New Review Highlights Safety and Effectiveness of GLP-1s for Obesity

A new review of randomized controlled trials suggests that GLP-1 medications are both safe and effective for people living with obesity. This finding, highlighted in a recent Substack article, brings important clarity to the ongoing conversation around these powerful new tools for weight management Review of randomized controlled trials supports safety and effectiveness of GLP-1 medications for obesity.

You might be wondering what "randomized controlled trials" means for you. These types of studies are considered the gold standard in medical research. They help scientists understand if a treatment works and if it's safe by comparing it to a placebo or another treatment, with participants randomly assigned to groups.

What GLP-1s Do for Weight Management

GLP-1 receptor agonists, like semaglutide (brand name Wegovy) and tirzepatide (brand name Zepbound), are FDA-approved to help adults and some adolescents manage their weight. According to the FDA-approved label for Wegovy, it's indicated for chronic weight management in adults and pediatric patients aged 12 years and older with obesity or overweight with at least one weight-related condition. Similarly, the FDA-approved label for Zepbound specifies its use for adults with obesity or overweight and at least one weight-related comorbid condition.

These medications work by mimicking natural hormones in your body that regulate appetite and blood sugar. This can lead to feeling fuller longer and eating less, which helps with weight loss.

Evidence of Effectiveness

The review specifically highlights the effectiveness shown in these rigorous trials. For example, a study published in Nature Medicine in July 2024, part of the SELECT trial, demonstrated the long-term weight loss effects of semaglutide in individuals with obesity but without diabetes Long-term weight loss effects of semaglutide in obesity without diabetes in the SELECT trial..

Beyond just weight loss, these medications can also have other health benefits. A prespecified analysis of the SELECT trial, published in The Lancet in August 2024, investigated semaglutide's impact on cardiovascular outcomes in patients with obesity and existing heart failure Semaglutide and cardiovascular outcomes in patients with obesity and prevalent heart failure: a prespecified analysis of the SELECT trial.. This suggests a broader positive effect on health for some individuals.

It's important to note that maintaining weight loss often requires ongoing treatment. A study in Diabetes, Obesity and Metabolism from August 2022, which was an extension of the STEP 1 trial, showed that participants experienced weight regain and changes in cardiometabolic effects after stopping semaglutide Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension.. This underscores that GLP-1s are typically a long-term treatment.

Understanding the Safety Profile

Like all medications, GLP-1s come with potential side effects. According to the FDA-approved label for Wegovy, common adverse reactions reported in clinical trials (occurring in 5% or more of patients) include nausea, diarrhea, vomiting, constipation, and abdominal pain. The FDA-approved label for Zepbound lists similar common side effects like nausea, diarrhea, vomiting, constipation, and abdominal pain, along with injection site reactions and fatigue.

Serious adverse reactions, though less common, are also listed on the FDA labels. These include a risk of thyroid C-cell tumors (seen in rodent studies, but human relevance is unknown), acute pancreatitis, acute gallbladder disease, and acute kidney injury. It's crucial to discuss all potential risks and benefits with your healthcare provider.

What This Means For You

• Evidence-Backed Confidence: The review reinforces that GLP-1 medications have been thoroughly studied in randomized controlled trials, supporting their role in weight management for many.
• Long-Term Approach: These medications are generally intended for long-term use, and stopping them may lead to weight regain.
• Know the Side Effects: Be aware of common gastrointestinal side effects and the potential for more serious, though rare, adverse reactions. Always discuss any concerns with your prescriber.

Not medical advice. Talk to your prescriber about your situation.