A scientist leading a landmark study into the potential health risks of playing professional football has said balls should be sold with a warning.
Professor Willie Stewart, who leads a team at the University of Glasgow currently researching the link between football and dementia said that, while the sport has many physical and mental health benefits, it can also be dangerous.
'We're at the point with this current data to suggest that footballs should be sold with a health warning saying that the repeated heading of a football may lead to increased risk of dementia,' Professor Willie Stewart said.
'I think we will have to ask the difficult questions: is heading a football absolutely necessary to the game of football? Or can some other form of the game be considered?,' The Times reported Stewart as saying.
'Maybe professionals - with full support from neurologists, medics and all the medical backup and knowledge of risk they are taking - continue to play full-contact heading football but maybe at the community level and youth level we start talking about a game without heading.'Insurance Loans Mortgage Attorney Credit Lawyer
Research conducted by Prof Stewart's team found that professional footballers who play in defence are five times more likely to develop dementia than people in the general population, new research has found.
Defenders suffer repeated blows to their head, mainly through heading leather footballs and colliding with other players.
However, goalkeepers are no more likely to develop the neurodegenerative condition than members of the general population, according to the study.
Researchers said the risk varies by position and career length, but not by the era in which they played.
The new findings also show that neurodegenerative disease diagnoses increased based on the length of a career, with a five-fold increase in those with the longest careers - defined as more than 15 years.
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Professional footballers who play in defence are five times more likely to develop dementia than midfielders, strikers and goalkeepers, new research has found. Pictured: Conor Coady (left) and Ryan Fraser (right), jumping for a header
Neuropathologist Prof Willie Stewart, has previously established that former professional footballers are three-and-a-half times more likely to die of neurodegenerative diseases than the general public.
Now he and his team have found that defenders are five times more likely to develop dementia, while the longer a player's career the bigger their risk of neurodegenerative disease is.Insurance Loans Mortgage Attorney Credit Lawyer
However, the era in which a footballer played — whether that be the 1930s, 60s, 70s or late 90s — had no bearing on the risk.
Goalkeepers had a similar risk of dementia as the general population, but for outfield players the risk was almost four times higher.
Experts at the University of Glasgow have been investigating fears that heading the ball could be linked to brain injuries.
The long-awaited study, commissioned by the Football Association (FA) and Professional Footballers' Association (PFA), began in January 2018 after claims that former West Brom striker Jeff Astle died because of repeated head trauma.
It has compared the deaths of 7,676 ex-players — all of whom were born between 1900 and 1976 and played professional football in Scotland — to 23,000 from the general population.
Prof Stewart, a consultant neuropathologist, also wanted to know whether the risk of neurodegenerative disease varied by player position, length of career or playing era.
The results showed that goalkeepers had a similar risk to the general population of developing dementia.
However, the risk for outfield players was almost four times higher and varied by player position, with risk highest among defenders — around five-fold higher.
The new findings also show that neurodegenerative disease diagnoses increased based on the length of a career, ranging from a doubling of risk in those with the shortest (defined as less than five years) to around a five-fold increase in those with the longest careers (more than 15 years).
However, despite changes in football technology and head injury management over the decades, there is no evidence of a difference in risk between those who played in the 1930s, 60s and 70s — with rain-sodden, heavy-leather footballs — and the late 90s.
Although balls are lighter today, they now travel more quickly – up to 80mph in the professional game – and as a result can cause even more damage.
Prof Stewart said: 'We have already established that former professional footballers are at a much greater risk of death from dementia and other neurodegenerative disorders than expected.
'These latest data take that observation further and suggest this risk reflects cumulative exposure to factors associated with outfield positions.'
The long-awaited study began in January 2018 after claims that former West Brom striker Jeff