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Fake Smile Or Genuine Smile? Duchenne Smiles, Explained

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If you see a smiling face, you are more likely to want to connect1 with that person than if their look is neutral or expressing a different emotion. 

Smiling invites connection and creates social harmony. But how do you know if someone is smiling or pretending to? 

In this post, we’ll explore how to differentiate a genuine smile from a fake one and give some valuable tips on spending more of your time with a genuine smile on your face.

How to Spot a Fake Smile vs. a Real Smile

Fake smiles are often asymmetrical and tend only to engage the mouth and not the eyes. Whereas Duchenne smiles (the scientific word for a genuine smile) engage the entire face and are usually symmetrical.

If you’re wondering if someone is giving you a Duchenne or a fake smile, let’s dig deeper into the signs.

Genuine smiles use the eyes.

A genuine (Duchenne) smile engages both the muscles that control the corners of the mouth and the muscles that cause the eyes to crinkle.

A forced smile only engages the mouth muscles.

Here’s your shorthand:

Genuine smile signs: 

  • The mouth is smiling (with teeth showing or not).
  • Cheeks are raised
  • Eyes are squinting
  • The skin underneath the lower eyelid wrinkles
  • Wrinkles in the corners of their eyes (crow’s feet) emerge
  • Eyebrows move down slightly

Forced smiles: Mouth is smiling, but eyes and cheeks are disengaged.

Here’s an image from researchers where the left image is a genuine smile, and the right image is fake.

An image from researchers where the left image is a genuine smile, and the right image is a fake smile.


Genuine smiles fade out.

As psychologist Paul Ekman2 points out, real smiles “fade out” naturally. Think of a video transition where one clip cuts to the next. At the same time, fake smiles will drop off suddenly.

When you experience joy, it doesn’t usually flip on and off like a switch. Something might make you feel warm and stay for a moment until the next emotion enters your body.

Genuine smiles: The smile ends gradually.

Fake smiles: The smile turns off suddenly. Or mechanically jumps down to a partial smile for a few moments, then drops off.

Here’s one example of Mark Zuckerberg turning a fake smile off abruptly:

Genuine smiles are more symmetrical.

When we create a false smile, we actively “think” to turn on certain facial muscles. However, when we’re genuinely smiling, the muscles are moving on their own, and we can’t control them.

Using this info, let’s take a look at symmetry differences:

Genuine smiles: Tend to be symmetrical. Both sides of the face are equally expressive.

Fake smiles: Tend to be asymmetrical. One side of the face could be more engaged.

Fake smiles mix with other emotions.

If you’ve ever tried to get rid of a smelly odor, you might know that you can’t just cover it up. Spraying Febreze on a mildewed carpet or slapping deodorant on a deeply musky armpit won’t do the job (usually!). 

The same is true when we try to cover up another emotion with a smile. 

For example, when you feel afraid, you tend to wrinkle the center of your forehead.

If you mask your fear with a smile, the fear microexpression will mix with the smile. You might then have a smiling mouth with a wrinkling forehead.

The result for the person you’re talking to might be similar to smelling the Febreze mildew combination. They see that you’re communicating that you are happy, but they are also picking up on other emotions, which leaves them confused and uneasy.

Genuine smiles: The entire face expresses the same emotion, and you don’t feel confused by the other person’s facial expressions.

Fake smiles: The lower half of their face looks like a smile, but the upper half looks different (wrinkly forehead, wide-open eyes, or a furrowed brow, for example).

Something feels off about fake smiles

One researcher conducted a clever study3 and found that we can detect when another person is speaking with a genuine smile over the phone! In the study, people were better at identifying Duchenne smiles than non-genuine or suppressed smiles (someone trying not to smile).

So, if you are questioning if someone’s smile is real or fake, and you’re still unsure after going through all the visual cues, then the advice might be simple: go with what you feel.

Genuine smiles: When the other person smiles, you experience joy, lightness, and ease.

Fake smiles: When the other person smiles, you experience mixed emotions, uncertainty, or discomfort.

To wrap up our practice, here’s a video comparing a genuine smile with a fake one:

Learning to read facial expressions and smile more are both useful goals. If you’d like to use science to learn to set the best goals for yourself, check out this goodie:

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The Benefits of Smiling

You’ve now got some pretty strong tools to help determine the genuineness of others’ smiles. But let’s not forget about your beautiful smile! 

There are so many reasons to smile more often. Here are a few:

Smiling is good for your health

Smiling will reduce your heart rate and help you deal with stress better when in a stressful situation. Further, giving a genuine smile with some laughter can also help reduce your blood pressure4

Smiling might help you live longer.

Researchers at Wayne State University5 looked at the size of smiles that baseball players expressed on their baseball cards. They found that the players with more intense smiles on their baseball cards tended to live longer (up to seven years).

Smiling makes people think highly of you.

Smiling is cool! Researchers6 asked participants to view an ad where the models were smiling. The models ranged from celebrities like James Dean and Michael Jordan to unknown people. Participants rated the models on a 7-point coolness scale and consistently rated people who smiled more relaxed.

Smiling makes you feel better.

Researchers looked at 138 studies7 testing more than 11,000 participants from around the world and found that when we smile, it brings more happiness to the moment.

5 Tips on How To Smile More

Indeed, you’re convinced by now—smiling is good for you! Let’s go over a few tips to help you up your smile game.

Clarify your smile triggers.

I have a friend who works as a photographer, and a few years ago, he offered to give me a free headshot. Before each picture, he’d tell me to think of my partner and what I loved about her. And my heart would slowly radiate toward my face every time until I was beaming with a warm glow.

Researchers suggest at least 50 types of smiles8 from the triumphant grin to the polite smile to the teeth-gritting smile of bitterness. 

But the Duchenne smile is linked with certain feelings—joy, giddiness, love, and warmth. So, if you want to smile genuinely more often, you can look at how to tap into those emotions.

Action Step: Write a short list of memories or images that make you smile. Does that warm your heart when you think of a particular person laughing? Or you can recall a conversation you once had that consistently evokes a giggle. Walk around with these mental images stashed away as your smile ammunition—and call forth the thought whenever you want to smile.

Find funny media

As adults, it’s all too easy to fall into the trap of “I’m a serious adult! I care about my personal growth and my career. I don’t have time to watch pointless comedies!”

I fall into this mindset all the time. But smiling, laughing, and having fun are as important as growth and achievement.

The Dalai Lama9—a paragon of wisdom—puts it: “​​”I don’t take myself too seriously! That makes me happy.” The Ancient Roman poet Horace10 puts forth a similar sentiment: “Mix a little foolishness with your serious plans. It is lovely to be silly at the right moment.”

So take it upon yourself to make time for shows, books, and movies that have no other point than to make you chuckle.

Action step: Plan a time this week to go to a comedy show or watch a funny movie.

And if you’re unsure where to start, here’s a list of 30 hilarious YouTube videos.

Seek out smiley people.

Social psychologists James Fowler and Nicholas Christakis conducted research and wrote a book called Connected. The gist of their work is simple—we become like our friends (and even our friend’s friends, and our friends’ friends’ friends!).

We take on their habits, mindsets, feelings, and health quality.

So if you want to smile more, one easy solution is to spend more time with your smiliest friends. 

While we can sponge up all kinds of tendencies from our friends, laughter is an especially contagious11 emotional expression.

Here’s a short clip of laughter spreading through a subway if you’d like some fun proof. When I watched this clip, I couldn’t help laughing!

Action Step: Write a short list of the five people you know who smile and laugh the most. Then, text one person from that list asking if they’d like to catch up this week.

Try laughter yoga

If you don’t have a large group of funny friends to call upon, don’t worry. You could consider exploring laughter yoga.

Laughter yoga is a facilitated group of people going through exercises to practice laughing. 

It may seem zany and awkward (I have tried a few laughter yoga classes, and yes, it can be both zany and awkward). Studies confirm12 that laughter yoga helps reduce stress, burnout, and cortisol while increasing satisfaction and endorphin production.

Here’s a video introducing the practice:

If you’re interested, most major cities have a laughter yoga club.

Cultivate a resting-smile-face

Most of us walk around the world with our lips in a flat line. Our default face is neutral. 

But what if your default face was a smile? It’s a radical idea in some ways, but imagine if you smiled while walking, working, or buying groceries. You’d become a joy machine!

Here are two habits to remind you to smile more often:

Habit 1: Post sticky notes around your house and office to remind you. Each time you look at one of these stickies, take it as a cue to smile, even if just for a moment.

Habit 2: Practice seeing the good in people. When you walk around, instead of seeing strangers as obstacles that you have to walk around, see if you can imagine each person as a complex human being who has been through suffering, who is trying their best to get by, and who ultimately has a good heart. And better yet, as you pass people around town, see if you can offer a moment of eye contact and a smile.

Frequently Asked Questions About Genuine Smiles

What is a genuine smile called?

A genuine smile is called a Duchenne smile. Named after the French neurologist Guillaume Duchenne, it reflects genuine happiness and is often infectious to others.

What are the characteristics of a genuine smile?

A genuine smile, or Duchenne smile, is a smile that involves the whole face; it affects not only the mouth but also the eyes. It is usually symmetrical and causes the skin underneath the eyes to bag and the eyesight to squint, creating “crow’s feet.” Moreover, genuine smiles tend to fade out naturally and gradually.

What causes a genuine smile?

A genuine smile is caused by joy, love, warmth, or other positive emotions. It is a spontaneous and involuntary response to happiness, positive experiences, or thoughts, reflecting our inner state of joy.

How do you genuinely smile?

To genuinely smile, think about memories or images that bring you joy or make you laugh. Spending time with people who make you happy or watching a funny movie can stimulate genuine smiles.

How to tell if a smile is genuine?

You can tell if a smile is genuine by looking for signs like the involvement of the eyes (they squint, creating “crow’s feet”), the fading out of the smile naturally, and whether the smile is symmetrical. Additionally, genuine smiles often evoke feelings of joy and comfort in others.

What does a smile symbolize?

A smile symbolizes happiness, joy, and social harmony. It can also signal someone being open for connection and help fulfill our basic need for belonging.

What is the key feature of a genuine smile?

The key feature of a genuine Duchenne smile is the involvement of both the mouth and the eye area. Specifically, the “crow’s feet” wrinkles at the corner of your eyes and the gradual fading of the smile are significant indicators.

Why is a smile so powerful?

A smile is so powerful because it reflects our inner state of joy, has the power to influence others, and comes with many health benefits. It can reduce stress, create social connections, and even increase lifespan, making it a powerful social and emotional tool.

Takeaways on Genuine Smiling

Sometimes, you might feel unclear if someone is smiling or not. But if you’re curious to read faces a little better, you can remember these differences between Duchenne smiles (which are genuine) and fake ones:

  • Genuine smiles activate the muscles surrounding the eyes; fake smiles do not
  • Genuine smiles gradually fade off; fake smiles cut off suddenly
  • Genuine smiles are symmetrical; fake smiles tend to be asymmetrical
  • Genuine smiles tend to be just one emotion; fake smiles might mask an emotion that can show in the upper face
  • Genuine smiles will make you feel light; fake smiles might confuse you.

And while it’s good to build the skills to assess if others are smiling, it’s also important to cultivate more genuine smiling ourselves. To do so, here are a few tips:

  • Clarify a few thoughts or memories that bring a smile to your face and return to them often
  • Take time out of your day to go to a comedy show or watch a funny movie
  • Think about which of your friends smile the most, and prioritize spending time with them
  • If you don’t have a big group of smiley friends, try going to a laughter yoga session
  • Make it a habit to smile as your default face by seeing the good in other people

I hope you’ve learned more about how to spot smiles and how to produce them yourself! If you’d like to practice your smiling form, this guide might provide a few helpful tips on how to smile.

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