World Smile Day: The surprising health benefits of smiling
Today is World Smile Day, which encourages people to spread joy through a simple act of kindness.
Although our smiles are (usually) spontaneous, it turns out that they're hugely powerful.
According to research, a natural smile can boost your health by helping to relieve stress and pain – and can even make you seem more attractive and live longer.
Smiling can make you happier
Science shows that smiling causes a chemical reaction in the brain, releasing 'happy' hormones such as serotonin and dopamine. Habitually smiling can therefore help put you in a positive mental space, according to experts, increasing your productivity and creativity.
Even a forced smile can improve your mood. One study, conducted in 2012, found that people who smiled when recovering from stressful tasks had lower heart rates than those who had neutral expressions.
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"This is not going to cure you if you have chronic stress or a major life event like a tornado," said Dr. Sarah Pressman, co-author of the University of Kansas study. "But it's almost impossible to be really angry or really stressed with this big smile on your face... You can't help but reduce that negative effect."
Smiling doesn't just impact your mood – it's considered contagious because it prompts other people to 'mirror' your expression and smile back. In fact, people who smile often are apparently seen as more likeable and attractive.
Experts have identified one particular smile – known as the 'affiliation smile' – that can help repair trust after someone has been untrustworthy.
Smiling can boost your physical health
Smiling has also been linked to improved physical health, including lower blood pressure, a better immune system and longer life.
Researchers who studied photos of 230 baseball players from the 1950s found that those with the most genuine smiles tended to live the longest. They added that people who smile genuinely in photographs "may be basically happier than those with less intense smiles".
Smiling when running can relieve muscle tension and make you faster, according to a separate study, while smiling or grimacing while getting an injection can significantly reduce the pain from the needle.
