You may have seen advertisements and media reports about a class of type 2 diabetes drugs called GLP-1 agonists that are now approved for weight-loss treatment in people who don’t have diabetes. But are these medications the best choice for losing weight? Do they really work? And are there side effects? We’re breaking it all down.
Lifestyle Changes and Weight Loss
While medications can be part of a comprehensive weight-loss plan for certain people, they are not the whole answer and come with a variety of requirements. The best approach to weight loss is always to first make behavioral and lifestyle changes. These guidelines, necessary for long-term success, may include:
- Exercise: Strive for at least 30 minutes of moderate exercise, like walking, every day.
- Diet: Eat a high-protein breakfast. Limit sugary drinks. Focus on whole foods. Eat mindfully; slow down and savor food.
- Sleep: Aim for seven hours of sleep every night. This is key to successful weight loss.
Who Can Take GLP-1 Agonists for Weight Loss?
Along with lifestyle choices, GLP-1 (glucagon-like peptide-1) agonists—used to control blood glucose levels in people with diabetes—have been approved by the FDA as a weight-loss treatment for certain people who struggle with significant appetite or cravings. Patients typically need to meet one of two criteria to qualify for GLP-1 agonists:
- Have a BMI of 30 or higher
- Have a BMI of 27 and other significant medical conditions
Two GLP-1 medications are currently approved for weight loss: Liraglutide (Saxenda) and semaglutide (Wegovy). Both medications are approved for long-term use. Some other GLP-1 drugs like Ozempic are approved for diabetes, but do not have full approval for weight-loss use.
GLP-1 agonists are not recommended for pregnant people or those with a personal or family history of medullary thyroid cancer of multiple endocrine neoplasia (MEN2). There are also precautions for people with a history of pancreatitis or who have active gall bladder disease. Your doctor will provide guidance on whether you are a good candidate for medication and which is most appropriate for you.
How GLP-1 Medications Work
GLP-1 agonists do not directly cause weight loss. The medications work in an area of the brain called the hypothalamus to reduce a person’s appetite or cravings. They also delay the stomach from emptying, allowing someone to stay full, or satisfied, on a smaller amount of food for a longer period of time after a meal.
The GLP-1 agonists that are approved for weight loss are injectable medications taken by a shot. Liraglutide (Saxenda) is taken daily while semaglutide (Wegovy) is taken weekly.
Side Effects of GLP-1 Drugs
GLP-1 agonists medications are titrated (measured and adjusted) up over time to reach a maintenance dose and minimize side effects. The most common side effects are nausea, indigestion, diarrhea or constipation, and fatigue. These symptoms are more pronounced at higher doses. The side effects do not usually create a need to discontinue the drug.
Weight-Loss Success Rates
Of course the question everyone wants answered is: How effective are GLP-1s in helping people lose weight? Here are the findings after approximately one year of treatment:
- Saxenda: 21 pounds (6.4 percent) lost
- Wegovy: 33 pounds (15 percent) lost
Wegovy tended to have higher rates of gastrointestinal side effects.
Like other weight-loss medications, people regained most of their lost weight if they stopped the medications, especially before one year.
Bariatric Surgery vs. Medication Treatment
The amount of weight people lose by using medications has not yet reached the level of weight loss achieved through bariatric surgery. In addition, medications are very expensive, need to be refrigerated, and 90 percent of people experience some side effects—usually mild to moderate.
If you are considering weight-loss treatment, talk to your doctor or an obesity medicine specialist about the best approach for you.