What is the function of Selenium? As a mineral of dietary importance, selenium has powerful antioxidant and anti-inflammatory effects. Selenium protects cells from free radical damage and helps reduce joint inflammation as well. In addition to this, selenium regulates the activity of the thyroid gland by stimulating thyroid hormone production.
Selenium deficiency symptoms include: muscle weakness and muscle aches and pain, discoloration of hair and nails, white spots on nails. Observation: Brazil nuts are actually the richest source of selenium, codfish coming second. However, Brazil nuts contain such high quantities of selenium that one can easily have a much higher intake than recommended.