Can you believe it? It’s more safe to ride a bicycle without a helmet! So says a man named Bill. And a judge. But what does the science say? We’ll get to that in a second. But first, a rant.

The recent debate in Australia about the benefits of wearing a helmet while bike riding is very similar to the Climate Change “debate”. After decades of research, hundreds of scientists come to a very clear consensus: wearing a helmet can reduce your likelihood of getting a brain injury if you’re involved in an accident while riding a bike.

Helmets prevent injury through several avenues. Firstly, they share the load by distributing the impact of a forceful hit over a larger area than the head alone. Secondly, helmets absorb the impact, and finally, they provide a barrier for objects – like unlikely nails sticking up from the road. All clear right? Human induced Climate Change is real.

But then, one or two people come along and poo poo it for the rest of us. These people could be scientists, or not. And if they are scientists they’re not necessarily experts in the field they are tackling. So, these individuals take the decades of research, cherry pick the studies they like, forget inconvenient words like “not significant” results, fumble about with the statistics and viola! Climate change doesn’t exist. And you’re better off riding naked than wearing a helmet.

Enter Bill Curnow and the Cyclist Rights Action Group. Bill is not a neurologist, or an accident prevention expert. But neither am I, so let’s leave that alone. According to Bill, the benefits of helmets “remain under question.” In a book chapter he wrote entitled, “Bicycle Helmets: A Scientific Evaluation” Bill says that helmets may increase the angle that your heat rotates if you’re in an accident, because the helmet can grip the road. He says, this rotational, or “angular acceleration” is to blame for most brain injuries on bikes – and research has shown it, therefore helmets can be harmful.

Problem 1: it’s not just angular acceleration that causes head injuries from bike accidents, that’s only half the story. M. Franklyn from the Monash University Accident Research Centre, Monash University, Australia says that head injuries are also caused by banging your head on the road from an accident. And, helmets are very helpful in reducing injuries from these accidents.

Problem 2: there’s not good evidence demonstrating that helmets “increase” the angular acceleration in real-life accidents. Rather, the evidence suggests helmets don’t help to reduce angular acceleration.

And even if Bill is right, and helmets somehow grip the road and increase angular acceleration, this would only be relevant to a particular kind of accident. For example when you are contacting the road head first and your body is in a particular position. When trying to establish if helmets can really prevent injury it’s much more accurate to get incident reports from real bike accidents and see if wearing helmets reduced the likelihood of injury. And this has been done. Many times.

Take M. McFadden of the Australian Transport Safety Bureau who collated sixteen studies on helmets and injury published between 1980 and 1995 which encompassed over 10,000 bicycle injuries (Accident Analysis and Prevention 33(2001) 345-352). The results? Helmets reduce the risk of head injury by at least 45%, they reduce the risk of brain injury by 33%, facial injury by 27% and fatal injury by 29%. “The associations are compelling,” writes McFadden in the paper.

While some of those 16 studies did find that riders who wore helmets had larger injuries than non-helmeted riders, overall the results are clear. And we can’t cherry pick our research, just because we want to wear a top hat and ride a bike to the races.

Other helmet nay sayers claim that people who wear helmets are more likely to risk-take when riding, and so are more likely to endanger themselves (but the research above doesn’t show that – because helmet-wearers have less injuries).

And then there’s the argument that wearing a helmet is such an inconvenience that it detracts riders, therefore doing more harm than good by having less environmentally friendly commuters on the roads. There is preliminary evidence that less people ride when there are compulsory helmet laws, such as in Australia. But it’s not such a big deal to grab a helmet, and certain activities in society have proven resilient to similar inconvenient laws. There are many cars on the road despite compulsory seat belt laws, and people still go to pubs to drink, even though they’ll have to smoke outside.

Finally there is claim that we shouldn’t live in a grandmother state. “Hey, if I want to increase my risk of injury let me do it.” It’s funny, because rarely do these people say, “I love paying for my private health insurance.” If you want the state to fund your health care – then you’ve got to allow them to put in place sound measures to prevent injuries.

To make a long story short: Yes, you should wear a helmet when bike riding. Yes, Climate Change exists. And no, don’t trust every person using scientific sounding words. Except for me.