Professional athletes are known to get injured throughout the season, however not much is known about the long-term effects of years of all that physical strain.
A Harvard study published Friday in JAMA found some chilling evidence on these effects, including how playing a specific sport may affect health outcomes.
Most importantly, researchers found that National Football League players had significantly higher mortality rates from all causes, driven by higher rates of degenerative brain and heart mortality, compared to Major League Baseball players.
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To determine this, researchers looked at more than 6,000 professional athletes who competed in at least five seasons in the NFL or MLB, according to the Associated Press. Of the athletes, who were all born prior to 1965, 517 died at an average age of 60 among NFL players and 431 MLB players died at age 67 on average.
The AP noted:
Brain diseases caused or contributed to 39 NFL deaths compared with 16 deaths among baseball players. That amounts to a nearly three times greater risk for NFL players, results that echo an earlier study comparing brain disease deaths in NFL players with the general population. Heart disease caused or contributed to 498 deaths among NFL players, more than double the 225 deaths among the baseball group.
The researchers reportedly theorize football players could be more affected because they tend to have longer careers, but more research on the matter is needed.
Learn more about this study from the Associated Press here.