There used to be a type of medicine that was advertised on the TV, I think it was an antacid but I can't remember what it was called, for which the add slogan was "Suck them and see."
The way the voice over guy said it made it sound like "Sucamin C" which I presumed was something like Vitamin C, but perhaps a man made version, or something equally as dense.
A childhood belief about adverts

others believed things like this
- I use to believe the sound that a car made when it was running low on gas was what they called horse power...— Bianca
- I had my wife convinced that Steven Hawking made his fortune as the original voice for the speak N spell toy.Anon
- I used to believe that the bubble gum medicine was really made of bubble gum. i believed this until i was 16.— Shawn
- I had tinnitus as a child and used to believe that it was the sound that the devil made when he was closeby— Helen
- I used to think that the sound made from airplanes flying over me was the antenna scrapping across the sky.— Richard J Brown
- I used to think that if someone gave you acid, you could completely counter the effects by taking an antacid.— abracadaver