Does forcing a smile actually lift your mood?

One thing I've noticed about my own health is that my energy improves along with my mood, not just the other way around. And I make a point of smiling and laughing every day.

But not the way you might think. I've tried putting a smile on my face for no reason, because someone said it would make me feel better. I've never been able to make it a habit. I've always needed a reason to smile.

So I wanted to know if forcing a smile actually does anything. Psychologists have fought about this for decades, and the answer turned out to be more interesting than either side expected.

The short version

• Smiling on purpose really does lift your mood, but only a little and only for a moment, about as much as looking at a few cheerful photos.
• It works even if you don't believe it will. But nobody has shown that doing it every day makes you happier, and most of the researchers doubt it.
• Smiling to hide how you feel is linked to feeling worse, not better.
• The bigger lever is laughing with other people, often. How often seems to matter more than how hard.

The famous pen study that fell apart#

In 1988, psychologists had people hold a pen in their mouth while rating how funny some cartoons were. Held in the teeth, the pen forces your face into something like a smile. Held in the lips, it makes smiling hard. The "smiling" group found the cartoons funnier.¹ It became one of psychology's best-known findings.

Then, in 2016, 17 labs repeated it with 1,894 people. The original difference was 0.82 points on a 10-point scale. The repeat found 0.03.² Basically zero.

For a while it looked like the whole idea was dead.

Believers and skeptics run the rematch#

Then something unusual happened. Researchers who believed in the effect and researchers who doubted it designed one study together, including the man who ran the original pen study. They agreed on the rules before collecting any data, so nobody could move the goalposts afterwards.

They tested 3,878 people in 19 countries. Each person made happy and neutral faces for 5 seconds at a time, using the old pen trick, copying photos of smiling actors, or simply moving the corners of their lips up towards their ears and lifting their cheeks. Then they rated how happy they felt.³

• The pen trick barely did anything (0.04 points on a 7-point scale).
• A real, deliberate smile did work. On average it raised happiness by about a third of a point on the 7-point scale, around 5% of the scale.
• That's about the same lift people got from looking at a few cheerful photos of dogs, kittens, flowers and rainbows.
• It worked with or without the photos, so a smile can nudge you up from a neutral mood, not only add to a good one.

Smiling on purpose really does lift your mood. Just not by much.

So the pen was the problem, not the idea. A review of 138 studies from about 50 years of research had already found the same thing: a real effect, and a small one. It also found no sign that only the positive studies were getting published, at least for how people feel.⁴

It works even when you don't believe it#

You might suspect that people in these studies just guess what's being tested and play along. The researchers worried about that too. They threw out everyone who showed any idea what the study was about, almost half the participants, and the effect was still there. It was bigger among people who did guess, so expectation plays some part.³

A follow-up across six experiments in 29 countries went further. Even people who were told, or personally believed, that smiling does nothing still felt a little happier after smiling.⁵ Expectation changes the size of the effect, but in these experiments it didn't account for all of it.

Why most of the researchers still doubt it as a habit#

The lift was measured seconds after a 5-second smile, mostly in young university students (average age about 27). Nobody measured how long it lasted, and nobody has tested whether smiling on purpose every day for weeks makes people happier. The studies also measured happiness, not energy or focus.

The researchers asked this themselves in the paper. They wondered whether something like asking people to "simply smile in the mirror for 5 seconds every morning" could improve well-being, and allowed that small effects might add up over time. But they wrote: "given that the similar-sized effect of positive images on happiness has not emerged as a serious well-being intervention, many (but not all) authors of this paper find it unlikely that facial feedback interventions will either."³

Nicholas Coles, the Stanford psychologist who led the study, has said the effect isn't strong enough to overcome something like depression.⁶ If you've been low for weeks, a smile isn't the fix, and talking to your doctor is.

That matches my experience. Smiling at nothing never stuck for me. What works is having a reason. Every day I share funny things with my wife, usually, or with my daughter. I subscribe to funny videos on social media and we watch them together. My wife and I talk about the things our daughter does that make us happy. When I look at pictures of my family and the things we've done together, I smile, and my mood really does improve.

When a smile becomes a mask#

There's one kind of smiling that seems to work the other way.

Researchers who study jobs like customer service call it "surface acting": putting on an expression you don't feel, or hiding the one you do, like smiling at a rude customer while you're seething. A review of 95 studies linked doing a lot of it to more exhaustion and lower well-being.⁷ A survey of 1,592 American workers who deal with the public linked it to heavier drinking, even after accounting for how stressful the job was and how bad people felt.⁸

These studies only show a link, not cause and effect (maybe people who are already struggling fake it more), and hiding your feelings for hours is very different from smiling to yourself for 10 seconds. But it's a good reason to be careful with "fake it till you make it."

I've done the mask version. When I'm very fatigued and around other people, I've smiled to hide it. Maybe it helps me feel like I can get through it, but I still feel the fatigue. I don't think smiling does anything for brain fog or fatigue.

Laughing with people is the bigger lever#

If a solo smile is a small nudge, laughing with other people looks like a bigger one, though the evidence is messier.

In a small brain-scan study, 12 men watched comedy for 30 minutes with close friends. The laughing triggered the release of the brain's own opioids, the natural feel-good chemicals behind the popular "laughter releases endorphins" line.⁹ It's a tiny study, and it was about laughing together.

In a diary study of university students, the more often people laughed, the less their stressful moments turned into stress symptoms. How hard they laughed didn't matter.¹⁰

There are also dozens of small trials of laughter therapy and laughter yoga (laughing on purpose in a group, without jokes). A 2026 review of 33 trials found less depression and anxiety, with the benefit for depression growing up to about 400 minutes of laughing in total (think 20 sessions of 20 minutes).¹¹ But these trials are small, and an earlier review found that "overall study quality was low, with substantial risk of bias in all studies."¹² The real effect is probably smaller than it looks.

The person who makes me laugh the most is my wife. Not because she tells jokes. She does and says silly things, sometimes without meaning to. She makes me laugh a lot, and she's cute.

The change I think would work best for me is making more time to laugh with friends, because that brings me genuine happiness. But that time is hard to find, and it doesn't depend only on me.

What I'd actually try#

Here's what the research supports, smallest first:

1. A 10-second smile when you notice a flat moment. Move the corners of your lips up towards your ears, lift your cheeks, and hold it. Expect a small nudge, not a new mood. This is the easiest one for me. I'd have to set a timer to do it every day, and I'm not sure how much it would do.
2. Give yourself reasons to smile. Funny videos you share with someone, old photos of people you love. In the lab, cheerful pictures did about as much as the smile, and you don't have to fake anything.
3. Laugh with other people, often. How often seemed to matter more than how hard. If you're curious about laughter yoga, the trials suggest benefits build over about 20 sessions, but treat that as promising, not proven.

And one thing not to do: don't use a smile to hide how you really feel from the people close to you. That's the version linked to feeling worse.

If you only do one thing, find something that makes you laugh with someone you love, and do it a little more often.

I still can't smile on command. But I've always needed a reason to smile, and my two best ones live with me.