Tulane expert explains why GLP-1 medications are changing obesity treatment

For decades, obesity was often incorrectly viewed as a condition that had a simple cure: Eat less and exercise more.

Today's generation of GLP-1 medications is helping change that line of thinking.

Originally developed to treat Type 2 diabetes, drugs such as semaglutide and tirzepatide have emerged as some of the most effective weight-loss medications ever developed. But according to Shauna Levy, director of the Tulane Weight Loss Center and one of the nation's leading experts in obesity medicine, their biggest impact may be changing how physicians as well as patients understand obesity itself.

"These medications have made the biology of obesity visible in a way that is difficult to ignore," Levy said.

Rather than relying on willpower alone, GLP-1 medications work by mimicking hormones the body naturally releases after eating. Those hormones tell the brain that the body has had enough food, thus reducing hunger, increasing feelings of fullness and quieting the constant cravings many patients describe as "food noise."

"They help turn down the volume on hunger, increase fullness with less food and decrease food noise," Levy said.

The medications also improve blood sugar control by helping the pancreas release insulin when needed and reducing the amount of sugar produced by the liver.

Newer GLP-1 medications can help many patients lose anywhere from 15% to more than 20% of their body weight. But the result is more than weight loss. Researchers have also found benefits that extend well beyond the number on the scale, including reducing the risk of cardiovascular disease, protecting kidney function and improving conditions such as heart failure, obstructive sleep apnea and metabolic liver disease.

Levy cautions, however, that the medications are not appropriate for everyone and should always be prescribed as part of an individualized treatment plan developed with a physician experienced in obesity medicine. They are also not intended for cosmetic purposes.

"One misconception is that these are cosmetic drugs intended only for someone who wants to lose a few pounds," she said. "In reality, they are treatments for a chronic disease that can lead to diabetes, heart disease, liver disease, kidney disease, infertility, sleep apnea, cancer and many other health problems."

She also stresses that the medications are not a replacement for healthy habits. Strength training remains essential for preserving muscle during weight loss, while healthy eating and regular physical activity continue to play critical roles in overall health, she said.

"These medications work best when paired with healthy eating and exercise," Levy said.

At Tulane, Levy said physicians take a multidisciplinary approach that combines obesity medicine, bariatric surgery, nutrition counseling and long-term follow-up rather than relying on medication alone.

Researchers are studying how GLP-1 medications can be used before and after bariatric surgery, how patients can preserve muscle while losing weight and how to improve long-term success. Tulane physicians are also working to improve public understanding of obesity and advocate for broader insurance coverage of evidence-based treatments, which remain out of reach for many patients.

Looking ahead, Levy is excited by a new generation of medications that target multiple metabolic pathways simultaneously and may produce even greater benefits.

But she hopes the most important change is one of perception.

"We are increasingly recognizing that obesity is not a failure of willpower," she said. "It is a chronic, treatable disease."