Mind the gap. The latest beauty trend amongst teenage girls and young women around the globe is the desire to achieve a so-called “thigh gap,” a space between the upper thighs that’s visible even when standing with your legs straight and your knees together. It’s a rapidly growing fad that has inspired countless websites, how-to articles, Twitter posts and Tumblr photos.

But why would girls suddenly want their legs to look like football goalposts? The movement seems to have been inspired by waifish 20-year-old British model and current fashion “it girl” Cara Delevingne, whose physique is so popular that someone created a Twitter account for her thigh gap. The account might be tongue-in-cheek, but the arbitrary redefinition of beauty and fitness that is the thigh gap has scores of teens to 30- or even 40-somethings vowing to stop at nothing to achieve it. And this is where the danger starts.

From a medical standpoint, most women trying to attain a thigh gap are fighting an unwinnable war, because it’s a physical attribute that has more to do with bone structure (particularly pelvic size), metabolism, ethnicity and in some cases, Photoshopping than it does diet and exercise. But a lack of the necessary genetics isn’t stopping those obsessed with getting a gap, exposing them to medical risks like eating disorders, physical injury from over-exercising and even unnecessary cosmetic surgery to suck fat from their thighs.

There’s a reason why thigh gaps are so much more prevalent in pre-pubescent girls than they are in adult women: their bodies haven’t developed yet. The skinny frames that are commonplace for 8-year-olds aren’t healthy for adults. In females, puberty causes several body changes that run counter to maintaining a thigh gap; specifically, fat tissue increases in the hips, thighs and buttocks, and the pelvis widens to make it easier to give birth. So, trying to develop a space between the thighs is fighting against nature, and the adults who are able to achieve it are the ones who have the specific genetic build and the ones who have the unhealthy and potentially deadly lifestyles necessary to overcome biological progress. Now, you have to ask yourself: is looking like Spongebob Squarepants worth the risk?

(Sources: ThighGapHack.com, MatchstickMolly.com, Twitter, Tumblr, Models.com, New York Daily News, The Daily Mail, Your Daily Record, News.com.au)