[hoosieree]

I have a theory that requiring helmets would reduce bicycle usage, making people in general less healthy. It would also increase the ratio of cars to bikes, making roads more dangerous. I think the net effect would be worse outcomes.

I'd love to see evidence of this (either proving or disproving) but it seems like a hard thing to measure.

That said, I always wear a helmet when biking, but I never wear a helmet when driving, and I am aware of the irony.

[mcv]

I believe when Australia introduced mandatory helmets, bicycle use indeed dropped dramatically. That's definitely a big part of why many Dutch are opposed to mandatory helmet laws.

Helmets should probably be mandatory for e-bikes, though. They go a lot faster, and more importantly: faster than people realise.