Perhaps we should note that the rate of pedestrian deaths is far above that for cyclists. They have argued that this is because there are so many pedestrians vs. cyclists but I don't know if I would agree with that since people do not walk anywhere so their personal exposure is very low Yet the fatality rate of pedestrians is four times as high as cyclists. Cyclists, on the other hand have a very high exposure with hours in the saddle on even a moderate ride and being in the street and not protected on a sidewalk. The studies have shown that there is no reason to wear a helmet because the rates of mortality are so low and those fatal accidents were so serious that a helmet would have been of no assistance. However, this is an argument against mandatory helmet laws and not the voluntary use of helmets. If you believe that a helmet would help you that is all it takes for you to wear it.