Despite increasing concern about the long-term risk of dementia and other problems from heading a ball or tackling, children are still playing contact sports. Should you play it safe and stop them?

I love to watch my daughter play football, but when she heads the ball, I feel a surge of pride (she isn’t one of those who duck out the way) and a surge of fear. How many brain cells did she knock out? And what goes on inside her head when the ball hits it?

Since the case of Jeff Astle, the former West Bromwich Albion footballer who died of a degenerative brain disease in 2002, the potential risks of heading have come under intensive scrutiny. The coroner cited “industrial disease” as the cause of Astle’s death. At about the same time, Bennet Omalu, the forensic pathologist played by Will Smith in the film Concussion, was establishing a link between the sudden death of NFL player Mike Webster and a form of brain disease, chronic traumatic encephalopathy (CTE), that had previously been associated only with boxers.

But despite these findings, little has changed for children on the field of play. Sport carries risks that science is still struggling to evaluate. So how should you strike the balance between encouraging children’s competitiveness and keeping them safe?

Globally, the response of sporting bodies has varied hugely. In the US, children under 11 are not allowed to head the ball, but the Football Association in England feels there is insufficient evidence to follow suit. In England, there is no tackling in rugby for under-nines, in New Zealand it’s under-eights, in Canada under-11s. Omalu advocates no contact sports for anyone under 18.

Allyson Pollock, director of the Institute of Health and Society at Newcastle university, has called repeatedly for schools to ban tackling in rugby. Last year, she sent a list of 36 questions to the UK’s chief medical officers on this subject, and, in the absence of any answers, has sent out a follow-up. “You have to think of it as being like tobacco,” she says. “The sporting bodies fund the research.” The weight of tradition (and vast amounts of sponsorship money) is behind them. As Omalu found when he first presented his evidence to the NFL, bringing about change can be difficult.

It was watching her own son play that led Pollock to investigate injuries in youth rugby. By age 16, he had broken his nose, fractured his leg, broken his cheekbone and had experienced concussion. “When I looked at the data, 95% of [youth] players were injured by the time they left [the sport]. I thought: this isn’t worth it.” Children, she believes, should not practise collision sports. “If they are going to play rugby, I’d ask them to play non-collision rugby.”

These sorts of questions “consume a significant proportion of my working life”, says Martin Raftery, chief medical officer at World Rugby. “In life you can minimise risk, but never eliminate it.” This does not sound like a proactive response to the problem of how to reduce injuries in his sport. Why not ban tackles in school rugby? “Why don’t we stop them riding bikes?” he asks.

Facebook Twitter Pinterest Jeff Astle in 1970. Photograph: Hulton Getty

According to research published in the British Journal of Sports Medicine, tackles are responsible for 64% of all injuries in youth rugby and 87% of concussions. Raftery himself co-authored an article in the same journal accepting that “the most effective, although extreme, method for preventing concussion would be to eliminate exposure by removing the tackle from the game”. So why doesn’t World Rugby do so, at least in schools? “Well, you don’t have rugby any more.”

World Rugby is researching the possibility of changing the rules on tackling – to reduce the height at which it is permitted, for instance – but a change was first mooted in 2015 and the research is only 12 months in. Progress is slow.

Ninety years after “punch-drunk syndrome” in boxers, now recognised as CTE, was first identified, research into how brain injury relates to sport is still relatively young. There have been many cases of professional athletes who have developed brain ill-health – three of the players who won the World Cup in 1966 have dementia, for instance – but evidence of a correlation is lacking.

“There is no science that can prove a correlation between the sports impact and the pathologies that are being observed,” says Hannah Wilson of the Drake Foundation, a not-for-profit organisation dedicated to understanding concussion injuries in sport. “That’s really where the gap in our understanding is.” The foundation is funding – despite Pollock’s comments about the influence of sporting bodies – independent research into the possible increased risks of neurodegenerative diseases in retired contact-sport athletes.

Facebook Twitter Pinterest Parents can still withdraw their children if they are concerned about tackling. Photograph: SolStock/Getty Images

Willie Stewart, the Glasgow-based neurosurgeon who examined Astle’s brain and found evidence of CTE, is this month signing the contract on a research project funded by the FA to explore the connection between heading the ball and dementia.

“What we don’t know is whether people who play football get dementia more than you would expect,” Stewart says. Crucially, his researchers will examine 15,000 former professional footballers against 45,000 otherwise comparable people who were not in the sport. The volume of sampling “should be able to answer the question we’ve got: was the risk of degenerative brain disease in former footballers against population expectations?”

It will take two to three years to gather the data. In the meantime, Stewart is in favour of tackling in rugby and finds no reason to tell children not to head the ball. “But would I go out with kids and have them head the ball 20 times over? No.”

Parents, meanwhile, can check whether heading is overemphasised in training. They can withdraw their child from school rugby if they and their child object to the tackles. But the most important question to ask of any coach or teacher, Stewart says, is: “Do they have a concussion policy?” In England, the sport’s governing body, the RFU, has a concussion education programme including an online audio course for parents, and Stewart himself co-produced a pocket concussion guide for all sports in Scotland.

So, while I will continue to applaud those rare headers (until the research tells me otherwise) and committed tackles, I will do so as a concussion-literate spectator.