by In some cultures, dimples are seen as a sign of beauty or even good luck. But what causes moles, and why do some people have them and others not?
Dimples are small natural lines in the skin. About 1 in 5 people have clefts, according to a 2019 meta-analysis in The Journal of Craniofacial Surgery (opens in a new tab). They are most commonly found on the cheeks but can be located on other parts of the body, such as the chin and lower back.
Live Science looked at how these indentations form and whether they can disappear over time.
How dimples are formed
Cheek dimples are created by an anatomical change in a facial muscle called the zygomaticus major (ZMj), according to a 2019 meta-analysis in The Journal of Craniofacial Surgery. The ZMj pulls the mouth up and down, creating facial expressions of pleasure or pain and everything in between.
In people with clefts, however, the zygomaticus major is divided into two muscle groups – one above the corner of the mouth and the other below. This is called a double or bifid ZMj. When the skin moves over the two muscle groups, it creates an indentation, otherwise known as a dimple.
Dimples are passed on genetically, although it is not entirely clear how. According to a 2015 review in the Innovative Journal of Medical and Health Science (opens in a new tab)people with one impaired parent have a 25% to 50% chance of having the indentation, and people with two impaired parents have a 50% to 100% chance.
“The question of genetics in dimples has been poorly researched to date, and very little work has been done in the field,” Ross Elledge (opens in a new tab), a consultant oral surgeon and falconist in the UK, told Live Science by email. “The overriding theory is that inheritance is autosomal dominant – only one of a pair of genes needs to code for the presentation of the impulses and that this gene can be inherited from either the mother or the father.”
Ross Elledge
Ross Elledge is a consultant oral and maxillofacial surgeon and honorary senior clinical lecturer in the UK, with private clinics including Birmingham, Solihull and London. He is also an honorary consultant on an oral and maxillofacial surgery contract with Sandwell and West Birmingham Hospitals NHS Trust.
According to MedlinePlus (opens in a new tab)at the National Library of Medicine, little research has been done to explore the genetics of impales and it is not known which gene or genes may be involved.
While many people are born with dimples throughout their lives, some people are born with dimples that disappear as they age, according to the Genetic Science Learning Center. (opens in a new tab). Others develop dimples later in childhood.
One possible explanation for the impermanence of some dimples is fatty deposits in the cheeks during childhood, according to a 2015 review (opens in a new tab) mentioned earlier. People lose fat in this area as they age, and the facial muscles stretch and stretch, causing the eyebrows to disappear.
“Fat in the area may remodel over time, which may lead to larger, or smaller, dimples as the face ages and remodels,” Elledge said. “Therefore, some people will ‘lose’ their impulses as they age, while in others, they may be more significant.”
Where can you get mats?
Cheek dimples can form on one or both cheeks, but individual dimples are rare, according to a 2015 review. (opens in a new tab). They can vary in depth and size, and usually sit on the side of the mouth, appearing deeper when people smile or laugh.
Dimples can form on parts of the body other than the cheeks, with some types more common than others.
Sometimes called a cleft chin, chin dimples are not formed in the same way as cheekbone divots. Instead, they are a Y-shaped indentation that occurs when the right and left sides of the jawbone or jaw muscle do not fully meet during development in the womb. Just like cheekbones, these permanent facial features are thought to be genetically inherited from one or both parents.
Back dimples, also known as ‘dimples of Venus’ in a similar way to cheek dimples, are formed when a short ligament runs from part of the hip bone to the skin on the back. This pulls the skin in, creating a dimple. Buttocks are usually located on the lower back, just above the buttocks. Like other skin moles, back moles are thought to be genetic, but there isn’t enough research to be definitive on the matter.
So is it more likely that someone else will have moles on the body if they have moles on the cheeks? “There is no clear genetic or anatomical basis for dimples in other areas of the body to follow naturally from dimples on the cheeks,” said Elledge. “Therefore, when you have cheek moles, you are no more or less likely to have moles anywhere else on your body.”
