In 2025, J.J. Spaun is looking to enter another echelon of stardom on the PGA Tour.
The Los Angeles native had already jumped into the top 25 of the Official World Golf Rankings heading into the 2025 U.S. Open and was in search of his first PGA Tour win since the Valero Texas Open in April 2022.
Spaun entered the spotlight this year thanks to a second-place finish at The Players Championship, but that spotlight got even brighter after he made an improbably comeback, conquering Oakmont and winning the U.S. Open.
With Spaun in the spotlight, fans have learned more about the unique health challenges he has navigated since turning pro, and how he used an initial diabetes misdiagnosis to become an advocate for diabetes research and the continued search for a cure.
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J.J. Spaun diabetes misdiagnosis
In 2018, Spaun sought medical counsel as he began to feel run down and was losing weight. Doctors misdiagnosed him with Type 2 diabetes and treated him accordingly, but there were no improvements in his physical health, and his game continued to suffer.
“It was going up, and then all of a sudden this gets thrown at me. It was kinda weird; I didn’t want it to mess with me mentally, but it was a big change,” Spaun said of the misdiagnosis during a 2022 podcast appearance.
After missing the cut at the 2021 Valspar, Spaun learned he was misdiagnosed and that he actually has Type 1 diabetes, not Type 2. While he did not completely attribute his struggles to the misdiagnosis, Spaun considered it a contributing factor to coming up short and temporarily losing his PGA Tour card.
In the time since, Spaun has dedicated many of his resources to diabetes research, including large donations to Breakthrough T1D (formerly JDRF), an organization dedicated to finding a cure for Type 1 diabetes.
Spaun mentioned that in the three years after his misdiagnosis, he lost more than 50 pounds. He has since regained his healthy weight and takes several measures to monitor his blood sugar on the course.
In a 2022 interview with the PGA, Spaun explained that he wears a blood sugar monitor on the course that is "part of my golf bag now." High numbers can impact his vision and fatigue, while low numbers can make him feel lightheaded and shaky.
Spaun's success on the PGA Tour has made him a model of success for those living with Type 1 diabetes worldwide, with his story serving as a reminder that a diabetes diagnosis does not necessarily have to hold you back.
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Differences between Type 1 and Type 2 diabetes
Type 1 and Type 2 diabetes come from different causes, as outlined by the University of Virginia. Here is how they differ.
In diabetes type 1, the pancreas does not make insulin, because the body’s immune system attacks the islet cells in the pancreas that make insulin.
In diabetes type 2, the pancreas makes less insulin than used to, and your body becomes resistant to insulin. This means your body has insulin, but stops being able to use it.
Type 1 diabetes is an autoimmune disease, but the reasons why the immune system attacks the pancreatic islet cells are unknown. Some hypothesized factors to trigger such a reaction are genes, viruses, foods, and chemicals.
Type 2 diabetes is a common disease, and the insulin resistance that causes it is having too much body fat. Type 2 most often occurs in people over 45 or in younger people with obesity or a genetic predisposition.