Study Reveals Limited Evidence in Online Nutrition Advice for Breast Cancer Patients

The researchers emphasized the importance of proper nutrition for recovery, noting that malnutrition is a significant risk, especially for cancer survivors. To assess online information, they searched eight platforms from January to April 2025—Facebook, X, Instagram, TikTok, YouTube, Pinterest, Google, and ChatGPT. Using search terms commonly used by non-experts, such as "breast cancer diet" and "cancer nutrition," they analyzed the top 10 results per term, yielding 387 unique pieces of content with 151 distinct nutrition claims.

An expert panel evaluated each claim against established Australian and international cancer nutrition guidelines. They found only 8.6 percent of claims were supported by strong evidence or guidelines, while another 4 percent were based on basic scientific facts. In contrast, 63 percent of claims had no supporting evidence, 20.5 percent had weak evidence, and 4 percent were contradicted by existing evidence. The quality of information varied across platforms, with TikTok and X showing particularly low reliability, as about 76 percent and 73 percent of claims on these platforms lacked evidence or had contradictory information. Google and ChatGPT offered the best performance but still exhibited poor information quality overall.

The study also analyzed the types of content creators. Personal accounts, including influencers and cancer survivors, accounted for 35 percent of the content. Health professionals made up 33 percent, and groups and organizations, including nonprofits and online shops, represented 32 percent. Although health professionals shared a third of the content, they contributed fewer claims than organizations. Claims from health professionals were consistent with evidence 29 percent of the time, compared to 24 percent from personal accounts and organizations. However, this difference was not statistically significant, indicating that non-evidence-based information is prevalent across all content types. The researchers noted the challenge of verifying the qualifications of individuals presenting themselves as health professionals online.

To improve the situation, the study suggests establishing a standard system for identifying qualified health professionals, alongside media literacy campaigns and increasing access to reliable, evidence-based information online.

Senior author Associate Professor Tania Crotti underscored the need to differentiate between reliable and unreliable sources, stressing that bad advice could lead to malnutrition. The research team recommends patients consult the Cancer Council's guidance, which advocates for a diverse array of nutritious foods from all five food groups and encourages personalized nutritional advice tailored to individual care.