As a neurologist and former football fan, I had a vague awareness of the effects of cumulative trauma to the brain. A recent lecture by Robert Stern of Boston University, a leading researcher in this field, has awakened my concern about football’s effect on the brains of our young players.

I was aware that some football players later in life develop a progressive neurologic condition with memory loss and erratic and violent behavior, leading to death. I did not know that they have a specific neurologic disease, chronic traumatic encephalopathy, with specific neuropathology and clinical features, and that this untreatable disease is caused by the long-term cumulative effect of many blows to the head.

Research has shown that football hits to the head cause an acceleration/deceleration blow to the brain of up to 20 times the force of gravity, and players receive this injury many times during practices and games. Football linemen may have 1,000 to 1,500 subconcussive impacts in a season.

The cumulative number of hits and the age when kids begin to play tackle football are the best predictors of risk for developing CTE. Players who bang heads on nearly every play, youngsters who start playing before full brain maturation and those who continue to play in college and the pros are most at risk. Autopsy studies have shown the beginnings of the irreversible, progressive disease as early as age 20.

Concussion is a separate issue, and focusing on concussion alone does nothing to reduce the risk of CTE from repetitive subconcussive head blows.

Players and parents should take these facts into account when deciding if football is an appropriate sport for them to play. Football fans should be aware that they are supporting a sport that results in a tragic downhill course leading to death in a number of players.

Richard L. Sullivan, M.D.

Cape Elizabeth