evidence: A Facebook reel posted in May 2024 claimed that "charcoal absorbs and neutralizes poisons", drawing more than 1.3 million views to date. The claim was made by naturopath Barbara O’Neill, who has promoted unsubstantiated and potentially harmful health claims. Science Feedback debunked some of O’Neill’s claims in earlier reviews. [...] O’Neill’s claim that charcoal can be used to treat diarrhea, even in infants, isn’t substantiated by evidence. The U.S. National Center for Complementary and Integrative Health states that "No solid evidence supports claims that activated charcoal helps with [traveler’s diarrhea], bloating, stomach cramps, or gas". It also added that children shouldn’t be given charcoal. However, O’Neill’s claim that "charcoal absorbs and neutralizes poisons" is somewhat accurate, although it exaggerates the effectiveness of charcoal and lacks important nuance. In fact, misunderstandings over activated charcoal’s effects have led it to be wrongly touted as a way to "detox". We explain more below.