Powdered Fish Bones
One pamphlet recovered from Britain read that people should use powdered fish bones for their teeth. By simply rubbing this substance on your teeth and rinsing with a vinegar and sulphuric acid mix, it ws believed that you would end up with fresher, whiter and cleaner teeth.
Famous For His (Bad) Hygiene
King James VI of Scotland became famous for his rather odd (and gross) hygiene. Not only did he wear the same clothes for months at a time, but he also kept his hat on for 24 hours a day. Yes, that means he even slept in it! He also believed that bathing was bad for the body, so he never bathed!