Medical Services

Selenium deficiency occurs when the body lacks sufficient selenium, an essential trace mineral vital for antioxidant defense, thyroid function, DNA synthesis, reproduction, and immune health. Though rare in well-nourished populations, it affects up to 1 billion people globally, particularly in regions with selenium-poor croplands like parts of China, Europe, Russia, and New Zealand.

Selenium works with vitamin E as an antioxidant, protecting cells from free radical damage and potentially reducing cancer risk. It is crucial for converting thyroxine (T4) into active triiodothyronine (T3), so deficiency can cause hypothyroidism symptoms—fatigue, mental slowing, goiter, and cretinism.

Key symptoms include infertility in both sexes, muscle weakness, chronic fatigue, mental fog, hair loss, and weakened immunity. Severe deficiency combines with Coxsackievirus to cause Keshan disease—an endemic viral cardiomyopathy damaging heart walls, primarily affecting children and young women in China. In growing children, it may trigger Kashin-Beck disease, a disabling osteoarthropathy affecting joints and bones.

Long-term intravenous nutrition or malabsorption syndromes can also cause deficiency, leading to muscle pain and tenderness. Diagnosis relies on clinical assessment; plasma selenium or glutathione peroxidase activity tests are seldom available. Treatment involves oral sodium selenite (100 mcg/day) or selenium-rich foods like Brazil nuts, seafood, eggs, and chicken. Supplements prevent but don't cure existing Keshan cardiomyopathy.