A new study from Flinders University in Australia suggests that a large portion of the content posted under hashtags like "healthy lifestyle," "nutrition," and "clean eating" on TikTok and Instagram may not simply be promoting healthy habits, but also reflects patterns associated with orthorexia nervosa, an excessive preoccupation with eating foods viewed as "healthy" or "pure," combined with rigid dietary rules and avoidance of foods labeled as unhealthy.
اضافة اعلان
The researchers found that many posts link health to physical appearance, impose restrictive dietary rules, and morally divide food into "good" and "bad," at a time when unqualified influencers dominate most of the health content users encounter.
A Study of 300 TikTok and Instagram Videos
The study, titled "Eat Like Me = Look Like Me: A Content Analysis of Healthy Lifestyle, Nutrition, and Clean Eating Content on Social Media," was conducted by researchers Katie Purtious, Ivanka Prichard, and colleagues (listed as Eva Kemps and Ashleigh Powell among the authors). It was published as an original open-access research study in the Journal of Technology in Behavioral Science on July 22, 2026.
The data collection itself, however, took place roughly a year earlier: the team searched TikTok and Instagram between May 25 and 27, 2025, using three hashtags: #healthylifestyle, #nutrition, and #cleaneating.
The researchers collected the first 50 videos that appeared for each hashtag on each platform, bringing the total sample to 300 videos: 150 TikTok videos and 150 Instagram Reels. Average video length was 26.8 seconds on Instagram and 25.7 seconds on TikTok.
The researchers used dedicated accounts and hashtag-based search to limit the effect of algorithmic personalization, and cleared their Instagram search history before collecting data.
What Did the Study Examine?
The study focused on content aimed at women and featuring female creators, comparing TikTok with Instagram, and content produced by qualified professionals versus content posted by unqualified influencers.
The researchers sought to determine how widespread certain patterns associated with orthorexia nervosa were, including food restriction, moral classification of food, linking health to appearance, and rigid eating behaviors, in addition to assessing the accuracy of the health information posted.
To ensure consistency in the content analysis, a second researcher independently coded 20% of the videos. Inter-rater agreement reached 0.88 on Cohen's Kappa, indicating a very high level of agreement.
67% of Videos Focus on "Clean Eating"
Results showed that 67.3% of videos across both platforms focused on "clean" or healthy eating, while 31.3% focused on controlling macronutrients such as protein, carbohydrates, and fat.
Promotion of supplements or so-called "superfoods" appeared in 75.3% of videos, while healthy eating was presented in an aesthetic, idealized way in 49.3% of the content.
About 28.7% of videos imposed rules or restrictions around food, while fear-based messaging about certain foods or encouragement to avoid them appeared in 16% of clips. Additionally, 19.7% of videos used language that morally classified food.
Instagram leaned more toward presenting a healthy lifestyle as a status symbol, appearing in 36% of its content compared to 24.7% on TikTok.
Diets and Weight Loss
36.3% of videos showcased specific dietary patterns. Fitness-related diets were the most common, at 19.7%, followed by weight-loss-related diets at 10.7%.
Calorie counting appeared in 8.3% of videos, while only 7% contained actual food preparation instructions.
TikTok was more inclined than Instagram to present diets aimed at improving so-called "wellness," with such messaging appearing in 16% of TikTok videos.
By contrast, content promoting dietary flexibility was not widespread: eating for enjoyment appeared in 20.3% of clips, foods eaten for pleasure or in moderation in 17.7%, balanced nutritional messaging in only 15%, anti-diet-culture advice in 13.7%, and content about recovery from eating disorders in just 2.7%.
Physical Appearance Featured Heavily
The study found that 63% of all videos included some form of turning the body into a visual object or placing exaggerated focus on it.
The gap between platforms was clear: this appeared in 78% of Instagram content compared to 48% on TikTok.
Similarly, 46.7% of Instagram videos placed exaggerated focus on specific body parts, compared to 30.7% on TikTok.
The idealized lean or muscular body standard appeared among 70.7% of people featured on Instagram, compared to 47.3% on TikTok.
Also on Instagram, 31.3% of creators directly linked their athletic appearance to specific dietary choices, compared to 16% on TikTok.
Exercise Also Becomes an Appearance Standard
People exercising appeared in 34.7% of Instagram videos, compared to 21.3% of TikTok videos.
Strength training appeared more often on Instagram, at 26.7% versus 8.7% on TikTok, while cardio was more common on TikTok, at 17.3%.
Additionally, 8% of videos framed exercise as a moral obligation, and compensatory or excessive exercise appeared in about 10.1% of the content.
Instagram leaned more toward presenting fitness in an idealized, aesthetic way, at 24.7% compared to 14% on TikTok.
78% of Creators Are Unqualified
One of the study's most notable findings concerns the source of the information itself. Of the creators analyzed, 78% held no recognized qualifications in health, nutrition, or fitness, compared to just 22% who were qualified.
The researchers classified 68% of the information posted across both platforms as misleading or deceptive.
Content rated as reliable made up only 15.3% on TikTok and 11.3% on Instagram, while content deemed harmful appeared in 5.7% of videos on both platforms.
The gap between qualified and unqualified creators was substantial: qualified creators provided accurate information in 45.5% of their content, compared to just 4.7% for unqualified influencers.
By contrast, 75.2% of unqualified influencers' content was classified as misleading or deceptive, compared to 40.9% for qualified creators.
"Eat Like Me to Look Like Me"
The researchers noted a recurring implicit message: that following the same diet shown by a creator would lead to achieving the same physical appearance.
The study points out that this approach ignores fundamental differences between individuals, including genetics, lifestyle, and personal and cultural circumstances, and presents health as though it were simply the result of choosing one single "ideal" diet.
The researchers also found examples of rigid rules, such as fixed daily protein targets, calls to eliminate sugar entirely, or requiring protein at every dinner. Fear-based messaging about certain foods or ingredients also appeared.
What's the Connection to Orthorexia Nervosa?
Orthorexia nervosa differs from a normal interest in healthy eating; it involves an excessive preoccupation with food "purity" and strict adherence to specific dietary rules, sometimes to the point of eliminating entire food groups or avoiding social occasions for fear of eating foods considered "impure."
The study notes that much of the health content on both platforms reflects similar elements, such as dietary rigidity, moral classification of food, and linking dietary discipline to an idealized appearance.
However, the study does not claim that watching these videos directly causes orthorexia; it is a content-analysis study, not an experiment measuring causal effects on users. The researchers' conclusion is that both platforms may repeatedly expose users to messaging that aligns with thought patterns associated with the disorder.
Instagram More Focused on the Body, TikTok on "Wellness"
The researchers found differences in how health was presented across the two platforms. Instagram was more focused on idealized bodies, muscles, body parts, and appearance tied to food and fitness.
TikTok, by contrast, leaned more toward framing health under a general "wellness" umbrella, though it still contained a substantial amount of rigid dietary messaging and inaccurate information.
Overall, the study concluded that both platforms heavily expose users to content linking "clean" eating, dietary discipline, and physical appearance, with the bulk of this content coming from people without specialized health qualifications.
Study Limitations
The researchers acknowledged several limitations. The sample focused on content aimed at women and female creators, so the findings cannot be directly generalized to men or to all demographic and cultural groups.
The dominance of unqualified influencers in the sample also made the numerical comparison between them and qualified professionals less balanced. Assessment of qualifications relied on publicly available information in profiles or found via Google and LinkedIn searches.
Additionally, some content classification processes, such as determining whether a behavior was "healthy" or "unhealthy," or whether information was misleading, involved a degree of human judgment, despite the use of a defined coding system and a high level of agreement among researchers.
The researchers concluded that health and nutrition content on TikTok and Instagram frequently reflects dietary rigidity, moral classification of food, and the linking of health to physical appearance, alongside widespread misinformation from unqualified influencers. They called for greater presence of experts and evidence-based health information on social media platforms.
Resource: Al-Ghad.
