Your Mole May Actually Be a Third Nipple — Here's How to Tell

Yup, even Harry Styles has an extra nipple. (Well, two extra, to be exact.) (GIF: YouTube)

Third nipples sound like something out of a sci-fi movie, but they’re more common than you’d think. Mark Wahlberg, Lily Allen, and Joanna Krupa all have one, and One Direction’s Harry Styles actually has two extras.

Experts say supernumerary nipples, as they’re known in the medical community, are actually pretty common (the National Institutes of Health cites data that says they can occur in as many as one in every 500 people). In fact, you might have one and not even know it.

“A lot of people have them but never give them a second thought,” board-certified plastic surgeon Anne Taylor, MD, chair of the American Society of Plastic Surgeons Public Education Committee, tells Yahoo Health. “They think they’re a mole.”

Mark Wahlberg is in the three-nipple club. (Photo: Corbis/infusmi)

Of course, there are a few distinctions between a regular mole and an extra nipple. Three ways to tell:

  1. Third nipples have nipple-like qualities. “It has a little bump in the middle like a nipple would have, and may have some hair around it,” Alan Menter, MD, chairman of the division of dermatology at Baylor University Medical Center in Dallas, tells Yahoo Health.

  1. They’re found directly down from your nipple on what’s known as the “mammary line.” This starts around your collarbone, goes through the normal nipple on either side, and down into your groin. Any “mole” down that line is worth a second look. 

  1. They may actually have some breast tissue underneath. Women who are pregnant can notice swelling behind a third nipple, Menter says, and in rare cases may even produce milk from that nipple.

But how can an extra nipple go undetected?

It’s because they’re usually tiny, often just a centimeter in diameter, says Menter. And they don’t just pop up out of nowhere — we’re born with them. “When we’re embryos, there are a lot of things that form and then regress,” explains Taylor. Supernumerary nipples can form in utero and just never fully regress on some people.

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Research has found that people can have up to eight extra nipples, but just one extra is the most common. There’s also a gender and race divide with third nipples, per a paper published in the journal Pediatric Dermatology: Men are more likely to have them than women, and they’re more common in African-Americans than Caucasians.

Extra nipples are mostly harmless, says Norman Rowe, MD, a board-certified plastic surgeon practicing in New York City. But, in the rare case where there’s a breast underneath, it must also be monitored for breast disease, he says. Research published in Dermatology Online Journal also found a link between extra nipples on men and an increased risk of developing cancers of the prostate, bladder, kidney, testicles, and penis.

Related: 10 Common Symptoms That Can Be Cancer

Have a third nipple and don’t want it? It’s easily removed with a quick procedure in a dermatologist’s or plastic surgeon’s office.

However, Taylor says that while most people are surprised to learn they have an extra nipple, they quickly brush it off: “A lot of times the patient’s like, ‘I really don’t care.’”

Of course, you could take the same stance as Wahlberg, who told Rolling Stone, “I’ve come to embrace it. That thing’s my prized possession.“

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