evidence: Folk remedy of placing raw onions on feet to cure illness lacks scientific evidence [...] A post shared on Facebook on 27 December 2023 claimed that chopped raw onions absorb toxins and purify air. The post also claimed that placing sliced raw onions against the feet can alleviate symptoms of sinus infections including cough. According to the claim, putting onions against the feet allows for the antibacterial benefits of the onion to be delivered directly into the bloodstream. [...] Placing raw onions against the feet appears to stem from principles of reflexology, a practice that massages pressure points—often in the feet—to alleviate symptoms of certain ailments. However, research on reflexology is typically of poor quality. One systematic review analyzing effectiveness of reflexology in palliative care found weak support for its benefits[2]. Another systematic review found only low-quality evidence to support reflexology’s benefits for short-term pain and anxiety[3].