My girlfriend and I both cycle a lot, but she infuriates me by refusing to wear a helmet. Her only reason is pure vanity - it would ruin her look. Contemporary helmets look too "spacey" or "sporty", she says, asking why no one designs helmets for fashion-conscious young women. I have been unable to track one down. Can you help me protect my girlfriend's valuable, if stubborn, brain?

Tom Simonite, via email

Tricky. The main choice in helmet aesthetics is between the sporty look and the grunge-o-matic snowboarder style. Either way, a coiffure catastrophe, I fear.

All you can do, Tom, is relax about your girlfriend not wearing a helmet. It has to be a matter of personal conscience. Rationally, yes, cyclists should wear helmets; but rationally, so should motorists - 14 times as many car passengers as cyclists per year die of head injuries. In the scheme of things, life years gained by the health benefits of cycling outweigh years lost by accident fatalities by 20:1.

Obviously, though, there ought to be haute-couture millinery in expanded polystyrene. Hatmaker to the stars, Philip Treacy, where are you when we need you?