Move over thigh gaps and exposed collarbones, there's a new viral body-shaming trend in town: Barbie feet.

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The newfound "Instagram epidemic," as Who What Wear UK describes it, is a pose models and bloggers and stars alike have adopted to appear thinner and taller.

“While Barbie's plastic feet are permanently moulded into a pointed position, Instagram pros are whipping out the pose when they want to elongate their legs in photographs,” the fashion site reported.

If you really want to master the seemingly uncomfortable Barbie feet look, "act like you're wearing an invisible pair of high heels, even though there's nothing but air under your arches. From the front, it can be hard to tell you're doing anything at all, but from the side, you can see that you're balanced solely on the ball of your foot.”

In America, this obsession with thinness dates back to the mid-1800s, when dieting trends started gaining mainstream attention.

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One of the first diets was introduced in the 1840s by a Presbyterian minister named Sylvester Graham, historic gastronomist Sarah Lohman told Live Science.

He preached "spices, stimulants and other overindulgences lead to indigestion, illness, sexual excess and civil disorder" and urged his "Grahamites" to eat bread made of coarse graham flower, vegetables and to drink water.

“By the end of the century, Americans had fallen headfirst into this battle against fat," Lohman said. “Between 1890 and 1920 specifically, America's image of the ideal body completely changed from one of healthful plumpness to one where fatness became associated with sloth. There was a surprisingly strong current of disgust against people who were perceived as obese.”

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She cites the departure of the corset, industrial revolution’s introduction to standardized dress sizes, urbanization’s creation of sedentary jobs and advancements in food science as key factors leading to the obsession.

Years before Mattel, Inc.’s first Barbie came into the American market in 1959, counting calories and dieting (or feeling guilty about not doing either) had become the norm.

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The doll's body proportions have been deemed "unrealistic" and "impossible" to attain by many. If she were a real woman, "she would stand 6 feet tall, weigh 100 pounds, and have a 39-inch bust, a 19-inch waist, and the hips of a prepubescent boy," Samantha Olson of the Medical Daily reported in 2014. "In this impossible quest to reach Barbie's unattainable measurements, many girls have developed what is known as "The Barbie Effect."

Though recent body-positive movements have given way to Mattel's new curvy, petite and diverse Barbie dolls, social media (and Instagram in particular) has added unrealistic expectations and feelings of inadequacy in women and girls, according to a #StatusOfMind survey from the United Kingdom's Royal Society for Public Health.

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“Instagram easily makes girls and women feel as if their bodies aren’t good enough as people add filters and edit their pictures in order for them to look ‘perfect’,” one survey respondent wrote.

Viral trends like Barbie feet, the collarbone challenge, bikini bridge and a continuing obsession with chasing Instagram-inspired perfection continues to lower women's self esteem and body satisfaction, Australian psychology professor Marika Tiggeman told INSIDER.

“In daily life these small, one-off effects [on body image] are likely to cumulate to a much bigger effect,” she said.