Retired Footballers Show Brain Structure Changes but No Measurable Cognitive Decline, Study Finds
Former professional footballers may experience structural changes in parts of the brain linked to memory and emotion, but researchers found no clear evidence of reduced thinking or memory performance in a new British study.
The research, led by scientists at Imperial College London, examined whether repeated head impacts experienced during a football career—including frequent heading and concussions—could increase the risk of neurological problems later in life.
The study involved 142 retired professional players between the ages of 30 and 60. Their results were compared with those of 56 healthy participants of a similar age who had no known history of contact sports, military service or previous concussion.
Researchers assessed the participants using questionnaires, cognitive examinations and magnetic resonance imaging scans.
A qualifying group of 124 former players and 40 control participants underwent structural MRI scans, allowing the research team to compare the volume of grey matter in different regions of the brain.
The findings were presented at the Alzheimer’s Association International Conference.
Former players perform normally on cognitive tests
After accounting for factors including age and educational background, the retired players performed at expected levels on tests measuring memory, attention and general thinking ability.
Researchers found no statistically significant difference between the former footballers and the healthy comparison group.
The results suggest that the structural brain differences detected in some players had not translated into measurable cognitive decline at the time of assessment.
Senior researcher Thomas Parker, a consultant neurologist at Imperial College London, said scientists are increasingly examining brain health and dementia risk through a wider range of factors.
Repeated head impacts are now being studied as a potentially modifiable risk factor, similar to the way medical professionals consider high blood pressure, elevated cholesterol and other conditions associated with later-life cognitive problems.
The researchers stressed, however, that the current findings cannot be used to determine whether an individual former player will develop dementia.
Brain scans reveal regional differences
Although the former athletes performed normally on cognitive tests, their MRI scans showed reduced grey matter volume in certain brain regions involved in memory processing and emotional regulation.
As a group, the retired players had less brain tissue in these areas than people in the control group.
The significance of these differences remains uncertain.
Only about 2 per cent of the former players displayed severe brain shrinkage that could suggest active and progressive neurodegeneration.
Researchers said this small number did not provide evidence of widespread degenerative disease among the participants.
The study also did not establish a direct link between professional football and Alzheimer’s disease.
Alzheimer’s is a progressive neurological condition that gradually damages memory and other cognitive functions and is the most common cause of dementia.
Higher levels of anxiety and depression reported
The study identified a more noticeable difference in mental health.
Around 31 per cent of the retired players met the clinical threshold for depression, compared with approximately 9 per cent of participants in the control group.
Clinical anxiety was reported by about 42 per cent of the former athletes, compared with 25 per cent of those who had not participated in contact sports.
The researchers did not conclude that repetitive heading or football careers directly caused the higher rates of anxiety and depression.
Mental health can be influenced by many factors, including physical health, retirement from elite sport, chronic pain, career disruption and personal circumstances.
However, the findings indicate that emotional wellbeing should form an important part of future research into the long-term health of professional athletes.
Long-term monitoring planned
The project is intended to become a continuing study, with participants expected to undergo follow-up assessments every two years.
Researchers hope repeated testing will reveal whether the structural brain differences remain stable, improve or become associated with later cognitive changes.
Studying former players during middle age may help scientists identify neurological developments many years before dementia would normally be expected to appear.
Much of the previous research into sports-related brain injury has relied on medical records, retrospective analysis and examinations conducted after death.
Those studies have often focused on chronic traumatic encephalopathy, commonly known as CTE.
CTE is a degenerative brain condition associated with repeated head trauma, including concussions and lower-level impacts that may occur during activities such as football heading.
At present, CTE can only be definitively diagnosed after death.
By monitoring living athletes over many years, the Imperial College team aims to better understand how repeated impacts may affect brain structure, mental health and cognitive performance over time.
Findings remain preliminary
The study has not yet been peer-reviewed, meaning its methodology and conclusions have not undergone formal independent evaluation by other scientific experts.
Researchers plan to submit a larger analysis for publication later in 2026, including additional participants and further examination of the available data.
The authors therefore urged caution when interpreting the results.
The study does not prove that football causes brain shrinkage, anxiety, depression, Alzheimer’s disease or dementia.
It also cannot predict the future neurological health of an individual player.
Instead, the findings provide an early snapshot of a group of retired athletes and establish a foundation for more extensive long-term research.
Similar pattern previously found in rugby players
The results resemble findings published by the same research team in 2025 following an investigation involving 200 retired rugby players.
That study also detected reductions in grey matter volume and higher levels of anxiety among former athletes, while cognitive performance remained within normal ranges.
The similarities between the two studies may encourage further investigation into whether repeated impacts across different contact sports produce comparable patterns.
However, more evidence will be needed before scientists can determine whether the observed brain differences are permanent, progressive or clinically significant.
Implications for football safety
Concerns about the long-term effects of heading and concussion have led football organisations to review training practices, medical protocols and protections for younger players.
Several governing bodies have introduced restrictions on heading during youth training, while professional competitions have strengthened concussion assessment and return-to-play procedures.
The new research does not provide a definitive answer about whether heading should be further limited.
It does, however, support continued monitoring of athletes and closer examination of how cumulative head impacts may affect the brain over decades.
The researchers said the field is moving toward a more complete understanding of brain health that includes physical changes, cognitive performance and mental wellbeing.
For retired footballers, the current findings offer a mixed but cautiously reassuring picture.
While MRI scans detected differences in brain structure and mental health concerns were more common, the former players did not show significant memory or thinking impairment compared with people without contact-sport histories.
The planned long-term follow-up will be critical in determining whether those findings remain stable as the participants grow older.
