While posting your weight loss journey or sharing your weekly grocery haul with friends and followers on TikTok and other social media may seem harmless, videos and hashtags like #WhatIEatInADay can actually help promote harmful eating behaviors in young adults, a new study published in PLOS One found.
Researchers at the University of Vermont analyzed 1,000 TikTok videos under the most popular hashtags related to body image and eating by using search terms like food, nutrition, weight and body image.
The study included 10 hashtags with at least one billion or more views. On the list were #WhatIEatInADay and #WeightLoss, which had 3.2 billion views and nearly 10 billion views respectively at the start of the study.
Less than 3% of the nutrition-related TikTok videos analyzed by the study's researchers were weight-inclusive. While the vast majority of the content was weight-normative which identifies weight as the main determinant of health.
Nearly 44% of the shared videos included content about weight loss; 20.4% portrayed someone's weight transformation.
Many of the videos also assigned good or bad labels to food which may "lead to development of eating disorders such as Orthorexia Nervosa, an eating disorder defined as the obsession with 'correct' eating and a fixation on foods' role in our physical health," the study says.
The harmful implications of weight-loss content could land squarely on the app's young — and vulnerable — demographic.
A third of TikTok's users in the U.S. were 14 or younger in 2020, according to the study authors.
The most concerning find in the study, is the amount of young women who interacted with weight loss content.
Over 60% of the videos were created by female-presenting people, and more than half were made by users in their teens or college-aged.
Researchers found that "young females who create and engage with weight or food-related content on TikTok are at risk of having internalized body image and disordered eating behaviors from other aspects of their lives."
The study also discovered that most nutrition advice for weight loss were provided by people who aren't experts.
"These types of videos likely spread and encourage harmful dieting interventions to a vulnerable audience that may not have strong media literacy skills," researchers wrote in the paper.
Just 1.4% of videos offering advice about nutrition were made by registered dietitians.
And TikTok's "For You" feature continually populates videos with related content that users typically engage with.
This means "if someone consistently engages with diet, weight loss, or food content, those videos will continue to appear unless the user actively selects a window labeled 'not interested,'" the study says.
But the study's authors believe that with the high volume of videos promoting diet culture on the app, professionals may need to step in.
They encourage health experts to keep in mind the type of content young people are interacting with and come up with ways to counter it to prevent harmful eating behaviors.
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