National Weight Control Registry were able to maintain 10% body weight loss for 10 years, the most appropriate dietary approach for long term weight loss maintenance is still unknown.
Intensive behavioral interventions combining both dietary changes and exercise are recommended. Intermittent fasting has no additional benefit of weight loss compared to continuous energy restriction. Adherence is a more important factor in weight loss success than whatever kind of diet an individual undertakes.Several hypo-caloric diets are effective. In the short-term low carbohydrate diets appear better than low fat diets for weight loss. In the long term, however, all types of low-carbohydrate and low-fat diets appear equally beneficial.
A 2014 review found that the heart disease and diabetes risks associated with different diets appear to be similar. Promotion of the Mediterranean diets among the obese may lower the risk of heart disease. Decreased intake of sweet drinks is also related to weight-loss. Success rates of long-term weight loss maintenance with lifestyle changes are low, ranging from 2–20%.
Dietary and lifestyle changes are effective in limiting excessive weight gain in pregnancy and improve outcomes for both the mother and the child. Intensive behavioral counseling is recommended in those who are both obese and have other risk factors for heart disease.
Five medications have evidence for long-term use orlistat, lorcaserin, liraglutide, phentermine–topiramate, and naltrexone–bupropion. They result in weight loss after one year ranged from 3.0 to 6.7 kg (6.6-14.8 lbs) over placebo. Orlistat, liraglutide, and naltrexone–bupropion are available in both the United States and Europe, whereas phentermine–topiramate are available only in the United States.
European regulatory authorities rejected the latter two drugs in part because of associations of heart valve problems with lorcaserin and more general heart and blood vessel problems with phentermine–topiramate. Lorcaserin was available in the United States and than removed from the market in 2020 due to its association with cancer.
Orlistat use is associated with high rates of gastrointestinal side effects and concerns have been raised about negative effects on the kidneys. There is no information on how these drugs affect longer-term complications of obesity such as cardiovascular disease or death.
The most effective treatment for obesity is bariatric surgery. The types of procedures include laparoscopic adjustable gastric banding, Roux-en-Y gastric bypass, vertical-sleeve gastrectomy, and biliopancreatic diversion. Surgery for severe obesity is associated with long-term weight loss, improvement in obesity-related conditions, and decreased overall mortalit. However, improved metabolic health results from the weight loss, not the surgery. One study found a weight loss of between 14% and 25% (depending on the type of procedure performed) at 10 years, and a 29% reduction in all cause mortality when compared to standard weight loss measures.
Complications occur in about 17% of cases and reoperation is needed in 7% of cases. Due to its cost and risks, researchers are searching for other effective yet less invasive treatments including devices that occupy space in the stomach.
For adults who have not responded to behavioral treatments with or without medication, the US guidelines on obesity recommend informing them about bariatric surgery.
In addition to its health impacts, obesity leads to many problems including disadvantages in employment and increased business costs. These effects are felt by all levels of society from individuals, to corporations, to governments.In 2005, the medical costs attributable to obesity in the US were an estimated $190.2 billion or 20.6% of all medical expenditure while the cost of obesity in Canada was estimated at CA$2 billion in 1997 (2.4% of total health costs). The total annual direct cost of overweight and obesity in Australia in 2005 was A$21 billion. Overweight and obese Australians also received A$35.6 billion in government subsidies. The estimate range for annual expenditures on diet products is $40 billion to $100 billion in the US alone.
The Lancet Commission on Obesity in 2019 called for a global treaty — modelled on the WHO Framework Convention on Tobacco Control — committing countries to address obesity and undernutrition, explicitly excluding the food industry from policy development. They estimate the global cost of obesity $2 trillion a year, about or 2.8% of world GDP.Obesity prevention programs have been found to reduce the cost of treating obesity-related disease.
However, the longer people live, the more medical costs they incur. Researchers, therefore, conclude that reducing obesity may improve the public’s health, but it is unlikely to reduce overall health spending.
Obesity can lead to social stigmatization and disadvantages in employment. When compared to their normal weight counterparts, obese workers on average have higher rates of absenteeism from work and take more disability leave, thus increasing costs for employers and decreasing productivity.
A study examining Duke University employees found that people with a BMI over 40 kg/m2 filed twice as many workers’ compensation claims as those whose BMI was 18.5–24.9 kg/m2. They also had more than 12 times as many lost work days. The most common injuries in this group were due to falls and lifting, thus affecting the lower extremities, wrists or hands, and backs.
The Alabama State Employees’ Insurance Board approved a controversial plan to charge obese workers $25 a month for health insurance that would otherwise be free unless they take steps to lose weight and improve their health. These measures started in January 2010 and apply to those state workers whose BMI exceeds 35 kg/m2 and who fail to make improvements in their health after one year.Some research shows that obese people are less likely to be hired for a job and are less likely to be promoted.
Obese people are also paid less than their non-obese counterparts for an equivalent job; obese women on average make 6% less and obese men make 3% less. Specific industries, such as the airline, healthcare and food industries, have special concerns.
Due to rising rates of obesity, airlines face higher fuel costs and pressures to increase seating width. In 2000, the extra weight of obese passengers cost airlines US$275 million. The healthcare industry has had to invest in special facilities for handling severely obese patients, including special lifting equipment and bariatric ambulances. Costs for restaurants are increased by litigation accusing them of causing obesity.
In 2005 the US Congress discussed legislation to prevent civil lawsuits against the food industry in relation to obesity; however, it did not become law.
With the American Medical Association’s 2013 classification of obesity as a chronic disease, it is thought that health insurance companies will more likely pay for obesity treatment, counseling and surgery, and the cost of research and development of fat treatment pills or gene therapy treatments should be more affordable if insurers help to subsidize their cost.
The AMA classification is not legally binding, however, so health insurers still have the right to reject coverage for a treatment or procedure.In 2014, The European Court of Justice ruled that morbid obesity is a disability. The Court said that if an employee’s obesity prevents him from “full and effective participation of that person in professional life on an equal basis with other workers”, then it shall be considered a disability and that firing someone on such grounds is discriminatory.