They’ve been called “miracle drugs,” criticized as “cheating” and debated on every platform from TikTok to the nightly news. GLP-1 medications like semaglutide and tirzepatide have transformed conversations around weight management, diabetes care and longevity. But beyond the hype, what do patients actually need to know?
For answers, NewBeauty turned to obesity and lipid specialist Dr. Spencer Nadolsky, who joined The Beauty Authority to cut through misconceptions and explain where the science stands.
What Are GLP-1s?
“Quick brief: GLP-1 or glucagon-like peptide-1 is a natural hormone that comes from our intestines after we eat specifically carbohydrates,” Dr. Nadolsky explains. These medications are designed to mimic the body’s own GLP-1, but with a powerful upgrade. “Our natural GLP-1 gets broken down within a minute or two. These receptor agonists are designed so our bodies can’t break them down. Scientists have figured out ways to make them stick around longer and have different effects.”
The result is a class of drugs that help regulate blood sugar while also impacting appetite, cravings and eating behavior.
Why They Work for Weight Loss
The biggest game-changer? Appetite regulation. “The medicine hits some receptors in various parts of the brain that then have downstream effects,” says Dr. Nadolsky. “So not just hunger. Cravings go down. Patients talk about not wanting those things anymore. The big thing patients describe is food noise—just not even thinking about food anymore.”
That shift can be life-altering for those who have spent years in a cycle of dieting and regaining. “If you’re just constantly thinking about food, there’s no way you’re going to be successful just with diet and exercise by itself,” he explains.
How Much Weight Loss Can Patients Expect?
Data backs up what patients are seeing in real time. “Diet and exercise on a population level gives around five or six percent total body weight loss. With liraglutide, we saw seven or eight percent,” Dr. Nadolsky says. “Semaglutide was around 15 percent. Tirzepatide studies came out a year or two later and showed 20 to 21 percent total body weight loss. That’s bariatric surgery–level weight loss.”
For many, that number represents hope after years of failed attempts. “Patients finally have hope. A lot of them say, ‘I don’t believe it’s true because I’ve done everything and nothing’s ever worked.’”
Are They Safe?
Critics often point to unknowns around long-term safety, but Dr. Nadolsky says context is key. “These medicines have been out for two decades. They’re extremely safe other than rare side effects,” he explains. Importantly, safety profiles don’t appear to differ much between people using the drugs for diabetes versus weight loss. “The risks are probably similar. It’s just that those rare side effects become more magnified if there’s less clinical upside.”
Do You Lose Muscle?
Another common headline is that GLP-1s cause muscle wasting. Dr. Nadolsky is direct: “I’m not worried about muscle loss. The medicines aren’t catabolic themselves. It’s the calorie deficit that can cause lean mass loss, just like with bariatric surgery or dieting,” he says. His advice: “As long as you’re lifting weights, you can retain most, if not all, of your muscle, and even gain muscle while taking the medicines.”
The “Cheating” Narrative
One misconception Dr. Nadolsky hears constantly is that patients are “taking the easy way out.” He pushes back: “Probably the biggest misconception is that they’re cheating, like they’re a bandaid. The reality is, they’re not fixing the root cause. One of the big causes of weight gain is a dysregulated appetite. These medicines come in and basically block those signals”.
As he points out, anyone who has struggled with obesity knows there’s nothing easy about it. “These patients finally have a tool that works. That’s not a shortcut—it’s medicine addressing biology.”
Will You Need to Stay on Them Forever?
For most, yes. “Most people, if they stop the medicine, will regain the weight,” says Dr. Nadolsky. “This doesn’t mean all people. We probably see around 10 to 15 percent keep the weight off within a year. But in general, expect to be on it long term—similar to blood pressure medicine.”
The Future Is Even More Potent
If semaglutide and tirzepatide feel revolutionary, what’s coming next may be even more powerful. “Now we’re looking at triple agonists,” says Dr. Nadolsky. “GLP-1 with GIP and glucagon. This extra component may increase energy expenditure and mobilize fat tissue. I’m excited because that one is just going to start melting fat off people—bariatric surgery–level weight loss.”
The Takeaway
GLP-1s aren’t a magic wand, but they are reshaping how obesity and metabolic health are treated. They work by calming appetite, reducing cravings and lowering food noise—areas where lifestyle changes alone often fall short.
“These drugs are extremely safe, they’re effective, and for many patients, they’re life-changing,” Dr. Nadolsky says. The future of this class of medicine, he adds, is only getting stronger.
