Ryan Reynolds took his fans along with him while getting a medical procedure done in hopes of raising awareness about colon cancer, especially in men.

The actor released a video on his YouTube channel on Tuesday in which he undergoes his first ever colonoscopy and discovers that he had a small polyp on his colon. To shed light on this illness and it's preventability, Reynolds teamed up with Lead From Behind, a colon cancer awareness organization that works in association with the Colorectal Cancer Alliance to encourage people to get the procedure done regularly, as well as It's Always Sunny in Philadelphia star Rob McElhenney.

In the video, the two actors explain that they made a bet that if McElhenney learned to speak Welsh, Reynolds would allow the cameras to trail him for the procedure. “He was so sure he said he'd publicly broadcast his colonoscopy if I could do it,” McElhenney announced in Welsh via subtitles. But the Deadpool star added that he also wanted to do this to show how one “simple step” can “literally save your life.” Reynolds continued, “I would never normally have any medical procedure put on camera and then shared. But it’s not every day that you can raise awareness about something that will most definitely save lives. That’s enough motivation for me to let you in on a camera being shoved up my ass.”

During the colonoscopy, the doctor found an “extremely subtle polyp” on the right side of his colon which was immediately removed. As the doctor showed Reynolds the images of the tissue in his colon, he said, “This was potentially life-saving for you—I’m not kidding, I’m not being overly dramatic. This is exactly why you do this. You had no symptoms.” He added, “You are interrupting the natural history of a disease of something of a process that could have ended up developing into cancer and causing all sorts of problems.”

When McElhenney underwent the procedure, they found three polyps in his colon, which the doctor said “were not a big deal, but certainly a good thing that we found them early and removed them.” Going into the procedure, the actor joked, “I figure I can't go wrong in terms of comparing myself to Ryan. They either find nothing and that means my colon was cleaner than his, or they find a polyp and it's either bigger than his, which is awesome, or it's smaller than his, which means I had less of an opportunity to have cancer—either way, I win.” The pair then concluded the video by sharing a message written across a black screen that read, “Colon cancer is preventable. If you’re 45 years or older, ask your doctor about getting a colonoscopy. And help Rob and Ryan kick cancer’s ass.”