
"It takes more muscles to frown than smile"
If, like me, you've been hearing this for years you will have heard many different statistics. The latest being that of the 53 facial muscles we all have, it takes 17 to smile
and 43 to frown.
The educated would argue that there could never be such a wide gap between the two figures. I tend to agree!
So I decided to do some research.
For the enquiring minds out there you might be interested in the following detailed accounting of the relevant muscles used put together with the aid of David H. Song, MD, FACS, plastic surgeon at the University of Chicago Hospitals. This surgeon reconstructs faces so he ought to know. 
My apologies if this list seems obsessive and technical but but we're going to settle this once and for all.
Deciding which of the 53 facial muscles are important in smiling or frowning is a bit arbitrary as many make only minor contributions, and depending on the intensity of the expression may not be involved at all. I've listed here only the ones that the surgeon feels are important.
Muscles involved in a "zygomatic" (i.e., genuine) smile:
Zygomaticus major and minor. These muscles pull up the corners of the mouth. They're bilateral (one set on either side of the face). Total: 4.
Orbicularis oculi. One of these muscles encircles each eye and causes crinkling. Total: 2.
Levator labii superioris. Pulls up corner of lip and nose. Bilateral. Total: 2.
Levator anguli oris. Also helps elevate angle of mouth. Bilateral. Total: 2.
Risorius. Pulls corner of mouth to the side. Bilateral. Total: 2.
Grand total for smiling: 12.
Principal muscles involved in a frown:
Orbicularis oculi (again). Total: 2.
Platysma. Pulls down lips and wrinkles skin of lower face. Bilateral (though joined at midline). Total: 2.
Corrugator supercilii (bilateral) and procerus (unilateral). Furrow brow. Total: 3.
Orbicularis oris. Encircles mouth; purses lips. Unilateral. Total: 1.
Mentalis. Depresses lower lip. Unilateral. Total: 1.
Depressor anguli oris. Pulls corner of mouth down. Bilateral. Total: 2.
Grand total for frowning: 11.
Despite the fact that smiling uses more muscles, it takes less effort than frowning. People tend to smile more frequently, so the relevant muscles are in better shape. You may feel this conclusion assumes a rosier view of the human condition than the facts warrant, but I defer to the doctor.
Incidentally, a superficial, breauty-queen smile requires little more than the two risorius muscles. So if your goal in expressing emotion is really to minimize effort, go for insincere.
So what does that prove? - I really don't know but go on - use that extra muscle and smile!
GO ON SMILE....EVERYONE WILL WONDER WHAT YOU'VE BEEN UP TO