When I was about five or six years old, my mom was baking something in the kitchen that used sugar. I asked for some sugar so I could eat it, and she explained that if you eat plain sugar, you'll get worms in your stomach. I believed this for many years, probably until I was at least 11 or 12.
A childhood belief about sweeties

others believed things like this
- adding too much sugar to foods would give you "sugar worms"...
Anon - My mum told me that if I ate sugar from the sugar bowl I'd get worms.— QueenB
- I use to believe that if I ate to much sugar just by itself, it would become worms inside my stomach.Anon
- I used to think that if I ate sugar out of the sugarbowl I would get worms in my stomach.— Arc
- I thought that a "sugar daddy" was a father who let his kids eat all the sugar they wanted.Anon
- I used to believe that when cordial drink said 'sugar free' that you didnt have to pay for the sugar in it!— Grace Lyon New Addington