human
What's an argument for and against wearing a helmet when riding a bike?
assistant
Argument for Wearing a Helmet When Riding a Bike: 
1. Helmets are designed to protect your head from injury in the event of a crash, so it makes sense to wear one while biking.
2. Helmets can also help reduce the risk of concussion, which is especially important if you plan on doing any strenuous activities like mountain biking or downhill racing.
3. A helmet will also help keep your hair out of your face while riding.
4. It’s not just about protecting yourself; helmets can also be used as a form of identification should you ever need to call for help.
5. Finally, helmets make you look cool!