Keck Medicine of USC doctors talk about the rise in use of the semaglutide medications known as Ozempic and Wegovy for weight loss.
It’s hard to exist in Los Angeles these days without knowing what the latest trend in weight loss is. The current fad is so ubiquitous that it even made it into a speech at the 2023 Oscars. In this case, it’s Ozempic.
Although Ozempic has gained recent popularity in the media as a new weight-loss drug, it’s been used to treat diabetes for years, and the science behind how it works is nothing new. While Ozempic might have the current spotlight, it’s the lesser-known Wegovy that is actually FDA-approved specifically for weight loss.
What’s the difference between Ozempic and Wegovy?
“Interestingly, there’s a lot of focus on Ozempic, but Wegovy is the one marketed for weight loss,” says Alyssa Dominguez, MD, an endocrinologist at Keck Medicine. Both drugs are essentially the same — semaglutide injections — but they vary in dosage, with Wegovy having a slightly higher maximum dosage.
While some people in the media argue that Ozempic should be reserved for treating people with diabetes, that’s not necessarily the view held by medical professionals, who have worked with the drug for years. In fact, Wegovy was studied specifically for weight loss, and the FDA approved the drug for weight loss in people 12 years and older. Both Ozempic and Wegovy are made by the same company, and the main difference besides dosage is their FDA clearance. Wegovy is approved specifically for weight loss. Ozempic is approved for diabetes management, but some doctors prescribe it to be used off-label (which is when a medication is used to treat a condition other than its FDA-approved criteria) for weight loss, too.
“Typically, I prescribe Ozempic for diabetes and have more often prescribed Wegovy for weight loss,” Dr. Dominguez says. “I have used Ozempic, sometimes, off-label for weight loss, though getting insurance approval for that can be challenging. And of course, when using Ozempic to treat diabetes, weight loss can be a common side effect. People with diabetes are also often struggling with being overweight or obese. So, it’s helpful to have that weight loss, as well.”
In the context of diabetes, these two semaglutide injections have been extremely helpful in treating this chronic disease. Semaglutide was also shown to protect the heart and kidneys.
Obesity is an epidemic. Many people are obese and overweight in the United States. That causes all sorts of problems. So, if we can get them to lose weight easily and simply, why not?Anne Peters, MD, an endocrinologist at Keck Medicine of USC
Anne Peters, MD, an endocrinologist at Keck Medicine, has been working with these types of drugs for 20 years. She also helped write both national and international guidelines for treatment of diabetes for the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD).
“One of the challenges with these medications is that obesity isn’t recognized as a disease in this country, so people can’t get them covered with insurance,” she says. Additionally, the surge in people using them for treating obesity has caused a supply shortage.
“I’m in favor of these drugs when used correctly,” Dr. Peters says. “The problem is using these in people who aren’t overweight. I don’t think it’s bad that people are using it for weight loss, in general. However, right now it’s a supply issue.”
In the United States, 41.9% of the population were reported as obese in 2017, according to the Centers for Disease Control and Prevention (CDC).
“Obesity is an epidemic,” Dr. Peters says. “Many people are obese and overweight in the United States. That causes all sorts of health problems. So, if we can help people lose weight easily and simply, why not use all the tools we have available?”
How much weight do people on Ozempic or Wegovy lose?
In a clinical trial where people were given maximum doses of Wegovy, people lost on average 15% of their body weight.
“This is a really great result,” Dr. Dominguez says. “Based on the results of that trial, as long as people stayed on the drug, they were able to maintain that weight loss, which is one of the things that can be very difficult with diet and exercise alone.”
But, contrary to what some people may think, Ozempic and Wegovy are not cure-alls for weight loss.
“It’s going to take somebody and make them lose maybe 25 pounds, which is great, but for many people that may not be enough all by itself,” she says.
“There’s a huge range of how much weight a person may lose while using these medications,” Dr. Peters says. “Some people may lose 50 pounds, but others won’t lose any. Results depend on the person and other behavioral modifications, like diet and exercise.”
How do Ozempic and Wegovy work?
Semaglutide, known as Ozempic and Wegovy, works by mimicking a naturally occurring hormone called glucagon-like-peptide-1 (GLP-1). GLP-1 has several functions in your body. After you eat, your GLP-1 level rises, and the molecules travel to your brain, to help regulate food intake.
- They tell your brain that you’re less hungry.
“In your brain, Ozempic and Wegovy bind to receptors that have to do with satiety, so they increase your feeling of fullness. In essence, your brain tells your body it’s full, even though you’re consuming less food and calories,” Dr. Peters says.
- They slow your digestion.
Ozempic and Wegovy work to slow gastric emptying, so you can’t put as much food into your stomach as you can normally. This is similar to the effect of bariatric surgery, so that you stay fuller for longer.
- They improve your blood sugar, if you have diabetes.
“The drug also helps the beta cells in your pancreas make more insulin,” Dr. Peters says. In people with type 2 diabetes, this directly helps lower blood sugar levels, but in people without diabetes, their blood sugar levels remain in the normal range.
- But they stop working if you stop taking them.
There’s a weight-loss plateau. It doesn’t work forever, and at some point, your body reestablishes its set point, and your weight loss stops or plateaus. And, if you stop taking the drug altogether, your hunger returns, because you’ve changed the mechanism, and many people gain weight back.
“I wish we knew more,” Dr. Peters says. “I wish we understood the pathogenic mechanisms behind people becoming overweight. Because it’s not just that people are weak-willed and eat way too much. There are many reasons why people get to the point where they’re overweight and obese — various biological mechanisms, emotional eating, different metabolisms and more — and I would love to figure out how to fix the root causes.”
But obesity is historically very hard to treat, because once you are overweight and you try to lose weight, all you want to do is eat to get back up to your prior weight, Dr. Peters says.
“Set weight points are real, and I think Ozempic and Wegovy actually just bring your set point down, maybe 15 pounds less,” she says.
What types of people are prescribed Ozempic or Wegovy?
There are specific criteria for prescribing someone Ozempic or Wegovy.
“For prescribing Wegovy for weight loss, a person must have a body mass index (BMI) of 30 or greater. It’s also approved for use in people with a BMI of 27 or greater, who have an accompanying overweight- or obesity-related condition, such as high blood pressure or sleep apnea,” Dr. Dominguez says.
Ozempic is sometimes prescribed off-label for weight loss but is mostly used to treat people with diabetes, she says.
Health insurance companies can have other guidelines for covering Ozempic and Wegovy. Speak with your doctor and health insurance provider to see if you qualify for these drugs.
What advances are on the horizon for weight-loss and obesity treatment?
“Even better drugs of this class are in the works, where two or more hormones will be combined to aid in weight loss,” Dr. Peters says. But the main challenges are making these medications less expensive and more effective for long-term use.
What do you think about the claim that these drugs are harmful because people shouldn’t need to lose weight?
“To me, this issue is not about appearance, it’s about health,” Dr. Peters says. “I think we’re lacking a lot of knowledge in terms of how to prevent obesity, which is my first hope. But, if people are already overweight or dealing with obesity, it’s important to help them achieve and maintain a healthy weight. Studies continue to show that keeping a healthy weight has a real positive impact on your overall health and well-being. I just want people healthy, period.”