In a roundabout way, Denton Cooley, the revered Houston cardiac surgeon who was the first to implant an artificial heart in a living patient, may be responsible for TV show My 600-lb Life. Cooley observed Younan Nowzaradan performing a heart operation when the younger man was doing his surgical training in Nashville, and asked him to come to the Texas Heart Institute for his fellowship. That was in 1976.

In the ensuing years, Nowzaradan has gone from heart surgeon to general surgeon to weight loss specialist to TV star. Nowzaradan, Dr. Now on TV, leaves his age at “old enough to do surgery" and says that as a young boy in Tehran, Iran, he never imagined becoming anything but a surgeon. He earned his medical degree from the University of Tehran in 1970, but now considers Houston home.

In Nowzaradan, cable network TLC found a devoted advocate for weight-loss surgery who also happens to have a flair for TV. Early network specials in which he appeared have B-movie-worthy titles like Half Ton Teen and World’s Heaviest Man Part II.

How did My 600-lb Life come to be? “It just happened,” says Nowzaradan. “I was operating on a lot of 600-pound people.” In every episode of the show, patients from across the country take journeys to Houston that are arduous—and part of the drama—due to their size, all to receive treatment from Nowzaradan, who greets them wearing his trademark gold stethoscope.

But the drama isn’t manufactured. “I never let the camera change my behavior toward any patient,” he maintains. “I do exactly the same thing if the camera is there or not.”

When he’s not being filmed, the doctor sees Houstonians, yes, but also patients from around the world—Saudi Arabia, he says, is especially common. They’ve likely heard his name from TV, but he stands out as a doctor of last resort who will turn no one away—and has a skillset that straddles the worlds of cardiology, general surgery and plastic surgery, as well as a steel-trap memory that allows him to connect with each patient over time.

Taking care of these people, that’s my job. I never worked a day in my life.

When they walk into Nowzaradan’s Bellaire Boulevard office, patients may encounter a camera crew stationed at the door, as Houstonia did when we visited. That’s not much of a surprise, but for many people, Nowzaradan’s prognosis is.

“People come looking for a single solution to their problem, and sometimes the answer is not what they want to hear,” he says. “They think surgery is the solution for everything. And it’s not going to change people’s behavior toward food.”

To some, the words “weight loss surgeon” has a sheen of sleaze, thanks to practitioners who prey on the desperate, hawking a quick fix. But Nowzaradan often makes nothing from the weight-loss surgeries he performs. “Looking at the moral obligation that we’ve got, you see somebody who has no life who could have a life,” he says. “We don’t need to be rich. We do make a living, but we don’t need to worry about making a living out of every patient we see.”

While Nowzaradan is best known for performing gastric-bypass and vertical-sleeve gastrectomy surgeries—his most common procedures, since expanding beyond cardiac surgery—he has spent most of his career as a general surgeon. In fact, he still routinely performs laparoscopic appendectomies and cholecystectomies (removal of the gallbladder), both of which he helped to pioneer. “We stay in the leading edge of surgery,” he adds.

When Nowzaradan first tried his hand at weight-loss surgery in the 1980s, intestinal bypass was in vogue. That gave way to the more predictable gastric-bypass and gastric-sleeve procedures, both of which create a smaller stomach pouch in one way or another. He’s also becoming increasingly fond of less invasive procedures such as gastric plication, which folds the stomach to a capacity of only four to eight ounces, using a single incision and an endoscope. “People can go home the same day, next day, and speed up their recovery,” he says.

Nowzaradan follows up with more surgical intervention once patients have lost the weight: He learned to perform reconstructive skin surgeries as a last step for patients who’ve successfully lost weight. “Plastic surgeons,” he says with a hint of indignation, “wouldn’t touch these people.”

Nowzaradan doesn’t perform weight-loss surgery on everyone who walks in the door. One deciding factor is whether there’s a genetic component to a patient’s heft, which he believes to be the case in about 85 percent of the people who come to him in desperation. The rest? “It seems like eating disorders are becoming more of a factor for people becoming obese,” he says. That, he hopes, they’ll be able to self-correct with therapy, exercise and good nutrition. “Nobody wants to believe that there’s something wrong with their eating habits,” he adds. “They always think it’s something else.”

Getting patients psychological help is imperative, as depression and food dependence can create a vicious cycle. “When we are born, food becomes the center, the first thing that child gets comfort from,” Nowzaradan explains. “Later when people get into stressful situations, they go back to food.” That means that a drastically smaller stomach may take away the patient’s security blanket, which could cause distress, especially for those long accustomed to hiding beneath extra layers of adipose tissue.

Still, many patients are transformed by the surgery, going from what Nowzaradan describes as having “no quality of life” to finding purpose and meaning. His cellphone is full of photos of smiling, average-sized people who used to be obese. And that’s what drives the man who has never wanted to be anything but a surgeon.

As his contemporaries retire, Nowzaradan is working 12 to 14 hours a day, seven days a week, fitting in between 60 and 80 patients each day. And he’s doing it all with an audience, on a TV show now filming season six with no signs of stopping. “Taking care of these people, that’s my job,” he says with a grin. “I never worked a day in my life.”