Hunky Zac Efron and Mark Wahlberg always look awesome shirtless. Thousands of women all over the world have never, ever noticed that these two A-listers have something in common (besides amazing abs). What is it? They both have an extra nipple!

We know that out of thousands of hopefuls, only a few actors make it to the same status as Zac and Mark. You actually have a better chance of making it as an actor or actress than being born with an extra nipple. According to Dr. Sandra Lee, an Upland, California based dermatologist, “It is not widely known, but about one in 50 women and one in 100 men have a third nipple. This goes by several names besides “third nipple.” It is a supernumerary nipple, accessory nipple, pseudomamma, polythelia, or polymastia. It is often not entirely developed as a fully functioning nipple. Sometimes it can be mistaken for a mole. The third nipple usually has no clinical significance as long as nothing else is wrong.”

Take a close look at the above photos. You’ve got to squint to see Mark and Zac’s extra accessory. While theirs are easily found (okay, if you look hard enough), they do not, ahem, work. Dr. Lee states, “They (the nipples) are not properly formed like normal nipples and can usually be found on an imaginary ‘milk line’ between the armpit and inner thigh. If you feel uncomfortable about yours, it’s probably best to speak to your dermatologist or general practitioner to determine whether surgery is needed.”

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From the looks of it, Zac Efron and Mark Wahlberg seem to be very comfortable with their extra nipple. If someone is not, getting rid of one is a simple office procedure! Dr. Less explains, “This should be able to be addressed very easily with excision utilizing local anesthesia in the office. In most cases the scar is very reasonable and much preferred to the appearance of the accessory nipples.”

Tell us: now that you know Mark and Zac have an extra nipple, do they seem extra sexy to you?

PJ Gach is Senior Editor: Style + Beauty at BettyConfidential.

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