Selenium is an essential trace mineral that plays a critical role in overall health. It acts as a potent antioxidant, protecting cells from oxidative stress and supporting immune function. Selenium is important for thyroid hormone metabolism, which regulates numerous bodily functions and energy levels. Adequate selenium intake is linked to reduced risks of certain chronic diseases, including cancer. Foods rich in selenium include nuts, fish, and whole grains. Ensuring sufficient selenium levels can contribute to long-term health and wellness.