LONDON-Most children are taught not to lie from a young age.

But a new study from researchers at University of Toronto has found that learning to fib might actually have wide-ranging cognitive benefits.

A group of 42 preschool-aged children - none of which showed an ability to lie - were split into two factions: a control group and another group which was taught how to lie in order to win a hide-and-seek game.

The group of boys and girls, which had an average age of about 40 months, played a game where they had to hide a snack, like popcorn, from an adult over the course of four days. As part of the game, the adult had to select which hand the child had hid in the popcorn in.

If the child was able to deceive the adult, they could keep the treat.

Each child was then given a standardized test measuring executive functions, which include things like theory of mind, or the ability to understand what another person's intentions are, as well as the ability to pay attention, stay focused on tasks, organize, prioritize and plan effectively.

They found that the children who were taught to deceive ended up outperforming the control group.

'With just a few days of instruction, young children quickly learned to deceive and gained immediate cognitive benefits from doing so,' the researchers wrote. 'More generally, these findings support the idea that even seemingly negative human social behaviors may confer cognitive benefits when such behaviors call for goal pursuing, problem solving, mental state tracking and perspective tracking.'

Researchers say the study is the 'first evidence' that learning how to lie can actually improve cognitive skills in preschool-aged children.

'As parents and teachers - and society as a whole - we always worry that if a kid lies there will be terrible consequences,' said Kang Lee, a co-author of the study who has studied how kids lie for over two decades. 'But it turns out there is a big difference between kids who lie earlier and those who lie later.

'The kids who lie earlier tend to have much better cognitive abilities,' he added. 

However, it doesn't mean all parents should be teaching their kids how to lie.