Patients feel less pain when they SMILE during an injection, research suggests

Help is at hand for those of us scared of needles but want to receive the coronavirus jab. The advice is simple – just smile and it will hurt less, a study found.

Researchers gave 231 participants an injection while they were either smiling, grimacing or straight-faced and asked them how painful it was.

Smilers reported 40 per cent less pain than those with a blank facial expression. 

The catch was that it had to be a ‘genuine’ smile – where someone’s eyes crinkle – and not a pretend one where only the lips move. 

Smiling may trick people’s brains into believing they are happy as it’s normally linked to pleasant situations. 

And being in a better mood – even if there is no reason for it – could make the injection less daunting so it feels less sore.

But the good news for those too anxious to smile is that a grimace uses similar facial muscles and the expression led to 39 per cent less pain, said the study published in the journal Emotion. 

 Professor Sarah Pressman, of the University of California, Irvine, said: ‘When facing distress or pleasure, humans make remarkably similar facial expressions that involve activation of the eye muscles, lifting of the cheeks and baring of the teeth.

‘We found that these movements, as opposed to a neutral expression, are beneficial in reducing discomfort and stress.’

People in the study, which is published in the journal Emotion, did not realise they were pulling a particular face to see how it affected getting an injection.

Researchers got them to smile, grimace or keep their expression neutral by putting chopsticks in their mouth to pull their lips upwards or activate muscles around their eyes.

Some people were required to smile only, while others had a ‘genuine’ smile crinkling the crow’s feet around their eyes.

It was only the genuine smile which significantly reduced the pain people reported on a scale of one to 100 from a harmless salt water jab.

Compared to people with a neutral expression, the heart rate of those genuinely smiling was approximately seven beats per minute slower.

Evidence shows happy feelings reduce stress at difficult times, and smiling is associated with happiness for many people, while transporting them back to situations where someone was not about to put a needle in their arm.

Most people automatically grimace when about to suffer discomfort or pain, which many experts believe is to get others to take pity on them and help.

But the new results suggest it may also work similarly to a smile in helping reduce pain.

It means doctors in the Middle Ages may have been on to something when they got people to bite down on wood or leather during medical procedures, forcing their mouth into a grimace.

In the study, this facial expression reduced the amount of stress people reported.

Professor Pressman said: ‘Our study demonstrates a simple, free and clinically meaningful method of making the needle injection less awful.

‘Given the numerous anxiety and pain-provoking situations found in medical practice, we hope that an understanding of how and when smiling and grimacing helps will foster effective pain reduction strategies that result in better patient experiences.’

A 2017 study by Nottingham University found that people who were happy when they went for their autumn flu jab were better protected from getting ill.

They produced up to 14 per cent more antibodies against the flu virus, with a good mood believed to boost the immune system.