CTE cannot be completely prevented as long as someone participates in activities involving repeated head impacts, but the risk can be significantly reduced. The core strategy is straightforward: minimize the total number of hits your brain absorbs over a lifetime. That includes concussions, but also the thousands of smaller, subconcussive impacts that never produce obvious symptoms. Research from Boston University’s CTE Center found the disease in 345 of 376 former NFL players studied (91.7%), compared to just 0.6% in a general population sample, underscoring that cumulative head trauma exposure is the primary driver.
Why Subconcussive Hits Matter Most
Most discussions about brain injury focus on concussions, but CTE appears to be driven largely by repeated smaller impacts that fly under the radar. Each hit doesn’t need to cause symptoms to do damage. When the brain absorbs force, the structural proteins that stabilize connections inside nerve cells can become chemically altered, losing their ability to do their job. Over hundreds or thousands of impacts, this damage accumulates faster than the brain can repair it.
The damage tends to concentrate in the brain’s grooves and folds, where mechanical stress is highest during an impact. Nerve fibers can stretch and tear at a microscopic level, and cell membranes can develop tiny holes. None of this shows up on a sideline concussion test. A player can take dozens of these hits in a single practice without ever feeling “off,” yet each one contributes to the long-term toll. This is why prevention strategies focus on reducing total hit exposure, not just avoiding diagnosed concussions.
Limit Years of Contact Sport Exposure
The single most effective way to lower CTE risk is to reduce the number of years spent in full-contact sports. Among football players, carrying a specific genetic risk factor for brain disease had roughly the same effect on CTE severity as playing more than seven years of football. That comparison puts the weight of cumulative exposure into perspective: the longer the career, the greater the risk, in a way that compounds over time.
For parents, this means delaying full-contact participation matters. U.S. Soccer adopted guidelines prohibiting heading for players under 10 and limiting those aged 11 to 13 to 15 to 20 headers per week. Similar logic applies to tackle football, where organizations like the Concussion Legacy Foundation recommend flag football through age 14. Every year of contact play that gets replaced with a non-contact version is a year of reduced cumulative exposure during a period when the brain is still developing.
Reduce Hit Volume in Practice
Most head impacts in football, hockey, and combat sports happen during practice, not games. Cutting down on full-contact practice sessions is one of the most practical steps a team or athlete can take. Many college and professional football programs have already adopted hit-count limits during the week, reserving full-speed contact for game day.
In boxing and mixed martial arts, increased sparring exposure is directly associated with greater cognitive and balance problems. Fighters can reduce risk by limiting hard sparring sessions, using lighter contact during training rounds, and prioritizing technical drills that don’t involve absorbing blows to the head. No amount of sparring is completely safe, but less frequent, lower-intensity sessions meaningfully reduce the cumulative load.
Use Better Protective Equipment
Helmets don’t prevent CTE, but higher-performing helmets reduce the forces transmitted to the brain on each impact. Virginia Tech’s Helmet Lab rates football, hockey, and other sport helmets using a system called STAR, which tests how well a helmet reduces both linear and rotational head acceleration across a range of impact scenarios. A lower STAR score means better protection. Choosing a top-rated helmet won’t eliminate risk, but it lowers the severity of each individual hit, which compounds over hundreds of impacts per season.
Proper fit matters as much as the rating. A five-star helmet that sits loosely or tilts forward loses much of its protective value. Mouthguards, while primarily designed to protect teeth, may offer a small additional benefit by stabilizing the jaw during impacts, though the evidence for their role in brain injury prevention is less clear.
Rule Changes That Lower Risk
Some of the most meaningful progress in CTE prevention has come from changing the rules of the game itself. The NFL’s redesigned kickoff rules, made permanent in 2025, reduced concussion rates on kickoff plays by 43%. Officials can now use replay review to overturn penalties for hits to the head and neck of defenseless players, adding another layer of enforcement.
At youth and amateur levels, rules limiting full-contact drills, banning certain tackling techniques, and enforcing stricter penalties for head-targeting fouls all contribute to lowering total impact exposure across a season. If you’re a coach or league administrator, advocating for these kinds of structural changes likely does more to protect athletes than any individual piece of equipment.
Handle Concussions Properly When They Happen
When a concussion does occur, the way it’s managed affects long-term brain health. The biggest risk is returning to play too soon, particularly before the brain has finished healing, which makes it far more vulnerable to a second injury. The CDC outlines a six-step return-to-play progression that moves from normal daily activities to light aerobic exercise, then moderate activity, heavy non-contact activity, full-contact practice, and finally competition. Each step should take at least 24 hours, and any return of symptoms means dropping back to the previous step.
In combat sports, the consensus from ringside physicians is absolute: no athlete should spar or compete while experiencing any concussion symptoms. A gradual progression from light aerobic activity to sport-specific drills to sparring should only begin after symptoms have fully resolved. Rushing this timeline doesn’t just risk a worse concussion. It may accelerate the kind of protein buildup in the brain that eventually leads to CTE.
Nutrition and Brain Resilience
There is growing interest in whether omega-3 fatty acids, particularly DHA, can help protect the brain against trauma. Clinical trials have tested high-dose DHA supplementation (2,200 mg per day) in athletes recovering from concussions, based on DHA’s known role in maintaining the structural integrity of brain cell membranes. The theory is that a brain with adequate DHA levels may be better equipped to absorb and recover from impacts.
This research is still in early stages, and no supplement has been proven to prevent CTE. But maintaining adequate omega-3 intake through fatty fish, fish oil, or algae-based supplements is reasonable general brain health advice for anyone in a contact sport. It’s a low-risk addition to a prevention strategy, not a substitute for reducing hits.
Genetic Factors You Can’t Control
Some people appear to be more vulnerable to CTE than others based on their genetics. Carrying a specific variant of the APOE gene (the ε4 version, the same variant linked to Alzheimer’s disease) was associated with more severe CTE pathology in former football players older than 65. In that group, carriers had roughly 2.3 times the odds of more advanced disease staging and significantly greater accumulation of abnormal protein in frontal brain regions. Interestingly, this genetic effect wasn’t significant in younger individuals, suggesting it may influence how the disease progresses with aging rather than whether it starts in the first place.
You can find out your APOE status through genetic testing, though what to do with that information is a personal decision. It doesn’t guarantee you will or won’t develop CTE, but for someone weighing whether to continue a contact sport career, it’s one more data point. The absence of this gene variant doesn’t make repeated head impacts safe.