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CTE Discoverer: We Shouldn’t Be Surprised That Aaron Hernandez Had CTE

NFL: DEC 02 Patriots at DolphinsNFL: DEC 02 Patriots at Dolphins
New England Patriots tight end Aaron Hernandez (81) runs against the Miami Dolphins in New England's 23-16 victory at Sun Life Stadium, Miami, Florida. Icon Sports Wire Corbis via Getty Images

Last week, the football world was shocked to learn that former New England Patriots star tight end Aaron Hernandez had stage 3 Chronic Traumatic Encephalopathy (CTE) when he took his own life in his prison cell. I, on the other hand, was not shocked.

Hernandez was only 27 at the time of his death, and had only played three seasons in the NFL. Outbursts of violent behavior, however, began during his freshman year in college and continued until he was arrested for murder in 2013. Hernandez’s family and friends always wondered how a boy who never got into any kind of trouble, who had a reputation for being a good kid from a good family, could take such a dark turn. I believe much of that question was answered with the CTE diagnosis. Hernandez’s final outcome was a result of his cumulative exposure to trauma—beginning from his childhood days of football, including every blow he received to his head from the very first game he played to the very last game he played.

When I discovered CTE in the brains of NFL players Mike Webster, Terry Long, Andre Waters, and pro wrestler Chris Benoit, among others, I researched the medical literature as far back as the writings of Hippocrates around 400 B.C. Centuries ago, science confirmed that there is no safe blow to the human head. The more forceful the blow is, and the more repetitive the blows are, the greater the likelihood of brain damage.

We now know that all it takes to cause permanent brain damage in a child is one concussion, with or without a helmet. Even with or without a documented concussion, all it may take for a child to suffer brain damage is one season of playing football. Helmets do not and cannot eliminate sub-concussive and concussive injuries to the brain. Football apologists may dismiss these findings and may grudgingly acknowledge the danger of brain damage from football, but only in those who played in the NFL for a very long time, decades ago, wanting to believe that football is now safer due to the changes made. The Hernandez diagnosis further shows that children who play football and other contact sports are indeed at great risk.

CTE is only one disease in a broad spectrum of diseases caused by brain damage from contact sports. Medical studies and research have shown that if a child suffers brain damage while playing contact sports, that child may manifest markedly increased risks for the following as that child grows to become an adult: dying before the age of 42, especially from violent causes; suffering diminishing intelligence; losing the ability to maintain long attention spans and acquire new knowledge; dropping out of high school or college and not attaining high levels of education; losing impulse and mood control and exhibiting impulsive behavior; engaging in violent and criminal behavior; manifesting disinhibition, including social and sexual improprieties; drug addiction and alcoholism; suffering from major psychiatric illnesses, including major depression, committing suicide, and engaging in self-destructive behavior; suffering from memory impairment; and losing other cognitive functions, including engaging in complex thinking and other executive functions. Such a child is more likely to be less gainfully employed as an adult, and is more likely to become a welfare or disability recipient.


In 1957, 11 years before I was born, the American Academy of Pediatrics advised that “body-contact sports, particularly tackle football and boxing, are considered to have no place in programs for children” under the age of 12 years old. In 2011, the same American Academy of Pediatrics together with the Canadian Pediatric Society, advised that physicians vigorously oppose boxing in children and encourage children to participate in alternative sports in which intentional blows to the head are not central to the sport. In 2017, given what we know now, there is no justifiable reason whatsoever for any child younger than the age of 18 years to engage in the high-impact, high-contact sports in which intentional blows to the head are intrinsic to the play. I believe this truth should be self-evident, yet some still want to close their eyes to the truth. As the Hernandez story made headlines, the President of the United States said that penalties for hard hits were ruining the game of football. It seems we still have a long way to go.

A recent scientific paper has reported that the lost productivity caused by these types of brain damage negatively impacts the United States economy and GDP to the tune of $1.1 trillion over 30 years. This is lost productivity only—we have not factored in the costs and impacts of health care and health maintenance for these children who have suffered brain damage. This impacts all of us as a society, for we are all members of one another. What happens to one of us happens to all of us. I strongly advise every parent in America to read the book Truth Doesn’t Have a Side. These are inconvenient truths, but we cannot and should not develop alternative truths because of the inconvenience, difficulty, and pain of the one truth. In our lives, there can only be one truth.

Bennet Omalu is a forensic pathologist/neuropathologist/epidemiologist, San Joaquin County Sheriff-Coroner/Chief Medical Examiner, and clinical professor of Medical Pathology and Laboratory Medicine at the University of California, Davis.