Nutritional roles and risks of selenium deficiency

Selenium is a vital mineral required in small amounts for essential bodily functions, including thyroid hormone metabolism, DNA synthesis, and protection against oxidative stress. It is a key component of selenoproteins, which support various physiological processes.

According to the National Institutes of Health (NIH), research does not provide a definitive answer regarding the benefits of selenium supplements for thyroid diseases, and a thyroid diagnosis alone is not a reason to self-prescribe supplements. Excessive intake through supplements can also be harmful.

Groups at higher risk for deficiency include individuals undergoing kidney dialysis, people living with HIV, and populations whose diets rely heavily on plant foods grown in selenium-poor soil. Some European populations, particularly those following vegan diets, have also shown lower intake levels. Symptoms of low selenium levels can include fatigue, muscle weakness, and difficulty concentrating, though these symptoms are non-specific.