> Additionally, I've never seen any research showing any kind of demographic relationship to severity of head injuries in bicycle accidents. The effects of a h

> Additionally, I've never seen any research showing any kind of demographic relationship to severity of head injuries in bicycle accidents. The effects of a helmet on overall safety when ridden at low speed on dedicated bike paths is very different from when ridden at high speeds in traffic with no bike lane. Thus the the design of the city and streets (geography is perhaps not the perfect term for this) and the what/how of the local culture's bike riding behavior (perhaps demographics is a bad term for this, not sure of a better one.) have huge impacts on how much a helmet affects your safety simply because the risk profiles are very different. The data is messy due to regional variability plus the difficulty of reliably removing the confounds mentioned above. I would never discourage someone from wearing and will actively encourage it when riding in bicycle hostile areas. At the same time, I think the push for helmet laws and helmet education is often a cop out to avoid talking about how we need to redesign cities to support safe bicycling. If we did the later, we would see much larger safety gains and the former would be much less necessary.