A wooden Pinocchio puppet
A person's nose can turn slightly red if they are lying Karina Pamplona/Flickr Creative Commons

Wouldn't life would be so much easier if fairy tales were real? We could ditch the sticky morning train and commute to work on a magic carpet, solve the housing crisis by baking homes in the oven out of gingerbread, and we'd spot a stinking liar in an instant as their nose grew away from their face like Pinocchio. But while we'll have to deal with trains and bricks and mortar for now, calling out a liar from their nose is actually possible - in theory, at least.

When we lie, a part of the brain called the 'insula' is activated, and the bottom part of our nose known as the columella, as well as the areas around our eyes, start to heat up. Studies show that this can cause the nose to subtly twitch and flare.

And it's bad news for men who might be trying to win back trust after telling porkies in the past, like Paul Hollywood who is splitting from his wife of nearly two decades four years after he cheated on her with US Bake Off co-presented Marcela Valladolid.

As the average man's columella is larger and therefore packed with more blood vessels than a woman's, it may turn red when they lie, or experience another type of emotional pressure.

"The stress of the lie can make the blood vessels dilate, making the nose itchy," body language and behaviour expert Judi James told the Daily Mail. "Nose or face-touching can also be an attempt to perform a cut-off — or a shield — with the hand to mask the facial expression."

Asking neutral questions - such as how the weather is - and noticing their response is another way to detect if someone fibbing, Dr Gregory Lantz told Psychology Today. If their body language and eye movement is out of character, then they may be stretching the truth.

Just imagine how many relationships a more dramatic Pinocchio effect would make or break. In the real world, you'll have to rely on having a beady eye or whipping out a magnifying glass in the heat of an argument. And by that point it may just be easier to simply confront your partner about any suspicions you may have. After all, fairy tales always teach that honesty is the best policy.

Read more