For his critics, the stunning physique displayed by basketball player Zion Williamson before the NBA resumed was inevitably the result of improper use of Ozempic. Recommended for diabetics, this drug has gained popularity in recent years on social media thanks to its slimming properties.

A surprisingly gaunt face, bulging biceps, and not an inch of fat in sight. As the 2025-2026 NBA season kicks off on October 21, Zion Williamson arrived at the traditional "media day" this week looking as fit as ever. "We put together a plan with boxing, football field drills, and random exercises. I haven't felt like this since my college and high school days, where I could just walk into a gym and feel good," commented the New Orleans Pelicans star center and first overall pick in the 2019 draft, so often betrayed by his physique since his arrival in the big picture.

Hailed by his fans, who are still waiting to see him play a full season at the age of 25, his physical transformation has also been accompanied by a flood of criticism. For his detractors, it would be too easy to see this weight loss as the simple result of hard work in the gym or a strictly controlled diet. "I know Ozempic when I see it," former NFL player Emmanuel Acho said in a podcast, validating a theory widely shared on social media among some NBA followers.

"I don't even need glasses to know that," Acho continued. "You don't need glasses to spot Ozempic. Zion was supposed to be the next NBA superstar, but it didn't work out. The first thing you have to do is take care of your body, Zion, but also your mind." For the uninitiated, Ozempic works by mimicking a gastrointestinal hormone (GLP-1) that activates receptors in the brain that play a role in regulating appetite. Its primary role is to control and regulate blood sugar, for example, as part of a treatment for type 2 diabetes. The problem is that its use can be misused for the purpose of weight loss.

A drug diverted to weight loss

This slimming property has even earned it a worrying global success on TikTok, where non-diabetics are promoting it wildly, using Ozempic outside its intended use and without paying attention to its potentially serious side effects (nausea, vomiting, constipation, anaphylaxis, etc.). In 2022, billionaire Elon Musk himself promoted it on Twitter, when a user asked him what his secret to losing weight was. The phenomenal success of this drug on social media has even led to supply tensions or stockouts in certain countries such as Australia and Kosovo.

In France, where Ozempic can only be dispensed in pharmacies with a doctor's prescription, and is then reimbursed at 30% by health insurance and 100% if the patient is diabetic, the French National Agency for the Safety of Medicines (ANSM) recently raised its voice. It announced that it had taken legal action to put an end to the illegal sale and advertising on the internet of products presented as anti-obesity treatments. "On the ground, we are seeing a very strong demand for this drug with a desire to lose a few pounds amplified by social networks, like TikTok, and influencers who serve as a sounding board," warned Jean-Luc Faillie, head of the pharmacovigilance center at Montpellier University Hospital, in 2024 in the columns of Le Monde .

"This quest for a slimmer figure pushes some people to do anything to get the product."

Criticism also against Luka Doncic

In the United States, Ozempic quickly became a hit after its approval in 2017, also supported by certain sports and media figures. This summer, Serena Williams , 39 Grand Slam titles to her name and model of body positivity, created a controversy by announcing that she was taking GLP-1, a satiety hormone used for weight loss. Like Zion Williamson, Luka Doncic has also been accused in recent weeks of using Ozempic to achieve a dream physique. While his lifestyle has regularly been criticized, the Slovenian point guard and Lakers star claimed to have followed a training program of rare rigor, supported by a physical trainer, a physiotherapist, and a nutritionist.

But for many, there's no doubt that Ozempic is the only thing that keeps him in his jersey today. "Let's be honest, man. We know Ozempic works fast. He's willing to do whatever it takes to lose weight," Gilbert Arenas, a former Washington Wizards star, publicly criticized him. The rumors were dismissed by the man himself, who has gone from 105kg to 90kg since the Paris 2024 Games. All of this, he says, is thanks to intensive weight training sessions combined with a gluten-free diet and intermittent fasting.

As USA Today points out, weight-loss drugs are not currently banned by the World Anti-Doping Agency (WADA). Ozempic, for example, is an injectable drug containing semaglutide, a molecule that acts by binding to receptors for the hormone glucagon-like peptide-1 (GLP-1), and is subject to WADA's monitoring program. The goal is to "track in- and out-of-competition use patterns," the agency said.