This headline made me read the article.  How in the world could wearing a helmet be ‘more dangerous’?

The answer was a little surprising:    

Cyclists who wear protective helmets are more likely to be knocked down by passing vehicles, new research from Bath University suggests. 

The study found drivers tend to pass closer when overtaking cyclists wearing helmets than those who are bare-headed.

Aah, so it’s a risk from drivers that increases.

Dr Walker, a traffic psychologist from the University’s Department of Psychology, said: “This study shows that when drivers overtake a cyclist, the margin for error they leave is affected by the cyclist’s appearance.

“By leaving the cyclist less room, drivers reduce the safety margin that cyclists need to deal with obstacles in the road, such as drain covers and potholes, as well as the margin for error in their own judgements.

Read the article to see how they gathered their data, it’s interesting.

And, as both a driver and a cyclist I think the underlying premise is correct: less space is given to bike riders wearing helmets.  As a driver I think of a helmet cyclist as a predictable actor, there to ride, usually quickly and in as straight a line as possible.  I (now) realize I give a wider berth to the more casual rider.

And I can attest cars don’t mind getting close to me while riding, though I never ride without a helmet, so can’t say about whether I get more or less space with / without.

Unusually for me, I’ll let the BBC have the last word:

However, a spokesman for the Royal Society for the Prevention of Accidents insisted: “We wouldn’t recommend that people stop wearing helmets because of this research. Helmets have been shown to reduce the likelihood of head and brain injuries in a crash.

“[The research] highlights a gain in vulnerability of cyclists on our roads and drivers of all types need to take more care when around them.”