Getting fitness tips on social media can be harmful — but it doesn't have to be

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Tripods and cameras are scattered between the weights and benches in a Mississauga gym. It's common to find fitness influencers at First Health Club — recording videos of themselves pumping iron to post on social media. 

Among them is Chelsey Berestecki, 25, a young mom who only started posting fitness content on TikTok and Instagram a few months ago, after years of consuming such content while she tried to lose weight. 

"When I had my son in 2017, I gained a lot of weight with the pregnancy. I was 260 pounds," she said. "Over the past four years, I've lost over 100 pounds." 

"I would look at TikTok influencers in the fitness industry and kind of ... feel like that's the kind of life I want to live." 

It's a feeling that she says often pushed her to eat healthier and go to the gym, even when she didn't want to.

Only a few months since she's started posting, she already has over 8,000 followers — and growing — on TikTok. 

While it's been positive for her, online fitness content often has negative messages. Posts can be misleading. At worst, they can actively cause harm, whether through encouraging extreme dieting or recommending exercises that are not safe for everyone.

Despite the growing popularity of fitness influencers, their health impacts have not been well researched. Burgeoning studies are now starting to fill in the blanks — and even offering up solutions. 

A recent study out of the journal Body Image gives us one preliminary look. After examining 200 videos from popular TikTok fitness hashtags, like #fitness, #gymtok, #fittok, Australian researchers found 60 per cent of videos posted by fitness influencers presented misleading or harmful information. 

Authors say the vast majority of people posting the videos lacked important training on what they were posting about. The majority of videos also perpetuated negative messages, including sexualization, objectification (for both men and women), body shaming and excessive dieting.

"Promoting calorie deficits in general was quite a disturbing thing to see," said Samantha Pryde, the lead author of the study and a PhD candidate at Flinders University in Adelaide, Australia. She says many videos promoted extreme calorie deficits, below public health recommendations, for weight loss. 

"Ninety-five per cent of the people who were posting the videos didn't actually have relevant health, fitness or nutrition credentials," she said.

Social media makes it easier for viewers to feel like they have a personal connection to the influencer. That artificial closeness can make statements like "I did this to lose weight" or "here's what I ate in a day" sound like persuasive, personalized advice, says Pryde.