A Large-scale Observational Analysis of Social Media Data Reveals Major Public Misperception of the Attainability of Drastic Weight Loss by Dieting
2Institute of Endocrinology, Diabetes and Metabolism, Rambam Health Care Campus and Faculty of Medicine
3Bruce Rappaport Faculty of Medicine, Technion Israel Institute of Technology
Introduction:
Diet forums in social media websites provide an opportunity to glimpse the weight loss experience reported by tens of thousands of people.
Aims:
To compare weight information from individuals using different weight loss diet strategies in Reddit.
Methods:
We analyzed all postings with weight information from the six major Reddit weight-loss diet forums (“subreddits”) as reported by forum participants.
Results:
Data were collected from over 55,900 users. While average start BMI is in the overweight-obese range (26-34 kg/m2), average goal BMI was in the normal range (21.5-24.5 kg/m2) in all subreddits. There is a correlation between start BMI and goal BMI (R2=0.63, p<10-10) and between planned weight loss and reported weight loss (R2=0.56, p<10-10). Approximately 80% of forum participants reported over 5% weight loss. Reported weight loss was less than half of goal weight loss. Average reported weight loss and adherence were highest in the Keto and loseit subreddits. More upvotes and fewer downvotes were associated with higher reported weight loss in five of the six subreddits.
Conclusions:
Despite the need for cautious data interpretation due to self-selection of users who updated weight loss and possibility of unreliable weight reports, the study has interesting findings. Goal BMIs in the normal weight demonstrate a highly unrealistic perception, in a very large lay-public cohort, of the plausibility of losing all excess weight. Success in weight loss and maintenance in self-selected individuals who continued reporting weight for many months demonstrate the subjective value some people obtain from forum participation.
