You might not know much about selenium and what it does, but trust me, you need it! Selenium is considered an essential nutrient, which means that it must be obtained from the diet. While only needed in small amounts (55 mcg per day for adults), the absence of this mineral can have negative health consequences (National Institutes of Health). Your body uses selenium for a number of health-promoting functions, such as protecting cells against oxidative stress and helping to maintain both a healthy immune system and thyroid function.
It is well-known that free-radical damage caused by oxidative stress can contribute to a variety of chronic health conditions, like heart disease and cancer. What are free radicals, you ask? Simply put, they are molecules that cause damage to cells. As a powerful antioxidant, selenium helps protect cells from this damage by reducing oxidative stress in the body (Am Heart J, 2008). In fact, a review article of 16 well-controlled studies evaluating 433,000 people with heart disease found that taking selenium supplements decreased levels of the inflammatory marker C-reactive protein (CRP) (J Trace Elem Med Biol, 2017). This indicates that selenium may help lower the risk of heart disease by reducing inflammation and oxidative stress, and it may also help protect the body from other diseases.
As a cornerstone of your body’s antioxidant defense system, selenium also contributes to keeping your immune system strong and resilient. This is important because the immune system helps the body fight off potential threats, like viruses, bacteria and parasites. So, how does selenium do this? Its antioxidant nature helps decrease oxidative stress in the body and, in turn, helps reduce inflammation and enhance immunity. Studies have shown that increased levels of selenium in the blood are associated with an enhanced immune response, while a deficiency of the mineral can contribute to a slower immune response and can harm immune cell function (Mol Nutr Food Res, 2008). Thus, selenium plays a vital role in keeping your immune system strong and healthy.
Many people don’t know that selenium is also a key component for healthy thyroid function. The tissue in the thyroid gland contains more selenium than any other organ in the body, which makes selenium essential for the production of thyroid hormones. Maintaining healthy thyroid function is critical for regulating your metabolism, which affects your energy and bodily functions, immune system regulation, and growth and development. In fact, research suggests that a selenium deficiency has been associated with thyroid conditions like Hashimoto’s thyroiditis, hypothyroidism and others (Institute for Quality and Efficiency in Health Care, 2018; The Journal of Clinical Endocrinology & Metabolism, 2015).
As an antioxidant, a key player in immune health and a critical contributor to thyroid function, among its other roles in the body, selenium is an essential nutrient that every person — male and female, young and old — needs in their diet. Eating selenium-rich foods and potentially supplementing with the mineral are important for your overall health and well-being.