I have never worn a cycle helmet. They are stupid. They are only good if you make impact with a small area, such as a stone, rock, or kerb. They are insubstantial and do not offer any significant protection to full head impact by a car or impact to the ground at speed or height. Besides, not all car collisions result in brain injury and brain injury is not always the cause of death. If your torso gets crushed, a helmet will not help you.
I call cyclists that wear helmets ‘helmets’.
In Australia when they made helmets compulsory there was a drop in brain injuries. However, the compulsory requirement to wear a helmet had caused less people to cycle and this was found to correlate with the drop in brain injuries.
A recent study found that motorists were more inclined to drive closer when you wore a hemlet, unless you were female.
UK mentality on the roads is that cyclists are the enemy. I gave up cycling on the roads ages ago. Not worth the risk. British people are too impatient and hostile.