The top 30 simple things that make us smile include a kind gesture from a stranger, waking up on a sunny morning – and seeing an elderly couple holding hands.
A study of 2,000 adults found seeing a loved one get good news, receiving a surprise gift and getting a hug also feature on the list.
While others experience the same joy after getting into bed with freshly washed sheets, seeing an old friend and watching a puppy.
But for 46 per cent of people, simply having someone smile at you makes you feel happy, with 65 per cent of adults saying that it improves their mood.
And that positive boost lasts for an average of more than 13 minutes, leaving them more likely to be kinder to others (37 per cent), be more motivated (19 per cent) or make a bold decision (nine per cent).
Bupa Dental Care commissioned the research as part of National Smile Month, to highlight the benefits the friendly gesture can have.
However, an experiment saw just 21 per cent of adults return the friendly gesture from a stranger.
During a two-hour period, actress Zara Naeem smiled at 112 different people as they walked past her - with only 24 replying with the same expression.
Psychologist Jo Hemmings said: “When we smile, a number of psychological and physiological changes occur that impact both ourselves and those around us.
“Smiling releases endorphins, dopamine and serotonin – hormones which improve our mood and our sense of well-being – and also reduces cortisol, our stress hormone, making us feel less anxious and more relaxed.
“A genuine and spontaneous smile which reaches our eyes – known as the Duchenne smile – can also lower our blood pressure and boost our immune system, by increasing our production of white blood cells.
“Smiles also have a positive effect on those around us, by reinforcing friendship, kindness and social bonding as well as having a contagious effect, creating positivity in those on the receiving end of a smile.”
Reasons why people don't always return a smile
The research also found the average adult claims to smile at a stranger five times a week – but 16 per cent admit they rarely or never return the gesture.
Of these, a third blame it on simply being lost in their own thoughts and not paying attention to what is happening around them, while 20 per cent put it down to being in a rush.
But 27 per cent avoid smiling at others over fears they will ‘look weird’ and 14 per cent are too embarrassed.
However, when a stranger smiles at them, half of adults feel happy and 32 per cent feel uplifted.
Others feel comforted (11 per cent), ‘warm and fuzzy’ (15 per cent) and confident (11 per cent).
Less than one in 10 felt a negative emotion, such as confused (eight per cent) or sceptical (nine per cent).
Despite this, less than half (48 per cent) always return a smile from a stranger, with 34 per cent of those worried the grin was not meant for them.
While 32 per cent claim to be so surprised by the gesture that they don’t react quick enough.But when the smile is not returned, 30 per cent are still pleased they made the effort – as you never know what someone has going on in their life.
Caitlin Miller, head of dental hygiene and therapy at Bupa Dental Care, which is marking its 25th anniversary throughout 2024, added: “The power of a smile is huge – especially when it comes from someone else and is unexpected.
“We’ve all been there, when we’ve missed to smile back at someone, but equally when we’ve caught a smile from a stranger, and it sets us up positively for the day.
“The impact it can have on you and someone else can’t be underestimated.”
Caitlin's tips to improve your smile
Smile tips from Jo Hemmings
1. Make momentary eye contact with the person you want to smile at, and smile in a relaxed manner – nothing too over the top.
2. Feel happy that you are about to smile at someone – this will then be projected in your smile and make it feel more natural.
3. Be prepared for the other person to not return the smile. However, know that you’ll feel good about smiling at them.
Top 30 things that make you smile
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