The Exact Reason Your Lip Injections Look Fake, Study Finds

According to a recent study, medical experts have determined the difference between good and bad lip injections — and the results are surprising.

By Sarah Kinonen. Photos: Getty Images.

Thanks to Kylie Jenner, we all know what lip injections look like, or at least, have a relatively decent idea of how pout enhancement can alter one's appearance. But, according to a study by JAMA Facial Plastic Surgery, doctors have recently come together to determine the exact amount of filler deemed too much for lip augmentation. (Lip augmentation is a cosmetic enhancement procedure that adds volume to the lips via injectable fillers, such as Juvéderm, Volbella and Ultra.) Because sometimes, without a fixed amount, post-augmentation puckers can look far too artificial than attractive (or so they say).

For the April study, medical experts asked 98 volunteers (76 females and 22 men) to review photographs of a female model's lips, which were digitally altered in five sets of features — the upper lip, lower lip, upper and lower lips, and shape of the Cupid's bow. Over a two month time period, participants were asked the view the photographs — in random order — via an online survey with two questionnaires for each photo. Each questionnaire required participants to say whether or not they believed the lips appeared to have received cosmetic enhancement, and if they considered the lips to be either attractive and natural, or artificial and unnatural.

The results? Well, to be honest, not all that surprising. The study found that 50 percent of participants believed that the lips were treated if the ratio of lower to upper lips was less than 0.92 or greater than 1.48; while 50 percent also perceived the lips to be artificial if the ratio of lower to upper was either less than 0.85 or greater than one. Which is to say, the human eye is a brutal critic — and there is a narrow window within which lips look plausible. If the lower lips look either too big or too small in relation to the upper lip, the overall effect can look false. And there were a few more interesting — and perhaps more relatable — findings. Enhancing the upper lip alone was more likely to trigger the eye's artificial meter, while enhancing both lips was more believable. And any alteration at all to the Cupid's bow had the narrowest margin for error, so to speak.

Science speak aside, this all means that the study's major takeaway is that the old adage "less is more," very much applies to lip augmentation procedures. "The best way to give a patient natural result is to enhance what they already have, rather than trying to create something new," says New York City-based dermatologist Joshua Zeichner. "This usually is achieved by treating both the upper and lower lips."

Zeichner adds that another key component of the study's results found that if treatment affected the Cupid's bow — the "V" shape at the center of the upper lip — participants were more likely to associate the lips with artificial enhancement. "A natural-appearing lip has a balance of all the three components, generally with a larger lower lip compared to the upper lip,"says Zeichner. "However for every rule, there is an exception to the rule, and there are many patients who have been actually given an equal-sized upper and lower lip." Not all lips are made equally, so what size looks best on you is for you — and your medical professional — to decide.

This story originally appeared on Allure.

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