The case for bike helmets isn’t cut and dry. Personally I don’t like the smugness that often goes with purchasing safety kit. Ticking a box which says safety is very different from increasing safety. There are surprisingly good, well-researched arguments being made against bike helmets. Let’s separate three different helmet debates:

Obviously there is the protective value of helmets to cyclists as seen from the A&E wards. This is a much more difficult case to argue than you’d think. Car drivers drive more recklessly around visibly protected cyclists than around vulnerable-looking cyclists. Some cyclists get cockier when they wear a helmet than when they’re not. The statistics are skewered anyway because cyclists who never wear helmets are considered to be generally more gung-ho than their careful, helmet-wearing counterparts. As Ben Goldacre, author of “Bad Science” concludes in the British Medical Journal: “At an individual level, what is the effect of wearing a helmet? Many variables are unmeasured and possibly unmeasurable.”

Even if you assume that helmets reduce injuries in society, it’s a harder job still to decide if making helmets compulsory are good for public health. There is minimal reduction in head injuries if you introduce a law about helmets for cycling, like various Canadian provinces have done. There is however a massive fall in the number of laid-back, occasional cyclists. “Helmet laws do not appear to be beneficial because they disproportionately discourage the safest cyclists”, one study concluded. Not a smart public policy then when heart and lung disease are the real killers in society, not head trauma.

Thirdly, where does this leave you and your little nipper on her first bike? Tour de France winner Bradley Wiggins advocates helmet use. He's a guy who can hit 50 miles an hour in a very crowded peloton. Let’s compare that with the commuters and bakery-visiting cyclists of the Netherlands and Denmark, where helmet use is rare and head injuries statistically very low, according to Goldacre. Your child, whether on a pedal bike or a balance bike, really shouldn’t find himself in a situation where head injuries are remotely likely. Children do not have the ability to assess the speed of cars or to anticipate the behaviour of drivers until their teens. Child cyclists are best off in parks, on cycle paths or – in upper primary school – behind an adult cyclist on a country road. If parents enjoy being fearful – and some really do – they could worry about your regular “pebble in the way/hole in the tarmac” accident and they could purchase rollerblade-style knee and wrist protectors.

“What if a drunk driver veers off the road, onto the pavement exactly where my child is cycling and mows him down”? If that is your scenario planning, then you should be applauded for buying your child a bike at all.

Scientists say they “dread” questions about bike helmets:  http://www.bmj.com/content/346/bmj.f3817?ijkey=I5vHBog6FhaaLzX&keytype=ref