I would be able to help if you had a picture of it up
Answer:
something that harms you or others like smoking for example
Explanation:
Older generations had more accurate health information, and people were more active.
Ask this in the physics area next time please, but turn to someone you trust or if your young an adult, like your parents or your teachers. Maybe even your friends. No matter what age tell someone and if they don't know then get medical help if they can't.