Selenium is a mineral found in the soil and available in foods such as mushrooms, Brazil nuts, eggs, sunflower seeds, liver, fish, turkey, chia seeds, and chicken breast. The selenium content of different foods vary by the mineral content of the soil, and deficiencies can occur in soil devoid of nutrients.
Selenium is a powerful antioxidant that combats oxidative stress in many areas of the body, including the brain. It is also needed for thyroid function, which regulates mood, energy and anxiety. Selenium increases glutathione, our master antioxidant, and therefore helps fight inflammation and may protect against heart disease, asthma, cancer and infertility. It also increases immune function by increasing interleukin 2, which is a cytokine that signals the immune system.
While deficiencies in selenium are rare, symptoms of inadequate selenium include hair loss, muscle weakness, brain fog, fatigue, and thyroid issues. Additionally, low levels of selenium have be associated with increased depression, anxiety and confusion.
The RDA of selenium is 55 mcg/day, but many experts aim for an intake of 70-90mcg for optimal antioxidant and immune response.