Selenium: When a Good Nutrient Goes Bad

Selenium (Se) was highlighted as an essential nutrient necessary for metabolic functions, with deficiencies leading to severe diseases like Keshan and Kashin-Beck diseases. While adequate Se intake could prevent certain cancers and diabetes, excessive Se was toxic, causing symptoms like hair loss and cardiovascular issues. Environmental Se levels were rising due to human activities, posing ecological risks, as seen in fish and bird populations in the U.S. The dual nature of Se, beneficial in proper doses but harmful in excess, underscored the need for careful management and recovery of Se resources. The document emphasized moderation in Se supplementation and the importance of integrated environmental assessment and management of Se.