Sometimes even doctors are duped, say Rachel Vreeman and Aaron Carroll. Seven myths were selected for critical review. Despite their popularity, all of these medical beliefs range from unproved to untrue.

1. People should drink at least eight glasses of water a day
2. We use only 10% of our brains
3. Hair and fingernails continue to grow after death
4. Shaving hair causes it to grow back faster, darker, or coarser
5. Reading in dim light ruins your eyesight
6. Eating turkey makes people especially drowsy
7. Mobile phones create considerable electromagnetic interference in hospitals