At least 25% of former NFL players who died between 2016-2021 had CTE, study finds

A study published in The BMJ reveals that at least 25% of former NFL players who died between 2016 and 2021 had chronic traumatic encephalopathy (CTE). Researchers analyzed 235 donated brains from a cohort of 878 deceased players, finding CTE in 215 cases. Lead author Dr. Daniel Daneshvar notes that cumulative head impacts across youth, high school, and college levels drive this risk. While the NFL highlights its safety initiatives, experts urge lower-level leagues to adopt strict contact practice limits to reduce head trauma.

CTE prevalence among NFL players

• ▪The study of deceased NFL players calculated a maximum possible CTE prevalence of approximately 97% if all players except the 20 with cleared diagnoses had the disease.
• ▪A study published in The BMJ on August 25, 2026, found that at least 25% of former NFL players who died between 2016 and 2021 had chronic traumatic encephalopathy (CTE).
• ▪The study's lead author, Dr. Daniel Daneshvar, stated that the true rate of CTE at death among NFL players lies somewhere between the 25% minimum and 97% maximum estimates.

Brain donation research methodology

• ▪To establish a baseline, researchers compiled a denominator list of 1,712 deceased players who had appeared in at least one NFL game since 1949 using CDC death certificates.
• ▪Of the more than 330 NFL players who died between 2008 and 2021 and whose brains were donated to the UNITE Brain Bank at Boston University, 93% were diagnosed with CTE.
• ▪Out of 878 former NFL players who died between 2016 and 2021, families donated 235 brains to researchers, and 215 of those donated brains were diagnosed with CTE.

Repeated head impact causation

• ▪Dr. Daniel Daneshvar stated that the cumulative head impacts leading to CTE risk primarily occur at the youth, high school, and collegiate levels rather than solely in the NFL.
• ▪Dr. Daniel Daneshvar noted that former NFL players experience a rate of death from neurodegenerative diseases that is approximately four times higher than the general population.

Dementia correlation with CTE

• ▪The study found that more than 90% of brain donors diagnosed with Stage IV CTE, the most advanced stage, had also been clinically diagnosed with dementia during their lives.
• ▪The correlation between dementia and lower stages of CTE was unclear, as 40% of the donated brains that were entirely free of CTE were also clinically diagnosed with dementia.
• ▪Neuroepidemiologist Rachel Grashow expressed concern that public discussions about CTE create hopelessness, potentially discouraging living former players from seeking treatment for treatable conditions like sleep apnea.

NFL practice contact limits

• ▪An NFL spokesperson stated that the league continuously strives to make football safer by implementing strategies to reduce concussions and head impacts while providing health resources to former players.
• ▪Dr. Daniel Daneshvar advocated for propagating NFL-style contact limits, which restrict contact practices to less than once per week, to collegiate, high school, and youth sports levels.
• ▪The NFL limited the number of contact practices during the season in its 2011 Collective Bargaining Agreement, and the Ivy League banned full-contact tackling in practices in 2016.

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