Iron deficiency in women is common – and often underestimated. Due to menstruation, pregnancy, or breastfeeding, many women experience chronically low iron levels. In Switzerland, around one in five women is affected. Typical symptoms include fatigue, poor concentration, headaches, brittle nails, and pale skin. On social media – especially TikTok – a simple idea is currently trending: a small fish made of iron that is added to food or water while cooking and releases iron. But does it...