Abstract
<sec> <title>UNSTRUCTURED</title> <p>Background: Social media is a primary channel for health information and misinformation, but the prevalence of non-evidence-based information (NEBI) across languages and platforms is poorly characterized. Aims: To determine NEBI prevalence in cardiovascular health across English, Hindi, and Spanish on major social media platforms and search engines. Methods: This cross-sectional study evaluated 14,901 posts on Facebook, YouTube, Instagram, TikTok, X, Google, and Bing, using specified search terms replicating typical user searches. Results: Overall NEBI prevalence was 59.0%. NEBI rates were highest on Instagram (76.3%), TikTok (74.7%), and Facebook (69.2%), and lowest on Bing (43.1%), YouTube (43.2%), and Google (45.6%). By language, English had the highest rate of NEBI (73.5%), followed by Hindi (56.6%) and Spanish (45.5%). Independent users produced NEBI at significantly higher rates (65.8%) than hospitals (25.5%) or governments (30.7%). NEBI received fewer views and subscribers than evidence-based content but generated more likes and used emotionally charged language. Predominant NEBI topics across languages included tobacco, blood pressure, blood sugar, and weight. Conclusions: Nearly 60% of online cardiovascular content is non-evidence-based. Significant variations across platforms, languages, and topics expose billions of daily users to potentially harmful health information.</p> </sec>