Retired British professional soccer players exhibited structural brain differences and elevated rates of anxiety and depression but no signs of cognitive decline in a new study examining whether repetitive impacts like heading the ball increase dementia risk.
Study Design and Participants
The research, led by Imperial College London, included 142 former players aged 30 to 60 and compared them with 56 similarly aged healthy individuals with no history of contact sports, military service, or past concussions. Researchers used questionnaires and cognitive tests, and analyzed structural MRI brain scans from a qualifying subset of 124 players and 40 control participants to check for regional differences in grey matter volume.
Key Findings: Brain Structure vs. Cognitive Performance
After adjusting for factors like age and education, the former players scored as well as expected on memory and thinking tests, showing no significant differences compared to the healthy control group. However, brain scans revealed that, as a group, the players had less brain tissue in areas controlling memory and emotion than the control group. Only 2% of the former athletes showed individual signs of severe brain shrinkage that would indicate active, progressive neurodegeneration.
Mental Health Concerns
Athletes reported much higher rates of mental health struggles: 31% met the threshold for clinical depression compared to 9% of the control group, and 42% reported clinical anxiety versus 25% in the control group.
Context and Significance
The authors presented the study at the Alzheimer's Association International Conference on Sunday. They described their work as part of a major scientific push to treat repetitive head impacts as a potential modifiable risk factor for dementia in late life, similar to how doctors manage high blood pressure or cholesterol. This study lays the groundwork for a long-term investigation, with researchers planning to monitor the players every two years.
“The field is taking a more holistic view of brain health and dementia risk,” said senior author Thomas Parker, a consultant neurologist at Imperial College London.
Limitations and Future Research
The study has not been peer-reviewed. Researchers expect to submit a paper with a larger sample size and additional analyses later this year. The study did not prove a direct link to Alzheimer's disease, a progressive brain disorder that gradually destroys memory and is the most common cause of dementia.
Most research into sports-related brain damage has relied on post-mortem reports and retrospective medical records to study chronic traumatic encephalopathy (CTE), a degenerative disease linked to repeated head trauma that can currently only be diagnosed after death. The Imperial College research follows athletes in mid-life, helping track neurological changes years before dementia would typically develop.
The results mirror the team's previous peer-reviewed findings from 2025 in 200 retired rugby players, which showed similar grey matter reductions and elevated anxiety but normal cognitive performance.
Researchers cautioned that their findings cannot predict individual dementia risk. “We're at a very early stage of translating these findings to individual risk prediction,” Parker said.
