Footballers 50% more likely to develop dementia, study finds

Footballers are 50% more likely to develop dementia than the rest of the population, a study has found, fuelling calls to restrict rules around heading the ball in football.

Researchers from the Karolinska Institutet in Sweden, published in the Lancet Public Health journal today, compared the health records of 6,000 elite footballers and more than 56,000 non-footballers between 1924 and 2019.

They found that among male footballers playing in the Swedish top division, 9% were diagnosed with neurodegenerative disease, compared with 6% of the control sample.

The study examined differences in cognitive health for outfield players versus goalkeepers. Researchers discovered that outfield players had a 1.6 increased risk of Alzheimer's and other forms of dementia than the wider population sample. But goalkeepers – who rarely head the ball – had no increased risk of Alzheimer's or dementia, “supporting the hypothesis that mild head impacts sustained when heading the ball could explain the increased risk in outfield players,” the study concluded.

Peter Ueda, assistant professor at Karolinska Institutet and co-author of the study, said: “Importantly, our findings suggest that goalkeepers don't have the same increased risk of neurodegenerative disease as outfield players. Goalkeepers rarely head the ball, unlike outfield players, but are exposed to similar environments and lifestyles during their football careers and perhaps also after retirement.”

In contrast, the authors found no significant risk increase for football players of contracting motor neurone disease, while the risk of Parkinson's disease and overall mortality was lower among football players compared with the control group.

The findings follow 2019 Scottish research which concluded that former professional footballers were 3.5 times more likely to develop dementia and other serious neurological diseases. And a study published last year found that professional footballers are more likely to have worse brain health after age 65 than non-footballers.

David Curtis, honorary professor, UCL Genetics Institute, said: “It seems extremely plausible that repeatedly heading the ball during training and normal play produces brain damage which over time can result in dementia.

“The fact that the risk to goalkeepers, who rarely head the ball, is not increased, strengthens this hypothesis. If we assume that about one in 10 people would develop dementia anyway, then this means that about one in 20 professional footballers will develop dementia who would not otherwise have done so, as a result of heading the ball.”

In England, the Football Association is trialling banning children under 12 from heading the ball in certain grassroots competitions and leagues. If successful, it will apply to the International Football Association Board for a law change to remove heading for under-12s altogether.

But campaigners called for a complete ban on children heading the ball. Luke Griggs, chief executive of brain injury charity Headway, said:“It is important that football is willing to evolve as our understanding of the long-term implications of repeated sub-concussive impacts increases.

“We know enough now to make balanced, sensible adjustments to limit exposure to head impacts.” This includes “limiting of heading practice drills for adults, and complete bans on children heading the ball as they move through key stages in their physical and neurological development,” he added.

Dr Adam White, head of brain health at the Professional Footballers' Association, called for the Industrial Injuries Advisory Council to “to recognise dementia as an industrial disease”. He added: “We are doing all we can to improve the management of head trauma by lobbying for temporary concussion substitutions and working towards a reduction of heading in training.“

Dr Richard Oakley, associate director of research at Alzheimer's Society, said: “We now urgently need more answers to determine what lies behind this link – why dementia would start to form, how the type of injury, frequency and age at which head injuries occur may influence risk, and how we can accurately predict who is likely to go on to develop dementia after a traumatic brain injury.

“Sporting bodies need this clarity so they can put in place appropriate measures to protect players.”