People who play high-impact contact sports may face an elevated risk of developing dementia at younger ages, but the evidence base remains strikingly limited, according to a narrative systematic review published in BMC Sports Science, Medicine and Rehabilitation. The review, led by Thomas Faulkner and colleagues, set out to assess what current observational research actually shows about the link between collision sports and young-onset dementia, defined as dementia occurring before the age of 65.
The research team searched five databases up to November 2025, using terms covering sports associated with concussion risk. These included a wide variety of combat sports, team-based high-impact and collision sports, and individual sports with high concussion risk, alongside progressive neurodegenerative pathologies and terminology relating to concussion. Studies were eligible only if they included a measurement of a clinically diagnosable dementia in their samples and participants associated with a high-impact contact sport.
Despite the breadth of the search, only eight studies met the inclusion criteria, comprising a total of 7,385 participants. The studies largely focused on soccer and American football, with cycling and ice hockey appearing in two studies. The narrow range of sports represented is itself a notable finding, given how many athletic disciplines carry substantial concussion risk.
Methods for identifying dementia varied considerably across the included studies. Most relied on self-reporting of diagnosis, a method the authors noted in five of the eight studies. One study combined telephone assessment with self-report, and two studies drew on assessments of medical and death records. This heterogeneity in methodology meant the reviewers could not pool results statistically; instead, they adopted a narrative synthesis, grouping studies based on how closely they approximated young-onset dementia, either directly or through a mean participant age below 65.
For American football, the review found that National Football League players may be at an increased risk of developing dementia at younger ages compared to the general population. This finding aligns with growing concern that repetitive brain injury from high-impact sports participation may be a risk factor for dementia, and that brain injury has been linked to younger age of dementia onset.
The picture for association football, or soccer, was less clear-cut. Findings were suggestive of an increased risk of dementia for younger people, but the reviewers reported that a sensitivity analysis suggested this evidence is not consistent. In other words, the apparent association for soccer did not hold up uniformly across the analytical approaches the authors applied.
Overall, seven of the eight included studies showed a higher risk of young-onset dementia in athletes, and four of those reached statistical significance. However, the reviewers emphasised that existing evidence on the impact of sport-related brain injury and young-onset dementia is very limited to date, and that the broader sport and dementia literature may not reflect the experiences of people aged below 65.
The review also highlighted persistent gaps in who is represented in this research. Other demographics tend not to be considered, including female athletes, and the authors noted that current research on the association between sport participation and dementia may often omit data representative of dementia at young ages. People with young-onset dementia often have unique needs and challenges, requiring support tailored to their age and interests, which the authors argued makes it important for collision sporting worlds to understand whether young-onset dementia risk is an area of concern for their alumni.
Looking forward, the authors called for future research to place emphasis on the concern around athletes at a young age reporting dementia diagnosis, as well as considering additional sports, countries, and demographics. Until such studies are conducted, the review concludes that the question of how high-impact contact sports relate to dementia onset before age 65 remains only partially answered, with the strongest current signal coming from American football and an unresolved, inconsistent picture for soccer.
Subject of Research: A systematic review of the association between high-impact contact sports participation and young-onset dementia
Article Title: The association between participation in high-impact contact sports and development of young-onset dementia: a narrative systematic review
Article References: Faulkner, T., Swarbrick, C., Polden, M., Hill, J., Godfrey, A., & Giebel, C. (2026). The association between participation in high-impact contact sports and development of young-onset dementia: a narrative systematic review. BMC Sports Science, Medicine and Rehabilitation. https://doi.org/10.1186/s13102-026-01756-z
Image Credits: AI Generated
DOI: 10.1186/s13102-026-01756-z
Keywords: young-onset dementia, contact sports, concussion, American football, soccer, systematic review, NFL, brain injury, dementia risk, sports medicine, association, between
News Source: Cassandra Pierce. (October 28, 2026). Contact sports linked to dementia risk before age 65, review finds, but evidence remains thin. Scienmag.
