Dimples are one of those little quirks of human anatomy that look mysterious but have a surprisingly simple explanation.
So, what actually causes them?
Cheek dimples usually result from a small variation in the anatomy of the zygomaticus major, a muscle that helps pull the corners of your mouth upward when you smile. In people with dimples, this muscle can have an unusual split or attachment pattern. When they smile, the skin gets pulled inward at that spot, creating the familiar indentation.
Chin dimples have a different origin. They’re often associated with the shape and development of the underlying chin bone and soft tissues, producing the central cleft or crease.
Are dimples genetic?
Yes, to a degree—but the old idea that dimples are controlled by one simple “dimple gene” is probably an oversimplification. Their inheritance appears to be more complicated, and scientists don’t have a neat single-gene explanation for everyone who has them.
Dimples can also become less noticeable with age as facial tissues and muscle structure change.
Why do they disappear when you’re not smiling?
That’s part of the charm! A cheek dimple is often most visible when the facial muscles contract during a smile. When the muscles relax, the skin may smooth out and the indentation can become barely visible.
So the “mystery” is essentially a tiny anatomical variation: a different arrangement of muscle and connective tissue creates a little tug on the skin whenever you smile. What looks like a decorative mark is actually a fascinating consequence of how your face is built.