Understanding MASH, the Rare Liver Disease Dan Marino Has Been Diagnosed With

Former Miami Dolphins quarterback Dan Marino is opening up about his health in the hope that more people will stay on top of their routine exams. The 64-year-old says that one of those annual visits to his doctor's office may have saved his life in 2007, after he received some surprising news.

Marino shares how he was diagnosed with a rare liver disease known as metabolic dysfunction-associated steatohepatitis (MASH) that required him to completely change his life.

Nearly two decades later, the former footballer is opening up about everything he's learned since his diagnosis, and using his experience to remind people of the importance of not only prioritizing their health, but also of the value of having a village behind you when you receive a life-changing diagnosis.

You can read more about Marino's story, as well as his health prognosis, below.

Marino opened up to People magazine about his diagnosis in a September 2025 interview, after he publicly went on the record about his liver disease by taking part in the Unordinary Stories campaign being sponsored by Novo Nordisk.

During the interview, he explained how he had very few symptoms prior to be diagnosed as part of a regular screening in 2007, and at the time his chief complain was feeling "a little bit fatigued," which he credited to his post-retirement routine.

“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," he admitted. Fortunately, the doctors were quick to explain that the condition could be reversable with lifestyle changes, which Marino said included losing weight and exercising.

Marino said his family and friends were quick to jump in and help him, and his wife helps him juggle his schedule while his friends train with him at the gym.

Metabolic dysfunction-associated steatohepatitis used to go by the term nonalcoholic fatty liver disease. According to the U.S. Food and Drug Administration (USDA), MASH is serious liver disease that is caused by excessive fat buildup in the liver, which leads to scarring and inflammation.

This condition appears to be caused by other pre-existing conditions, like type 2 diabetes, obesity, high LDL-cholesterol, and high triglycerides. When left untreated, MASH can cause additional complications.

While Marino sounds like he was able to get his MASH under control, those who don't could end up with more significant health issues, including worsening liver function, cancer, cirrhosis (a severe form of liver scarring), the need for a liver transplant, and even death.

Unfortunately, many people have no symptoms of this disease to begin with, which is one of the reasons why Marino wants to raise awareness about the importance of health screenings.

That being said, some symptoms can include unintentional or unexplained weight loss, muscle weakness, and fatigue, although the USDA notes that most people don't experience any unusual signs that something is wrong until they are suffering from severe liver damage.