A systematic review of the scientific data revealed wide variations in weight loss outcomes using different methods.
A systematic review of the medical literature from 2020 to 2024 shows that bariatric surgery (also known as metabolic or weight loss surgery) results in the most significant and sustained weight loss compared with treatment with GLP-1 receptor agonists or lifestyle modifications. These findings were presented at the 2024 Annual Scientific Session of the American Society for Metabolic and Bariatric Surgery (ASMBS).
Researchers found that lifestyle interventions such as diet and exercise resulted in an average weight loss of 7.4%, but that weight was generally regained within 4.1 years. GLP-1 and metabolic and bariatric surgery proved much better. The studies included thousands of patients from clinical studies and multiple randomized clinical trials.
Five months of weekly injections of the GLP-1 semaglutide resulted in a 10.6% weight loss, while nine months of tirzepatide injections resulted in a 21.1% weight loss. But when treatment was stopped, patients regained about half of the weight lost within a year, regardless of which drug was used. With continued injections, patients taking tirzepatide saw their weight loss plateau at 22.5% over 17 to 18 months. Patients taking semaglutide saw their weight loss plateau at 14.9% over the same period.
The metabolic and bariatric surgeries gastric bypass and sleeve gastrectomy resulted in a 31.9% and 29.5% total body weight loss, respectively, one year after surgery. Approximately 25% weight loss was maintained for 10 years after surgery.
“Metabolic and bariatric surgery is the most effective and durable treatment for severe obesity, and unfortunately, it is also one of the most underutilized,” said Marina Kurian, MD, a bariatric surgeon at NYU Langone Health and co-author of the study. “Surgery needs to play a larger role in treating obesity and be considered earlier in the disease progression. Surgery is no longer a last resort and should not be withheld until more severe disease has developed. There is no medical reason for this.”
of ASMBS Report Nearly 280,000 metabolic and bariatric surgeries were performed in the United States in 2022, representing only about 1% of those who met the eligibility requirements based on BMI. According to the Centers for Disease Control and Prevention (CDC), obesity affects 42.4% of Americans. Research has shown that obesity can weaken or impair the body’s immune system, cause chronic inflammation, and increase the risk of many other diseases and conditions. Cardiovascular diseasestroke, type 2 diabetes, and certain cancers.
“Although new drug treatments hold great promise and many more people will be successfully treated, especially as prices fall and insurance coverage expands, we are largely underutilizing our best tool for fighting obesity: metabolic and bariatric surgery, which is safer and more effective than ever before,” said Anne Rogers, MD, president-elect of ASMBS and professor of surgery at Penn State College of Medicine, who was not involved in the study. “For many people, the risks of death from obesity, diabetes and heart disease outweigh the risks of surgery.”
research method
The study included a systematic review of studies that looked at weight loss with lifestyle modification, GLP-1 (semaglutide or tirzepatide), or metabolic and bariatric surgery. GLP-1 data included four randomized clinical trials conducted between 2021 and 2024, while the conclusions on lifestyle modification were based on a systematic review of eight studies. Metabolic and bariatric surgery (gastric bypass and sleeve gastrectomy) were covered by the review of 35 studies, including two randomized clinical trials. In total, the researchers reviewed weight loss outcomes for nearly 20,000 patients.
reference: “Effectiveness and durability of common weight loss methods“The Psychology of the American Metabolic and Bariatric Surgery (ASMBS) 2024 Annual Scientific Meeting” by Megan E Jenkins, Juliane Hafermann, Christine Fielding, Gerhard Prager, and Marina Kurian, June 11, 2024, American Society for Metabolic and Bariatric Surgery (ASMBS) 2024 Annual Scientific Meeting.