It’s a common phrase used in an attempt to change the mood of a potentially unhappy person or to invoke optimism. Sometimes it works, sometimes it doesn’t. But is the saying true? Does it really take more muscles to frown than to smile?

Does It Really Take Less Muscles To Smile Than To Frown?

While the origins of the phrase is unknown, one thing is certain. It isn’t rooted in science. It actually takes more muscles to smile than to frown. While it’s difficult to determine exactly how many muscles are involved in smiling or frowning — not everyone smiles the same way and uses different types of smiles depending on context — the bare minimum required for a smile is 10 muscles. For a minimal frown, only six muscles are used.

According to Dr. David Song (University of Chicago Medical Center) who recently did a study on the topic, the average frown requires 11 muscles while an average smile requires 12.

However, his method of counting the number of muscles used in creating a facial expression does not take into account other variables like energy used by each muscle or the individual variability in a person’s facial muscles. While humans share the same facial muscles to express emotions, those muscles can be more developed in certain humans. This means that some people may use muscles in their face to smile or frown which other people cannot use because those muscles simply were never developed.

The Muscles Used To Smile Are:

Zygomaticus major and minor – These muscles pull up the corners of your mouth. There is one set on both sides of the face. Total muscles: 4

– These muscles pull up the corners of your mouth. There is one set on both sides of the face. Total muscles: Orbicularis oculi – Causes the eye crinkle. Total: 2

– Causes the eye crinkle. Total: Levator labii superioris – Pulls up the corner of lip and nose. Total: 2

– Pulls up the corner of lip and nose. Total: Levator anguli oris – Helps to raise the angle of mouth. Total: 2

– Helps to raise the angle of mouth. Total: Risorius – Pulls the corners of mouth to the side of the face Total: 2

Total number of muscles: 12

The Muscles Used To Frown Are:

Orbicularis oculi – Causes the eye to crinkle. Total: 2

– Causes the eye to crinkle. Total: Platysma – Pulls down lips/mouth and wrinkles the skin on portions of the lower face. Total: 2

– Pulls down lips/mouth and wrinkles the skin on portions of the lower face. Total: Corrugator supercilii and procerus – Furrows the brow. Total: 3

– Furrows the brow. Total: Orbicularis oris – Closes the mouth and puckers the lips. Total: 1

Mentalis – Causes a wrinkling of the chin. Known as the ‘pouting’ muscle. Total: 1

– Causes a wrinkling of the chin. Known as the ‘pouting’ muscle. Total: Depressor anguli oris – Pulls corner of mouth down. Bilateral. Total: 2

Total number of muscles: 11

There’s A Catch

Even though smiling uses more muscles, it is believed that it takes less effort than frowning. This is because people tend to smile more, which means the relevant muscles are in better shape. When muscles are in better shape, they require less energy (effort) when used.



In studies, it has been demonstrated that people who produced facial expressions of anger, sadness, fear or disgust produced the same physical reactions that the actual emotions would have provoked (e.g., elevated skin temperature, sweating and increased heart rate.). Similarly, in studies of people who were told to smile reported feeling happier than the control group who didn’t.

What is surprising is that even though the test subjects knew they were acting, their bodies didn’t, and so responded accordingly.

Bonus Facts:

Most primates, especially apes, have many of the same muscles that we do and use them to express similar emotional information. Chimpanzees that hunt in groups use only nonverbal cues to transmit information and to remain organized.

Humans are born with the ability to smile, it is not something that we learn. For instance, even blind babies are able to smile.

References:

Scheve, Tom. “How many muscles does it take to smile?“. Discovery Fit & Health. (2011).

Waller, Bridget M.; Cray, James J., Burrows, Anne M. (2008). “Selection for Universal Facial Emotion”. Emotion 8 (3): 435-439. doi:10.1037/1528-3542.8.3.435

Hix, John (1931). Strange As It Seems. New York: Sears Publishing Company. pp. 224.