According to the CDC, obesity is a “common, serious, and costly disease.” Between 2017 and March 2020, the prevalence of obesity in the United States was 41.9%. Obesity has been linked to a wide range of health problems, including type 2 diabetes, cardiovascular disease, and certain cancers.
While lifestyle changes, such as diet and exercise, remain the cornerstone of weight management, medication-assisted therapies can be a valuable adjunct to these interventions. In recent years, many studies have confirmed GLP-1 (glucagon-like peptide-1) receptor agonists to be a promising class of medications for weight loss and improved metabolic health.
The Science Behind GLP-1
GLP-1 is a hormone produced in the intestine that plays a key role in regulating appetite, blood sugar, and gut health. It is secreted in response to food intake and stimulates the pancreas to increase insulin secretion and decrease glucagon release, thus, improving glycemic control. In addition to its effects on glucose metabolism, GLP-1 also promotes satiety to reduce food intake by influencing certain brain regions, making it an attractive addition to weight loss interventions.
Since GLP-1 boasts these properties, GLP-1 receptor agonists (GLP-1RA) have been used successfully for the treatment of obesity and related metabolic disorders.
Benefits of GLP-1 for Health and Weight Loss
GLP-1 agonists aren’t a magic bullet for weight loss and metabolic health, but many studies have demonstrated their usefulness as part of a comprehensive approach to weight management that includes lifestyle changes as well as other pharmacological interventions as needed.
Numerous clinical trials have shown GLP-1’s effectiveness in those with and without diabetes. For example, in a clinical trial of semaglutide, the latest GLP-1 approved by the FDA, participants lost 15% of body weight on average – which is up to five times the average weight loss with traditional diet and exercise plans.
As well as weight loss, GLP-1 agonists have been shown to improve glycemic control, reduce blood pressure and cholesterol levels, and significantly reduce cardiovascular and all-cause mortality.
Furthermore, GLP-1 agonists have been shown to improve beta-cell function and insulin sensitivity, potentially leading to better long-term glycemic control and reduced risk of diabetes complications.
Practical Considerations for Prescribing GLP-1 Agonists
Evidence-based guidelines have recommended GLP-1 agonists as a first-line therapy for patients with obesity and type 2 diabetes who have not achieved adequate glycemic control with lifestyle interventions and commonly prescribed medications.
There are several GLP-1 agonists currently available on the market, including exenatide, liraglutide, dulaglutide, semaglutide, and others. They can be taken once weekly, daily, or even twice daily, and differ in their duration of action. In 2019, the oral semaglutide tablet became available in three varying dosages, making it more accessible and increasing patient adherence.
Healthcare providers should consider individual patient characteristics when choosing a specific GLP-1 agonist, such as age, weight, comorbidities, and medication adherence.
GLP-1 receptor agonists are a promising tool in the management of obesity and type 2 diabetes. These medications have been shown to induce significant weight loss and metabolic benefits, with potential advantages over other weight loss interventions and glucose-lowering medications.
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