A bizarre theory has taken over social media and Reddit forums in recent weeks: the claim that Ozempic—the diabetes and weight loss drug—can increase penis size. What began as anecdotal posts on Reddit has now snowballed into viral speculation, with some users attributing significant “growth” in their genitals to the medication. But is there any truth to this? Let’s unpack the incident, the science, and what medical experts have to say.
The Reddit buzz: Where the theory beganThe conversation appears to have started on Reddit, where several male users taking Ozempic or similar GLP-1 drugs shared personal experiences.
One user wrote, “I recently measured myself down there and noticed I gained about one inch. Now I think people will say it was because of the fat loss. However, at the time I measured myself before (4 years ago), I was thinner. I also pressed during measurement before, and also this time. Has anyone else noticed this change in themselves?”
Another Redditor added, “Yes. I gained 1.5 inches in length. No joke. Like you I obviously know how long I was before I got very fat. Then after about seven months on Tirzepatide in my case I gained 1.5 inches in length. Definitely not all from weight loss.”
What do the experts say?There is no peer-reviewed research confirming a direct link between Ozempic and an actual increase in penis size. However, experts have explained that any perceived changes are likely due to weight loss—specifically, the reduction of fat around the pubic region, which can make more of the penis visibly exposed. This creates the illusion of growth, but does not reflect an actual increase in size.
According to , the average penis size in the UK has increased from 5.17 inches to 5.63 inches between 2022 and 2024—nearly a 10% rise. In Venezuela, a far more extreme jump was reported: from 1.42 inches to 6.67 inches in the same period.
Dr. Richard Viney, consultant urological surgeon at Queen Elizabeth Hospital in Birmingham, commented on the findings in an interview with , saying: “Men’s penises shorten as they get older (due to) increasing body fat and increasing prostate size drawing the penis back into the body. It is theoretically possible that new drugs like Ozempic and Wegovy, which are used to treat diabetes and obesity, respectively and can cause people to lose weight, could also be a factor. As men lose weight, their penises appear larger.”
Meanwhile, a broader trend has also caught researchers’ attention. A 2023 study in the World Journal of Men’s Health found that average penis size globally had increased by 24% over the past 30 years. Yet, scientists remain unsure about what exactly is driving this change.
Dr. Michael Eisenberg, who authored the study, told Stanford Medicine’s Scope blog: “Any overall change in development is concerning, because our reproductive system is one of the most important pieces of human biology. If we’re seeing this fast of a change, it means that something powerful is happening to our bodies.”