Name brand GLP-1 drugs like Ozempic and Wegovy have quickly become household names, akin to Tylenol or Advil, and their rise in popularity is only increasing.
Originally developed to treat Type 2 diabetes, the drug also provides weight loss benefits, and more Americans than ever are using it for just that.
Data analyzed by Epic Research showed an increase in use of these drugs by 40-fold between 2017 and 2021, estimating that six million Americans are now on either Ozempic or Mounjaro.
“The rates of obesity have steadily increased over the past few years with more individuals becoming candidates for this type of treatment,” Dr. Eliud Sifonte, a diabetes and metabolism endocrinologist affiliated with NYU Langone Health, told Flow Space. “The agents in this class have revolutionized the treatment of excess fat.”
And while the global rise in obesity rates has underscored the need for more effective and accessible treatment options, traditional approaches to weight loss like proper nutrition and exercise have often been limited by modest outcomes. Semaglutide, the active ingredient in Ozempic, has shifted this paradigm.
Recent studies have shown that patients on high-dose semaglutide can lose an average of 15% to 20% of their body weight, a level previously achievable only with bariatric surgery. With these promising numbers, research is now delving deeper into how to optimize these treatments.
Here’s what the latest science says about GLP-1 drugs and weight loss.
Complex Side Effects Around GLP-1 Drugs
While its benefits are undeniable, the blockbuster growth and use of GLP-1 drugs has also highlighted potential side effects.
The most commonly reported side effects of semaglutide include gastrointestinal issues such as nausea, vomiting, diarrhea and constipation. These symptoms, while typically mild to moderate, can be severe enough to affect daily life. And beyond gastrointestinal effects, researchers are investigating concerns about long-term impacts, such as gallbladder issues, pancreatitis and potential links to thyroid tumors.
A different non-insulin injectable diabetes medication Victoza (liraglutide) was approved in 2010, but in 2013, the FDA issued a warning to consumers of “possible increased risk of pancreatitis and pre-cancerous findings of the pancreas.” And this first warning isn’t an anomaly. In January 2024, the FDA announced it was evaluating reports of hair loss and suicidal thoughts in patients taking Ozempic, Mounjaro or Wegovy.
Plus, rapid weight loss associated with the drug may contribute to gallstone formation, while the emotional and psychological impacts of sudden changes in appetite and body composition remain unstudied.
“These are all major concerns, and should be discussed with your doctor before starting any GLP-1,” Sifonte said.
Tirzepatide takes a front seat
Tirzepatide is a newer medication that targets two hormones instead of just one. It’s thought to be more effective than semaglutide in helping people lose weight, according to recent research published in JAMA Internal Medicine. This is because in addition to reducing and controlling appetite, it also stimulates another hormone, GIP, which is thought to improve how the body breaks down sugar and fat.
In simple terms, semaglutide targets one hormone that makes you feel full and controls blood sugar, while tirzepatide targets two hormones that are shown to have greater improvements in metabolic health, including better insulin sensitivity and fat burning.
Researchers found that people who took semaglutide lost, on average, 3.6% of their body weight after three months; 5.8% after six months; and 8.3% after 12 months.
Those who took tirzepatide lost an average of 5.9% of their body weight after three months; 10.1% after six months; and 15.3% after 12 months.
Researchers concluded that those taking tirzepatide were “significantly more likely to achieve weight loss,” but added that more studies are needed to better understand the full range of benefits and effects both drugs have on patients.
GLP-1’s Surprising Benefits
Beyond its proven ability to help with weight loss, growing research is uncovering GLP-1 drugs’ potential to address a range of other health conditions.
Studies suggest that GLP-1 receptor agonists may improve cardiovascular outcomes, reduce inflammation and enhance metabolic health. This can inadvertently lead to weight loss and improve overall health outcomes.
“Semaglutide might also improve kidney health due to its direct effects on blood sugar control as well as weight,” Dr. John Whyte, chief medical officer at WebMD and a board-certified internist with expertise in drug development and medical policy, told Flow Space. “By lowering blood sugar levels, semaglutide can reduce the strain on the kidneys caused by diabetes. Its ability to promote weight loss can also alleviate obesity-related stress on the kidneys, improving overall kidney function. We’ve also seen data that semaglutide has been shown to have anti-inflammatory and cardiovascular benefits, which can further protect the kidneys from damage.”
“If the heart pumps better,” Whyte added, “the kidney is going to function better.”
The role of GLP-1 medications for treating obesity is just one of several surprising findings uncovered since their introduction to the market. Scientists are finding that the drugs may be useful to treat addiction, dementia and heart disease.
Early studies suggest GLP-1 drugs may reduce cravings for alcohol, nicotine and opioids by modulating the brain’s reward pathways. One study in the journal Addiction found that people addicted to alcohol who also had a prescription for Ozempic or similar drugs had a 50% lower rate of binging alcohol, compared to those who were not on the medications. Whyte says the significant reduction in alcohol use can lead to weight loss and overall improved health outcomes.