The Difference Between A Real Smile And A Fake One

“Smiles form the channels of a future tear.” —Lord Byron, Childe Harold’s Pilgrimage

In A Nutshell

Admittedly, some people are better at pulling it off than others, but according to scientific research, there’s still a definite difference between a real smile and a fake one. It all has to do with the interaction of the muscles around the mouth and cheeks with the muscles in the eyes, and there’s only one unique combination of these muscle movements that results in a smile that means happiness or contentment. Other types of smiles—including the one that you give at a really bad joke—can mean anything from sadness and smugness to barely concealed annoyance.

The Whole Bushel

We smile for a lot of different reasons. We use a smile to hide our discomfort, to react to pain or grief or disgust, or sometimes to show that we’re sad. There’s only one type of smile that’s used to convey happiness, and scientists have dubbed that “Duchenne’s smile” after the French scientist Guillaume Duchenne, who did the first (though rather questionable) research into smiling.

Duchenne’s famous experiment involved the application of electric current to different areas of the face, stimulating the muscles and seeing just where facial expressions came from. Ultimately, he found that the smile that we use to convey happiness came with the use of the zygomatic major muscles in the cheeks, and the orbicularis oculi muscles around the eyes. It’s only this combination of movements that make the mouth and eyes work together to form the most recognizable smile of happiness.

Duchenne did his work in 1862, but it was all but debunked in 1924 with the even more questionably ethical experiments of Carney Landis. Landis asked volunteers to do all sorts of things from watching pornography to beheading rats, then examined their facial expressions from photographs taken during the trials. He determined that there was only one type of smile, and it was the smile that we all use regardless of what we’re feeling.

It was only in the 1970s that his theory was debunked, and researchers from the University of California at San Francisco proved Duchenne right. They mapped the exact muscles that were involved in making several thousand different expressions, and found that different muscles formed different types of smiles. In their subsequent book, they outlined 17 different smiles, some of which can be identified by a head tilt or a downward glance in addition to mouth movements.

Some of the most recent research into smiles has found that smiles of genuine happiness and other types of smiles begin in different areas of the brain. This was found by studying the smiles of people who had damage to the left side of their brain; findings indicate that true, happy smiles are controlled by the part of the brain that regulates emotion, while false, forced smiles come from the same part of the brain that is in charge of planned movements that aren’t affiliated with emotional responses.

So what’s all this mean for telling the difference between a smile that means happiness and one that’s maybe not-so-genuine?

A genuine happy smile is typically one that involves not just the eyes, but the skin around the eyes and the formation of crow’s feet. When someone’s giving you a fake smile, they often concentrate too much on what their mouth is doing, and you’ll be able to see more teeth than you would during a real smile.

While there’s obviously a practical reason to be able to tell whether or not a person’s giving you a real smile, there’s also a correlation between future happiness, health and longevity. The same researchers at the University of California looked back over 30-year-old yearbook pictures, then tracked down as many of the people in the pictures as they could. Those that were giving real smiles were statistically more likely to report they were happier in their marriages and in the overall quality of their lives; they were also more likely to be healthier and less likely to have died.

Show Me The Proof

Association for Psychological Science: The Psychological Study of Smiling
Psychology Today: What Science Has to Say About Genuine vs. Fake Smiles
Huffington Post: Can You Tell The Difference Between A Fake Smile And A Real Smile?