Two former Premier League players – Gary Pallister and Steve Howey – have said so BBC Sport on their health fears after years of heading footballs.
Howey, who is one of the plaintiffs in the lawsuit, said he underwent exams that showed cognitive decline.
Leading campaigner Judith Gates, of Head Safe Football, has written to Culture Secretary Lisa Nandy to call for heading the ball to be declared a national health issue to protect players in the future.
Gates’ husband Bill, a former Middlesbrough defender, died last year aged 79 from chronic traumatic encephalopathy (CTE). She founded the charity Head Safe Football to raise awareness of the danger of head impacts and signs of head trauma.
The new study was funded by the Football Association, the Professional Footballers’ Association, the Medical Research Council and the US National Institutes of Health.
Published in the medical journal Jama Network Open, the study examined electronic health records of 11,984 former professional footballers and 35,952 matched individuals from the general population in Scotland.
The researchers compared major risk factors for dementia in the two groups, including history of smoking, depression, alcohol use disorders, diabetes, hypertension, hearing loss and obesity.
Overall, the study team found that rates of these risk factors were similar – or lower – among former players.
Former professionals were at lower risk of disorders related to alcohol, smoking, diabetes and obesity. Research found they were at similar risk of hearing loss, depression and hypertension compared to the general population.
Stewart told BBC Sport the report “really moves the conversation forward a bit”.
He said: “What we find is that these footballers are generally healthy men with a good lifestyle.
“Their blood pressure is good, their weight is good, they don’t smoke, they don’t drink, but they have a real problem with dementia, which is still there, and which we believe is linked to the injuries to the head. head, head impacts in sport This is the problem we face here.
The FA said: “We continue to invest in and support multiple projects to better understand this area through objective, robust and in-depth research.
“We have already taken many proactive steps to examine and address potential risk factors that may be associated with playing football, while ongoing research continues.”
The Professional Footballers’ Association, the union for professional footballers in England and Wales, has a dedicated brain health team to support former members concerned about brain health and educate current players about brain health in football.
In September 2023 he launched the Football Brain Health Fund, making an initial £1 million available to help former players and their families who have been affected by dementia and other neurodegenerative conditions.