Football and Brain Injuries: What You Need to Know

The dangers of professional football is a hot topic. Studies have found high rates of concussions, traumatic brain injuries, and a serious brain disorder called chronic traumatic encephalopathy (CTE) in former players. These injuries can have terribly debilitating effects. For the 2017-2018 football season, the NFL changed certain rules to make play safer, but how effective have the rule changes been?  And what are the implications for children, teenagers, and college students who play football?

What is a Concussion?

Concussions occur when a collision causes the brain to hit the inside of the skull. The greater the force of the impact, the more severe the concussion. Symptoms can include disorientation, memory problems, headaches, fogginess, and loss of consciousness. After suffering from one concussion, a person (especially an athlete) is much more likely to suffer from a second one after another injury. A second concussion often comes with symptoms that last longer than the first. The CDC reports that having more than one concussion can cause depression, anxiety, aggression, personality changes, and an increased risk of Alzheimer’s, Parkinson’s, CTE, and other brain disorders.[1]

How Can You Prevent a Concussion?

Sports will always have risks, but there are many ways to prevent serious concussions. Helmets and mouth guards are widely used but there is no evidence that they help prevent concussions. In contrast, there is convincing evidence that reducing or eliminating body checks or tackling in rough sports like hockey and football will help prevent concussions.[2]

What is CTE?

CTE is a brain disorder that is caused by repeated head injuries. These brain changes progress and worsen over time, and may not be noticed for months, years, or decades after the last brain injury.[3] Common symptoms include memory loss, impaired judgment, aggression, and depression. Some of former athletes with CTE have committed suicide or murder. CTE is most often found in athletes who have experienced repeated head injuries, such as former boxers, hockey players, and football players.

What’s in the News?

One famous example of CTE is former NFL star Aaron Hernandez. Hernandez committed suicide in prison where he was serving time for murder. The autopsy results revealed that he had a severe case of CTE – the worst case ever reported on such a young man (Hernandez was only 27 years old). Doctors categorize CTE in four stages, with Stage 4 CTE as the worst. Hernandez was diagnosed with Stage 3 CTE, which causes memory loss, damaged thinking, as well as changes in behavior and impaired judgment.[3,4,5]

In September 2017, President Trump tweeted that the NFL is “ruining the game” because the league’s safety restrictions and rules make the game less enjoyable to watch. This raised questions about whether football fans want to watch more violent games, regardless of players’ safety and health.[4] How common is CTE and is the NFL overreacting?

A study published in the Journal of American Medical Association (JAMA) in July 2017 found that among 202 deceased former football players, 177 of them were diagnosed with CTE.[6] There were 111 former NFL players in the study, and 110 of them were diagnosed with CTE. The results are not typical of all former football players, since all the bodies studied were donated by family members who wanted to know if their loved ones had CTE when they died.  However, it does show that there are many former football players that have developed CTE.

There is only one confirmed case where CTE was accurately diagnosed in a living person. Fred McNeil, a former NFL player who retired in 1985, had an experimental brain scan in 2012.[7] Two years later, he had impaired movement and difficulty performing everyday tasks, such as buttoning his shirt, tying his shoes, and feeding himself. His condition worsened and he was confined to a nursing home. After his death at the age of 63, the researchers studied his brain. They were shocked to find that the abnormalities of earlier brain scans closely matched what they saw in the brain tissue. The scientists believe that similar brain scans may one day be used to diagnose CTE in living people, but it is not clear whether scanning would make any difference in a person’s life because there is no cure for the condition. (Here is the link to the study).

What About Children and Teens Who Play Football?

The NFL has been criticized for hiding the short- and long-term risks of concussions and repeated head injuries from players and the public. Studies now reveal that large numbers of football players have suffered from the relaxed enforcement of safety rules.

For example, researchers at Virginia Tech found that football risks start at an early age.[8] Their study found that young children take high-force hits to the head. The researchers observed 9- to 12-year-old players and found that about 8% of head impacts were high-magnitude, defined as greater than 40 times the force of gravity. These impacts were more likely to occur in competitive games rather than during practices. Quarterbacks, running backs, and linebackers were all at greater risk. These findings confirm parents’ concerns about the risks of playing football at a young age.

Another study found that dangers are much greater when players start before the age of 12, because they are twice as likely to develop mood and behavior problems later in life.[9] For several years, researchers have been warning about the health risks of football, especially for children, and as a result participation in tackle football for 6-12 year olds has dropped by almost 20% since 2009. In response, USA Football introduced a new version of football called “rookie tackle,” which aims to decrease the physical toll on young children. Even with this safer version of the game, however, researchers and parents still don’t know if children are safe enough.

The New NFL Rules

To make play safer for NFL player, the league has changed several rules. They have moved kickoffs from the 30 yard line to the 35 yard line and touchbacks from the 20 yard line to the 25 yard line.[10] A kickoff is when the defending or kicking team kicks the ball to the other  team at the start of a half or after a score. A touchback is when the offensive or receiving team takes a knee in the end zone after a kickoff instead of running to gain yards. The teams are running towards each other on this type of play, so this rule shortens the distance between the kicking team and the receiving team. Since players gain a lot of speed as they run at each other from across the field, the shorter distances are less dangerous. The NFL plans to also reduce injuries by continuing to disqualify players who exhibit poor sportsmanship and dangerous conduct.

Another new rule is the crown-of-the-helmet rule (CHR), which penalizes defensive players or offensive ball carriers who initiate contact with the top of their helmet. This type of play happens when a player uses his head to hit another player’s head, which is very dangerous for both players. There is now a 15-yard penalty for this type of hit. CHR reduces the weekly probability of defensive player concussions from 29 to 32%.[11] It reduces the probability of all head and neck injuries by 34%. The downside of this rule is that players are more likely to tackle the lower body, which increases risk of serious lower body injuries.

As of December 2017, the NFL made several changes to its concussion protocol.[12] Prior to the change, if a player left the field with a possible concussion, he had to stay out of the game while he was being evaluated. If he was diagnosed with a concussion, he would continue to be benched for the rest of the game and for as long as it took for a doctor to clear him for play. After incidents in December, the NFL changed the rules in an attempt to better protect the players. These new rules include having an unaffiliated neurotrauma consultant (UNC) for all games, evaluating any player who seems to lack motor stability or balance, and re-evaluating any player who had been evaluated for a concussion during a game within 24 hours of the initial evaluation. Having the decision made by an expert who is not working for either team is a good way to try to better protect player safety.

It will be some time before we know how effective these new rules are. Injuries are still very common as shown in this list of all current NFL injuries.

Best Practice Guidelines

To reduce the number of sports-related concussions, follow these safety rules:

Rapid screening: On the sideline, players should be evaluated for 3 signs: loss of consciousness, stiff body or balance problems. Any of these signs are dangerous and players with any of the three signs must be immediately removed from the game and brought to a hospital. For players without severe signs, a coach or athletic trainer can perform a brief screening tool, such as SCAT5 (Sports Concussion Assessment Tool version 5).

No return to play: A player with a diagnosed concussion should not return to play the same day.

Re-evaluation: A player must be evaluated by a doctor after the first hit and should be re-evaluated for worsening symptoms in the following days. When an athlete is diagnosed with a concussion, he or she should have a complete neurological exam and cognitive testing.

Rest: Rest decreases the demands on the brain, which allows the brain to heal after an injury. Complete rest includes both physical and mental rest (that means no school work, reading, or TV). After a full 24-48 hours of rest, athletes can become gradually become more active.

Gradual return to sport: It may take 10-14 days in adults and 4 weeks in youth to fully recover and be free of any symptoms. The athlete should start with light activity that does not cause any symptoms, and gradually increase activity. For example, the athlete may try light walking instead of running to limit any risk of further injury. Light walking is defined as walking slowly enough to not break a sweat or have any shortness of breath. If more intense activity like running causes symptoms, the athlete should stop and return to light walking.

Screen for mental health or learning disabilities: Concussions increase the risk for developing mental health problems such as anxiety and depression. And, those who previously had any mental health conditions may take longer to recover after a concussion. In addition, those with ADHD or learning disabilities may have difficulty with school work after a concussion. Before an athlete starts a sport, a doctor must sign off that they can participate. In addition to a physical exam, athletes should be screened for behavioral or learning issues.

Bottom Line

There are many hidden dangers of contact sports like football, but new rules emphasizing safety over entertainment may help to reduce risks.

All articles are reviewed and approved by Dr. Diana Zuckerman and other senior staff.


  1. Centers for Disease Control and Prevention. (2017). Traumatic Brain Injury & Concussion. Retrieved from Accessed on October 23, 2017.
  2. McCrory, P., Meeuwisse, W., Dvorak J., et al. (2017). Consensus Statement on Concussion in Sport – the 5th International Conference on Concussion in Sport Held in Berlin October, 2016. British Journal of Sports Medicine. Published Online First: 26 April 2017. doi: 10.1136/bjsports-2017-097699. Retrieved from Accessed on October 27, 2017.
  3. Boston University Research CTE Center. (2017). Frequently Asked Questions about CTE. Retrieved from Accessed on October 27, 2017.
  4. Loria, K. (2017). Trump Suggested the NFL is Being Ruined Now That It’s Addressing Brain Injuries – Here’s What Collisions Do To Players. Business Insider. Retrieved from Accessed on October 23, 2017.
  5. Belson, K. (2017). Aaron Hernandez Had Severe CTE When He Died at Age 27. New York Times. Retrieved from Accessed on October 23, 2017.
  6. Mez, J., Daneshvar, D., and Kiernan, P. (2017). Clinicopathological Evaluation of Chronic Traumatic Encephalopathy in Players of American Football. JAMA. 318(4):360-370. doi:10.1001/jama.2017.8334.
  7. Kounang, N. (2017). Ex-NFL Player Confirmed as 1st Case of CTE in Living Patient. CNN. Retrieved from Accessed on November 27, 2017.
  8. Thorbecke, C. (2017). Children Who Play Football May Take More Hits to the Head Than Originally Thought, Study Finds. ABC News. Retrieved from Accessed on November 1, 2017.
  9. Maese, R. (2017). Study Shows Playing Football Before Age 12 Can Lead to Mood and Behavior Issues. Washington Post. Retrieved from Accessed on November 1, 2017.
  10. National Football League. (2017). 2017 Rules Changes and Points of Emphasis. NFL Operations. Retrieved from Accessed on November 1, 2017.
  11. Hanson, A., Jolly, N., and Peterson, J. (2017). Safety Regulation in Professional Football: Empirical Evidence of Intended and Unintended Consequences. Journal of Health Economics. 53(1): 87-99. Retrieved from Accessed on November 1, 2017.
  12. France-Presse, A. (2017). N.F.L. Changes Concussion Protocol. New York Times. Retrieved from Accessed on January 17, 2018.