A study by researchers at the Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center has found that chatbots often offer "problematic" cancer advice. The study compared Google's chatbot Gemini, the Chinese model DeepSeek, Meta AI, ChatGPT and Elon Musk's AI app, Grok. The researchers found that nearly half of the bots’ responses were “problematic” and nearly 20.6% were highly problematic. This comes as social media promotes bogus treatments for cancer or other health problems, and as more people rely on AI for health advice, these findings could put patients' lives at risk. The quality of responses was generally similar among the bots, though Grok performed the worst.