Dimples form because of a small variation in the structure of a facial muscle. The major cheek muscle, called the zygomaticus major, normally runs in one continuous band from your cheekbone to the corner of your mouth. In people with dimples, this muscle is either shorter than usual, split into two separate bundles, or has a fork-like division partway along its length. When you smile, the split or shortened muscle pulls the skin inward at the point of the gap, creating that small visible indent.
An estimated 20 to 30 percent of people worldwide have cheek dimples, making them common enough to be familiar but uncommon enough to stand out.
What’s Happening Under the Skin
The indent you see isn’t a hole or a missing piece of tissue. It’s a tethering point where muscle fibers attach to the inner surface of the skin rather than gliding freely beneath it. In a typical cheek, the muscle slides under the skin as it contracts, pulling the corner of the mouth upward in a smooth motion. When the muscle has a structural variation, part of it tugs directly on the skin’s underside, creating a small depression right at that anchor point.
This is why dimples only appear during certain expressions. At rest, the skin sits flat because the muscle isn’t pulling on it. The moment you smile or laugh, the contraction activates the tether and the dimple appears. Some people have dimples on both cheeks (bilateral), while others have one on just one side (unilateral). Unilateral dimples are actually more common, which makes sense given that the muscle variation doesn’t need to occur symmetrically.
Are Dimples Genetic?
Dimples have long been taught in biology classes as a textbook example of a dominant genetic trait, meaning you’d only need one copy of the relevant gene variant from one parent to develop them. The reality is more complicated. According to MedlinePlus, some researchers say there is no solid proof that dimples follow a simple inheritance pattern, and the specific gene or genes involved have not been identified.
What’s clear from observation is that dimples do run in families. If both your parents have them, you’re more likely to have them too. But there are plenty of cases where dimpled parents have children without dimples, and vice versa. This suggests the trait may involve multiple genes working together, or it may be influenced by developmental factors in the womb that aren’t purely genetic. The honest answer is that genetics almost certainly plays a role, but scientists haven’t nailed down exactly how.
Why Some Dimples Fade With Age
If you had pronounced dimples as a child that seem shallower now, you’re not imagining things. As the face grows and gains subcutaneous fat, the relationship between the muscle and the skin changes. The tethering point may become less pronounced as surrounding tissue fills in. In some people, dimples that were visible in childhood essentially disappear by adulthood. In others, they deepen or become more defined as baby fat recedes from the cheeks. Weight changes throughout life can also affect how visible dimples are, since fat distribution in the cheeks alters the surface contour.
Dimples Vary by Population
The prevalence of cheek dimples differs across populations. Data collected by Primal Pictures found that dimples were most common among an American subgroup at about 34 percent, followed by an Asian subgroup at 27 percent, and a European subgroup at 12 percent. These numbers come from specific study populations rather than comprehensive global surveys, so they’re rough estimates. Still, they confirm that dimples aren’t evenly distributed across all groups, which further supports a genetic component to the trait.
Chin Dimples and Back Dimples
Not all dimples share the same cause. A chin dimple, sometimes called a cleft chin, forms when the two halves of the jawbone don’t completely fuse during fetal development, leaving a small gap in the underlying bone that creates a visible crease in the skin above it. This is a different mechanism entirely from cheek dimples, which involve muscle rather than bone.
Back dimples, sometimes called the dimples of Venus, appear as two small indentations on the lower back, just above the buttocks. These are caused by a short ligament that connects the outer edge of the pelvic bone directly to the skin. Because the ligament is short and taut, it pulls the skin inward at that point, creating a visible dip. Back dimples are present from birth and don’t change much with facial expression or movement. They’re purely structural and are generally considered a normal anatomical variation.
Why Dimples Are Considered Attractive
Dimples have been considered attractive across many cultures for centuries, and there are a few theories about why. One explanation is rooted in social signaling: dimples make a smile more visually distinctive and easier to read from a distance, which could amplify the perceived warmth or friendliness of the person smiling. Another theory ties into neoteny, the retention of youthful features into adulthood. Dimples are associated with round, youthful faces, and features that signal youth tend to be rated as more attractive in studies of facial perception.
The cosmetic appeal of dimples has created a market for dimpleplasty, a procedure in which a surgeon creates an artificial tether between the cheek muscle and the skin to mimic a natural dimple. The procedure is relatively quick, but the results are permanent. Unlike natural dimples, surgically created ones may be visible even when the face is at rest, at least initially, because the scar tissue that forms the tether hasn’t yet softened.