The Ins and Outs of Belly Buttons

Few parts of the human body are as perplexingly useless as the belly button. What is it for, exactly? The appendix is a remnant of some long-ago useful digestive organ, the coccyx is a remnant of a mammalian tail, but belly buttons are just, well, there. Humans always have and always will have navels, unless evolution comes up with some superior method of gestation and childbirth. Until that happens, we’re stuck with the weird knobby divots in the middle of our abdomens. But just what are belly buttons, anyways?

Scarred for Life

Belly buttons aren’t evolutionary leftovers. Technically, belly buttons are scars. They’re the remnants of the umbilical cord and placenta, which connect a baby to its mother while in utero. Once the baby is born, the umbilical cord is severed and tied off, scar tissue forms in the place where the umbilical cord attached to the abdominal wall hair transplant price, leaving us with the strange formation we know as a belly button.

All mammals have belly buttons, from mice to whales, because all mammals give birth to live young. Even animals born in litters, like dogs and cats, have their own placenta, so they have a belly button, too. Rather than being the noticeable marks that they are on humans, animal navels tend to be smoother and flatter, often nothing more than a thin line. Plus, the fact that they’re covered with fur tends to make them harder to see.

Are You In or Out?

About 90 percent of humans have concave belly buttons, or “innies.” In concave belly buttons, the scar tissue develops inward, growing toward the abdominal wall. Convex navels, or “outies,” protrude away from the stomach, with extra scar tissue causing them to stick out. Infants start life as outies and in the first few months of life, the remnants of the umbilical cord shrivel and fall off, forming the navel the child will have the rest of her life. No one knows why some navels become concave and some become convex. It’s not a genetic trait; it’s simply random chance. We do know a few things about them though—they have nothing to do with the skill of the doctor severing the placenta or how the cord is cut, since that’s done several inches away from the body. A person’s belly button also has no bearing on his health or vitality.

Sometimes, an outie is not really an outie. A protruding navel can actually signal an umbilical hernia, which is not uncommon in infants. If the abdominal muscles don’t seal off properly after the umbilical cord is cut, part of the intestine can force its way through the opening. Most umbilical hernias close up on their own by about age one, although some take a bit longer to heal, and could potentially require minor surgery. There’s an easy way to tell whether a baby’s protruding navel is a hernia or just a standard-issue outie: hernias only protrude when a baby cries and normal outie navels are always protruded.

During pregnancy, the pressure from the growing fetus can cause a woman’s innie to pop out and become an outie, but after childbirth, most women find that their navels return to their original configuration. Not all women experience changes with their navels, but it’s a perfectly normal occurrence during pregnancy Unfortunately, a popped-out navel isn’t like the button on a turkey, and doesn’t mean the baby is ready to be born.

Missing a Button?

Since every human develops with a placenta and umbilical cord, every human must have a belly button, right? Not entirely true. In fact, it’s possible for people to be born without a traditional belly button. When infants need surgery for an umbilical hernia, the operation often leaves behind a smooth, flat indentation where the belly button should be. There are also several genetic disorders that require immediate surgery, such as gastroschisis, where the intestines and other internal organs are pushed outside of the body. Infants with these disorders undergo surgery in their first hours of life, and they have scars where their navels would otherwise be.
Czech supermodel Karolina Kurkova is notably navel-less. She had an operation as an infant, most likely to correct an umbilical hernia, and as a result, she has a smooth indentation on her abdomen, but no navel scar. It’s noticeable when she walks in runway shows, but in print campaigns, an airbrushed belly button is added to her photos.

Navel Perfection

Some people are so deeply insecure about their belly buttons that plastic surgeons now offer procedures that can change the size or shape of the navel. Umbilicoplasty is a relatively short and simple procedure—it doesn’t even require general anesthesia—that can reshape the belly button into something more desirable. Many people who undergo the procedure are uncomfortable with their outies while wearing swimwear or revealing summer clothes. People who don’t have traditional belly buttons sometimes want to create a cosmetic one to feel more “normal,” and some women like to recreate the pre-pregnancy look of their navels. A study at the University of Missouri found that vertically oriented navels with a T-shape were considered the most attractive. Large, deep, or protruding belly buttons were found to be the least desirable. The U.S. isn’t alone in its fascination with belly buttons. In 1995, the Wall Street Journal reported that navel reconstructions had increased in Japan by 375 percent.

Umbilicoplasty isn’t the only surgery involving the navel. New techniques are also utilizing the belly button as a way to perform abdominal surgery without leaving scars. It’s now possible to perform breast augmentations, kidney operations, and other abdominal procedures by entering the navel to minimize scarring.

Belly buttons may not serve much of a purpose, but we still manage to remain fascinated by their oddity, wearing revealing fashions to show them off as well as piercing and tattooing them. They may not reveal much in the way of health or fertility, but regardless of whether they’re innies Honorary Fellowship, outies, or even “smoothies,” at least they prove that we’re not aliens.