Your arm will get chopped off if you stick it out of a car window. If you swallow the pips of an apple, a tree will grow in your tummy.
Chewing gum takes 25 years to digest, and if the wind changes when you're pulling a silly face, you'll get stuck like that forever.
Few of us forget the half-truths we were told as kids – I vividly remember my dad telling me clever little lies designed to make sure I didn't meddle with stuff I shouldn't.
But now it seems those fibs pave the way for how we parent too, because research just published by Warburtons reveals that almost half of mums and dads think creative tales (aka lies) are a necessary part of parenting.
The lies parents admitted to telling in the survey were really quite harmless – stuff like 'the ice-cream van only plays music when it's run out of ice-cream' and 'there's a baby dragon in the hand-drier who needs to practise his fire-breathing on your hands' – but they make a real impact in childhood.
Her are some of the best porky pies that my friends and I were fed when we were children . . .
1 My parents found me in a peacock's nest by the river. My brother told me this. And I believed him. Until he told me that my dad actually found me in his beer.
2 Pressing the 'record' button on our video player would make the telly explode. And the cigarette lighter in his car was the eject button, which would fire me 50 feet into the air if I ever touched it.
3 My friend Claire was told that the man in the moon or the 'bogey man' would come and take her away if she didn't go to sleep. She was understandably terrified.
4 Another friend was warned off boiled sweets by her grandmother, who told her that eating them would burn a hole in her tongue.
"I still don't eat them, ever," she says, shuddering.
5 "Always use scissors to cut the thread when you are sewing. If you snap it with your teeth, tiny bits of cotton go into your body and wrap themselves round your heart and you die." (That's another gem from the grandmother with a morbid fear of boiled sweets.)
6 My friend Renée says her dad had a single expert 'answer' that suited all the questions she posed as a child.
"We'd be at the beach and I'd ask: 'Dad, what makes the waves do that?'" she recalls.
"Dad's favourite answer was simple: 'It's all done with mirrors.'" Renee says she still doesn't know how waves work.
7 Liz, a mother of two, believes wholeheartedly in the cautionary tale that she was told in childhood: If you unscrew your belly button, your bottom will fall off.
8 My friend Julie had a penchant for popping empty crisp packets as a child. Presumably to put a stop to that, her grandmother told her that every time anyone popped a crisp packet someone, somewhere, lost their job.
Julie later discovered that her father grew up believing the same creative tale, and for years they both harboured secret guilt when unemployment levels rose.
9 The parents of a friend-of-a-friend told her that only people on very long journeys were allowed into Little Chef restaurants.
"This was to stop me begging to go to the Little Chef on the outskirts of our hometown," she explains. "I asked: 'But how would they know you weren't on a long journey?'
"Mum told me they looked at your car registration and if you had a local one you weren't allowed in – think of all the hungry people who had driven a long way and really needed something to eat.
"I believed this until, at the age of 21, I was being driven to meet my new boyfriend's parents by his sister-in-law.
"She suggested we stop at a Little Chef on the way for a coffee. 'But are we on a long enough journey?' I piped up. 'They check the car registrations and if you have a local one, you aren't allowed.'
"As soon as I said the words aloud – to a car full of graduates – I realised it couldn't be true. Never have I felt such a complete idiot."
10 Here's one that could come in handy when your own kids ask about the birds and the bees. My friend Dorian's parents stored garden seeds in the loft where it was dry so they wouldn't germinate.
"Somehow they left me with the impression that this was where children came from," Dorian recalls.
"When you wanted a new baby, you picked one from the basket of seeds in the loft. I believed this until long after I should know better."