Fair warning: this is gross. Disgusting, even. But it’s a huge content marketing story, so buckle up.

Dr Sandra Lee is a dermatologist. She is perhaps the most famous dermatologist in the world, and it’s all thanks to content marketing. More specifically, popping videos. Even more specifically, her YouTube channel, Dr Pimple Popper.

Prior to Dr Pimple Popper, there was an obscure corner of YouTube home to popping videos. Usually uploaded to personal accounts, they feature people popping massive blackheads, whiteheads, cysts, and other gross skin stuff. Sometimes a professional would do the extraction, politely asking if their patient really wanted to post a video online. Other times, the popping would be a family affair, and the video would go all shaky at the moment of pustule explosion. It was a weird, shameful part of YouTube that frequently saw videos taken down for being gross even as they racked up thousands of views.

Enter Dr Pimple Popper. She represents the professional take on popping videos. A real dermatologist, she films and edits her stuff cleanly and professionally. Her audience gets a clear view of the extraction along with a bit of science and Dr Lee’s kind banter with her patients. Case in point, this video of dilated pore extraction, which is relatively tame compared to her other videos but still gross. By the way, it has forty-one million views.

Dr Pimple Popper has 4.5 million subscribers and her videos have 4.5 billion views. Now, this content promotes her medical practice. She’s a dermatologist, cosmetic surgeon, and skin cancer surgeon. But her content has also created non-medical opportunities for her. She now has her own skincare line. She’s releasing a toy like Operation called Pimple Pete. She’s just launched a TV show on TLC. They even had her on Kimmel.

All this is thanks to content marketing. There are a couple of lessons here. One, it’s okay to be gross. It’s a legitimate market. And two, you can see what kinds of opportunities are out there by just seeing what amateur content creators are doing. Popping videos were a popular genre for years before more professional creators took notice. The model was there, the numbers were there, but no one thought to make content marketing versions of popping videos until people like Dr Lee took notice and built a pimple popping empire.