Tweet   Blair River, the 575-pound spokesman for Arizona’s Heart Attack Grill restaurant, died on Tuesday. He was 29.  At 6 feet 8 inches, River was a giant ambassador for the high-calorie eatery, and he was remembered fondly by the restaurant's founder. "We all have a very, very brief time on this earth, and the measure of a man is how he leaves the world after he's been here, and I can tell you More.. Blair River was my friend," Jon Basso told KSAZ, a Phoenix TV station. The cause of death remains unknown, but those close to River believe it was the result of a bout with the flu that gave way to pneumonia, The Arizona Republic reports. Here are five facts on the late Blair River, compliments of Surge Desk. 1. He was the Heart Attack Grill's YouTube star Here is River promoting the restaurant in a commercial:2. He was a wrestling champion River was the Arizona state heavyweight wrestling champion in 1999 during his senior year at Payson High School. 3. Modeling was his side gig River earned $100 an hour modeling for the Heart Attack Grill when he wasn't working as a financial adviser at the University of Phoenix. 4. He was a big guy, to say the least River's shirt size was a massive 6XL, and his pants size measured at 56 inches. 5. He tried to lose weight — sometimes River's diet history was sort of a mixed bag. At times he tried trimming down through portion control and even auditioned for NBC's "The Biggest Loser," but he was never chosen. In the end, though, he just loved food. "I'm going ... to try the Heart Attack Grill diet," he jokingly told The Arizona Republic in 2010. "I don't know if it will help me lose weight."