My mother used to tell me not to drink soda in the morning or I would get a stomach ache. I held this belief until I was in college and even told my girlfriend not to have her morning diet coke because of this.
A childhood belief about drinks

others believed things like this
- I used to think that if you mixed a diet drink with a regular drink, it would explode. Anon
- I used to belief that the birth mark on my dad's leg was where he spilled his coffee... EVERY morning.— Liz
- I thought a stomach ache was a stomach egg— Catherine
- I thought that soda was also called "pop" because if you drink too much of it, you'd explodeAnon
- I thought there was a legal drinking age for soda (I had always been told that soda was not for children).— Dial Zero
- I use to think that alka seltzer tablets were instant 7UP soda until one day I tested my belief. — aj