Dolphins Legend Dan Marino Health Diagnosis Revealed on His 64th Birthday

Dan Marino might be the most beloved and recognized legend for the Miami Dolphins, and September 15 is his birthday.

On the day he turned 64 came the revelation of a disease he has been dealing with for years.

Marino, arguably the greatest passer in NFL history, sat down with PEOPLE in a new interview where he revealed new and intimate details about being diagnosed with a form of liver disease.

Marino revealed that back in 2007, he went for a routine checkup, where he told doctors that he was feeling "a little fatigued." The Hall of Famer remembers thinking that his exhaustion had to do with his not working out like he had when he was playing football.

"I wasn't really working out as much as I should — because I used to work out when I played all the time and I kind of got away from that a little bit," Marino told PEOPLE.

Despite the belief that his working out stopped and led to him feeling winded, Marino revealed that the doctors told him he had a disease called MASH.

“Those are the things I kind of noticed,” Marino said. “Then they told me I had a fatty liver. I had MASH.”

"Metabolic dysfunction-associated steatohepatitis (MASH) happens because you have excess fat cells in your liver. This condition once was called nonalcoholic fatty liver disease (NASH). Excess fat cells cause chronic inflammation that can lead to worsening liver damage. MASH is often associated with having overweight, high blood lipids and high blood sugar," per the Cleveland Clinic.

Though the diagnosis sounds serious, it is something that is very treatable and can be reversed. Marino revealed the main thing doctors told him was that losing weight would aid in reversing the disease.

"You gotta work out. You got to lose weight," Marino recounts the doctors saying to him.

Marino began to get to work right away, enlisting the help of former Dolphins teammate Terry Kirby, who helps train the former quarterback at a nearby gym. Marino's wife Claire, also joined in on nightly walks and bike rides.

Despite the scary diagnosis, Marino also revealed that his strict diet and working out helped to keep the diagnosis in check. He stopped eating pizza, candy, and ice cream, and switched to a doctor-recommended Mediterranean diet.

Marino said that he gets checkups every year and has been putting in the work to ensure his MASH diagnosis does not get worse. Between exercise, diet, and annual checkups, his prognosis is getting "better."

Despite his having been diagnosed with MASH some years ago, Marino chose his birthday to reveal his diagnosis to spread awareness and to offer a message of hope for those who may have been diagnosed with the same disease.

"If you get diagnosed with fatty liver and MASH, doing the things you need to do, like I talked about — diet, working out — and staying consistent with it, that's what our message really is," Marino stated.

Marino, who was inducted into the Pro Football Hall of Fame in 2005, serves as special advisor to Dolphins vice chairman/ president/CEO Tom Garfinkel.

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