Last week, I fell off my bike and hurt myself real bad. I bruised my elbow and sprained my wrist. My injuries would have been worse if I hadn't been wearing my bicycle helmet. My doctor asked me to tell this to all my friends so that they would wear helmets too. I told my teacher and she asked me to make a public announcement during the school assembly. I had to talk about the accident and how the helmet protected me.

The most important message in the above passage tells us that ____________________.