The University of Macau (UM) today (14 March) held a talk titled ‘Iron: The Troublemaker of Vitamin C in Cancer Therapy’ as the 11th talk of the UM Scholar Research Forum. Chen Xiuping, professor in the Institute of Chinese Medical Sciences, was the speaker. The talk attracted many UM faculty members and students, as well as teachers and students from secondary schools who joined the event through the internet. According to Prof Chen, vitamin C is a natural and promising anti-cancer drug as it has few toxic and side effects. It helps to absorb iron, an essential trace element for humans that was recently found to induce non-apoptotic cell death—ferroptosis, which is also considered a new anti-cancer strategy. However, his research team found that iron can significantly interfere with and reverse the anti-cancer effect of vitamin C. During the talk, Prof Chen discussed how iron becomes the troublemaker of vitamin C’s anti-cancer effect and the challenges it brings to anti-cancer research.