New Study Estimates 75% of Dead Ex-NFL Players Had CTE

Researchers at Boston University published a new analysis in JAMA Network Open estimating that 74.5% of former NFL players who died between 2008 and 2023 had chronic traumatic encephalopathy. The study represents the most recent large-scale assessment of CTE prevalence in the sport.

CTE is a degenerative brain disease associated with repeated head impacts. It can only be confirmed through autopsy after a player dies. While the condition appears in other athletes, first responders, and military personnel, the new data shows a significantly higher rate among deceased NFL athletes compared to the general population.

Lead author Julia Gallini stated that CTE is found in less than 1% of donors to community brain banks. She described the estimated 75% prevalence among NFL players as a concerning figure that suggests a need for increased efforts to support families and diagnose symptoms during a player's life.

The new findings follow an earlier report released in August 2026. That previous study estimated CTE prevalence between 25% and 98% for players who died from 2016 to 2021. Boston University noted that the wide range in the earlier data reflected uncertainty about whether brain donors represented the full NFL population. Donors often present with cognitive symptoms, creating a selection bias that can skew results.

To address this bias, the new analysis examined 387 deceased former players. Researchers found CTE in 362 of those individuals. They calculated that former players with cognitive symptoms were five times more likely to donate their brains to science. By applying this selection ratio, the team adjusted the 94% prevalence observed in donors down to the 74.5% overall estimate.

The study covers only players who have already died. It does not provide a prediction for how many living former players or current active athletes have the condition. Matt Hasselbeck, a former NFL quarterback and ambassador for the research, said the data should guide safety improvements. He stated that the league must learn from the suffering of those who built the game to protect the next generation of players.

The NFL responded by saying it continuously strives to make football safer. The league cited improved equipment and rule changes designed to reduce concussions and head impacts. It also stated that it remains committed to providing the NFL community with resources for physical and mental well-being. The NFL Players Association called the study critical for understanding long-term health effects and reaffirmed its commitment to supporting scientific research and player care.