This topic has come up several times now on HN and the conversation is always very frustrating. The debate tends to run towards "no one will tell me to wear a helmet". The same studies are cited as supporting one side or the other when all the studies are clearly insufficient.

It's good that HN doesn't take things are face value, and the discussions here seek to understand unintended consequences. But sometimes a cigar is just a cigar and anecdata does in fact equal data.

Unfortunately cycling is dangerous because - in most countries - cyclists share the road with cars and trucks. There's only one winner in a cyclist vs car showdown. If you cycle somewhere that doesn't have nice cycling infrastructure a helmet is a great idea. A helmet will not automatically turn you into a target for indifference or road rage from motorists - that's the default posture of most motorists towards cyclists, helmet or not.