The football world was stunned when former Denver Broncos wide receiver Demaryius Thomas died suddenly 2021 at just 33 years of age after having a seizure. Doctors now know that Thomas’ untimely death was likely linked to CTE (chronic traumatic encephalopathy), a degenerative brain disease caused by repeated head injuries and concussions.
Thomas was diagnosed with CTE posthumously in July, making him the latest in a long line of former NFL players found to have the disease after their deaths.
CTE can only be conclusively diagnosed after death through an autopsy, meaning many players suffer from its symptoms unchecked during their lives. One study found signs of CTE in 110 out of 111 deceased former NFL players’ brains.
To compile a list of 35 professional football players whose deaths are at least partially attributable to CTE, 24/7 Tempo reviewed profiles of players published by the Concussion Legacy Foundation and articles published by Boston University’s CTE Center. We also reviewed archived news stories about deceased football players published on ESPN, CNN, Sports Illustrated, NPR, and other online sources.
Some common CTE symptoms are confusion, impaired judgment, and extreme mood swings including aggression. Several former players on the CTE list had a history of violent behavior, and some even committed murder or suicide. (These are 33 athletes with famously bad tempers.)
In recent years, suicide has been strongly linked to CTE, with at least 12 of the 35 deceased players having taken their own lives. (These are 37 violent celebrity deaths.)
Aaron Hernandez (1989-2017)
> Position: Tight end
> Years playing in the NFL: 2010-2012
> NFL teams: New England Patriots
> Cause of death: Suicide by hanging
Adrian Robinson (1989-2015)
> Position: Linebacker
> Years playing in the NFL: 2012-2015
> NFL teams: Pittsburgh Steelers, Philadelphia Eagles, Denver Broncos, San Diego Chargers, Washington Redskins
> Cause of death: Suicide by hanging
Andre Waters (1962-2006)
> Position: Defensive back
> Years playing in the NFL: 1984-1995
> NFL teams: Philadelphia Eagles, Arizona Cardinals
> Cause of death: Self-inflicted gunshot wound
Bubba Smith (1945-2011)
> Position: Defensive lineman
> Years playing in the NFL: 1967-1976
> NFL teams: Baltimore Colts, Oakland Raiders, Houston Oilers
> Cause of death: Drug overdose
Chris Henry (1983-2009)
> Position: Wide receiver
> Years playing in the NFL: 2005-2009
> NFL teams: Cincinnati Bengals
> Cause of death: Car accident
Colt Brennan (1983-2021)
> Position: Quarterback
> Years playing in the NFL: 2008-2010
> NFL teams: Washington Redskins, Oakland Raiders
> Cause of death: Drug overdose
Cookie Gilchrist (1935-2011)
> Position: Fullback
> Years playing in the NFL: 1962-1967
> NFL teams: Buffalo Bills, Denver Broncos, Miami Dolphins
> Cause of death: Bladder cancer
Daniel Te’o-Nesheim (1987-2017)
> Position: Linebacker
> Years playing in the NFL: 2010-2013
> NFL teams: Philadelphia Eagles, Tampa Bay Buccaneers
> Cause of death: Lethal mixture of pills and alcohol
Dave Duerson (1960-2011)
> Position: Safety
> Years playing in the NFL: 1983-1993
> NFL teams: Chicago Bears, New York Giants, Phoenix Cardinals
> Cause of death: Self-inflicted gunshot wound
Demaryius Thomas (1987-2021)
> Position: Wide receiver
> Years playing in the NFL: 2010-2019
> NFL teams: Denver Broncos, Houston Texans, New England Patriots, New York Jets
> Cause of death: Seizure
Earl Morrall (1934-2014)
> Position: Quarterback
> Years playing in the NFL: 1956-1976
> NFL teams: San Francisco 49ers, Pittsburgh Steelers, Detroit Lions, New York Giants, Baltimore Colts, Miami Dolphins
> Cause of death: Complications from Parkinson’s disease
Frank Gifford (1930-2015)
> Position: Running back
> Years playing in the NFL: 1952-1960, 1962-1964
> NFL teams: New York Giants
> Cause of death: Natural causes
Fred McNeill (1952-2015)
> Position: Linebacker
> Years playing in the NFL: 1974-1985
> NFL teams: Minnesota Vikings
> Cause of death: Lou Gehrig’s disease
Greg Clark (1972-2021)
> Position: Tide end
> Years playing in the NFL: 1997-2001
> NFL teams: San Francisco 49ers
> Cause of death: Self-inflicted gunshot wound
John Grimsley (1962-2008)
> Position: Linebacker
> Years playing in the NFL: 1984-1993
> NFL teams: Houston Oilers, Miami Dolphins
> Cause of death: Accidental gunshot wound
John Mackey (1941-2011)
> Position: Tight end
> Years playing in the NFL: 1963-1972
> NFL teams: Baltimore Colts, San Diego Chargers
> Cause of death: Dementia
Jovan Belcher (1987-2012)
> Position: Linebacker
> Years playing in the NFL: 2009-2012
> NFL teams: Kansas City Chiefs
> Cause of death: Self-inflicted gunshot wound
Junior Seau (1969-2012)
> Position: Linebacker
> Years playing in the NFL: 1990-2009
> NFL teams: San Diego Chargers, Miami Dolphins, New England Patriots
> Cause of death: Self-inflicted gunshot wound
Justin Strzelczyk (1968-2004)
> Position: Offensive tackle
> Years playing in the NFL: 1990-1998
> NFL teams: Pittsburgh Steelers
> Cause of death: Car crash
Ken Stabler (1945-2015)
> Position: Quarterback
> Years playing in the NFL: 1968-1984
> NFL teams: Oakland Raiders, Minnesota Vikings, Houston Oilers, New Orleans Saints
> Cause of death: Colon cancer
Kevin Turner (1969-2016)
> Position: Fullback
> Years playing in the NFL: 1992-1999
> NFL teams: New England Patriots, Philadelphia Eagles
> Cause of death: Lou Gehrig’s disease
Mike Webster (1952-2002)
> Position: Center
> Years playing in the NFL: 1974-1990
> NFL teams: Pittsburgh Steelers and Kansas City Chiefs
> Cause of death: Heart attack
Mosi Tatupu (1955-2010)
> Position: Running back
> Years playing in the NFL: 1978-1991
> NFL teams: New England Patriots, Los Angeles Rams
> Cause of death: Heart attack
Ollie Matson (1930-2011)
> Position: Running back
> Years playing in the NFL: 1952-1966
> NFL teams: Chicago Cardinals, Los Angeles Rams, Detroit Lions, Philadelphia Eagles
> Cause of death: Complications of dementia
Paul Oliver (1984-2013)
> Position: Safety
> Years playing in the NFL: 2007-2011
> NFL teams: San Diego Chargers, New Orleans Saints
> Cause of death: Self-inflicted gunshot wound
Phillip Adams (1988-2021)
> Position: Cornerback
> Years playing in the NFL: 2010-2015
> NFL teams: San Francisco 49ers, New England Patriots, Seattle Seahawks, Oakland Raiders, New York Jets, Atlanta Falcons
> Cause of death: Murder-suicide
Ralph Wenzel (1943-2012)
> Position: Guard
> Years playing in the NFL: 1966-1973
> NFL teams: Pittsburgh Steelers, San Diego Chargers
> Cause of death: Complications of dementia
Ray Easterling (1949-2012)
> Position: Safety
> Years playing in the NFL: 1972-1979
> NFL teams: Atlanta Falcons
> Cause of death: Self-inflicted gunshot wound
Rob Lytle (1954-2010)
> Position: Running back
> Years playing in the NFL: 1977-1983
> NFL teams: Denver Broncos
> Cause of death: Heart attack
Shane Dronett (1971-2009)
> Position: Defensive lineman
> Years playing in the NFL: 1992-2002
> NFL teams: Denver Broncos, Detroit Lions, Atlanta Falcons
> Cause of death: Self-inflicted gunshot wound
Terry Long (1959-2005)
> Position: Guard
> Years playing in the NFL: 1984-1991
> NFL teams: Pittsburgh Steelers
> Cause of death: Suicide by drinking a gallon of antifreeze
Tom McHale (1963-2008)
> Position: Offensive guard
> Years playing in the NFL: 1987-1995
> NFL teams: Tampa Bay Buccaneers, Philadelphia Eagles, Miami Dolphins
> Cause of death: Drug overdose
Tommy Nobis (1943-2017)
> Position: Linebacker
> Years playing in the NFL: 1966-1976
> NFL teams: Atlanta Falcons
> Cause of death: Unspecified extended illness
Tyler Sash (1988-2015)
> Position: Safety
> Years playing in the NFL: 2011-2012
> NFL teams: New York Giants
> Cause of death: Accidental overdose of painkillers
Vincent Jackson (1983-2021)
> Position: Wide receiver
> Years playing in the NFL: 2005-2016
> NFL teams: San Diego Chargers, Tampa Bay Buccaneers
> Cause of death: Chronic alcohol use