Your brain can’t tell if your smile is fake — and even forced laughter helps your health

Park Chang-bum, professor of cardiology / Courtesy of Kyung Hee University Hospital at Gangdong

Laughter isn’t just a spontaneous expression of joy — it may also be a powerful tool for better health, even when forced.

Humans aren’t the only species that laugh: lions laugh when courting mates, chimpanzees giggle during physical bonding and rats emit laughter-like sounds when tickled. However, human laughter is unique in that it is deeply social. Unlike other animals, people often laugh in groups, making laughter not just a personal emotion but a collective behavior that can influence well-being.

A growing body of research suggests that laughter, whether spontaneous or deliberate, may play a significant role in physical health.

In a Japanese study that followed adults over 40 for an average of 5.4 years, those who laughed less than once a month had a 95 percent higher risk of death from all causes and a 62 percent higher risk of death from cardiovascular disease than those who laughed at least once a week.

Another survey of Japanese adults aged 65 and older found that women who rarely or never laughed had a 78 percent higher risk of poor health compared to women who laughed daily. While the effect was less pronounced in men, a similar trend was observed.

In a follow-up study over three years, people who rarely laughed were found to be 42 percent more likely to develop functional disabilities — conditions that affect a person’s ability to perform normal physical, mental or sensory activities. Notably, laughing with others was found to be more beneficial than laughing alone. After six years, people who laughed frequently with others had a 23 percent lower risk of disability, and those who laughed with friends had a 30 percent lower risk compared to those who laughed alone.

Laughter is known to boost positive emotions, lower stress and help people cope with daily challenges. It also activates both social and physical resources in the body, supporting overall health. Studies have shown that laughing increases the number of immune cells, which may explain why it has long been used as a complementary therapy for pain management.

People who laugh frequently also tend to avoid unhealthy habits like smoking and excessive drinking, and are more physically active.

Laughter can also have metabolic benefits. It has been shown to help lower blood sugar levels after meals and may even support weight loss. One study found that laughing for 10 to 15 minutes a day burns around 2 to 10 kilocalories. A hearty laugh uses multiple muscle groups, increases heart rate and functions like a mild full-body workout.

Interestingly, even forced laughter can be effective. Researchers say the brain cannot distinguish between a genuine and a fake smile. Simply forming a smile-like expression can trigger the release of serotonin, the “happiness hormone,” regardless of whether one feels amused.

Whether you’re truly amused or faking it, making laughter part of your daily life can benefit your health. Finding small moments of joy, smiling at yourself in the mirror or sharing a laugh with family and friends at a set time each day may be more powerful than you think.

This article from the Hankook Ilbo, the sister publication of The Korea Times, is translated by a generative AI system and edited by The Korea Times.