Key Summary Five popular platforms, ChatGPT, Gemini, Meta AI, Grok and DeepSeek, were used for the study. They were asked questions across five categories - cancer, vaccines, stem cells, nutrition, and athletic performance. Reference quality was noted to be poor, with an average completeness score of 40 per cent. An analysis of five popular chatbots' responses to health and medicine questions shows that many of them were inaccurate and incomplete.