Morrisons has challenged consumers to eat one of its jam doughnuts – without licking their lips.

The retailer is encouraging consumers to upload videos of themselves eating its jam doughnuts and sharing it via social media using the hashtag #DoughnutLickYourLips.

For every video sent in, Morrisons will donate £1 to charity Walking With The Wounded, up to a cap of £50,000. The charity provides support for injured former British armed forces servicemen and women as they transition to civilian life.

Morrisons is also giving customers the chance to try the challenge in stores across the nation.

The challenge comes as Morrisons revealed it is “virtually impossible to eat a doughnut without licking your lips”. The theory is backed by scientist Nathaniel Davis, who explains the problem is the sugar “tipping point”.

“Our lips are really sensitive, so when we eat a doughnut and the sugar gets round our mouths, the brain reacts quickly.  Sugar absorbs the natural moisture on our lips and this means our natural instinct is to immediately lick them,” said Davis.

“We also know sugar increases serotonin levels (the chemical that controls how happy we feel) and we’re naturally predisposed to want to eat sweet things. So, it’s really hard to resist licking the sugar off.”

Morrisons baking expert Martin Clayton said the retailer hoped to raise a significant amount of money by asking people to take part in the challenge.

The retailer makes more than 1.5 million jam doughnuts per week, which are priced at 50p for a pack of five.