Selenium is a mineral with antioxidant, anti-inflammatory and cardioprotective properties, which strengthens the immune system, in addition to helping to prevent diseases such as multiple sclerosis, heart attack and stroke.
Selenium is naturally found in soil and water, but it is also present in various foods, such as Brazil nuts, beans, wheat flour and eggs, for example. See a complete list of foods rich in selenium.
Additionally, selenium is also found in the form of supplements. However, this supplement should only be used under the guidance of a doctor or nutritionist, as excess selenium can cause hair loss, tiredness and thyroid changes.
What is selenium used for?
The main health benefits of selenium are:
1. Prevent premature aging
Because it has antioxidant action, selenium fights free radicals in the body, protecting healthy skin cells and thus preventing wrinkles, sagging and premature aging. Discover other foods with antioxidant action.
2. Avoid neurodegenerative diseases
By acting as an antioxidant and protecting the cells of the nervous system against damage caused by free radicals, selenium helps prevent neurodegenerative diseases such as Alzheimer’s, Parkinson’s and multiple sclerosis.
This benefit is even greater when selenium is consumed from foods that are sources of healthy fats, such as Brazil nuts, egg yolks and chicken, for example.
3. Help prevent cancer
Selenium regulates and protects cells against changes in their DNA that can cause the formation of tumors. Thus, selenium can help prevent the emergence of some types of cancer, such as lung, breast, prostate and colon.
4. Maintain thyroid health
Selenium is found in large quantities in the thyroid, helping to maintain the health of this gland. This is because this mineral is essential for converting thyroid hormones T4 into T3, regulating their concentration in the body.
Selenium deficiency can cause problems such as Graves’ disease or Hashimoto’s thyroiditis, conditions where the body’s defense cells attack the thyroid, causing hyperthyroidism or hypothyroidism.
5. Prevent cardiovascular diseases
Selenium reduces inflammation and increases the amount of glutathione in the body, an enzyme with powerful antioxidant action. Thus, selenium reduces the oxidation of “bad” cholesterol, LDL, in blood vessels, reducing the risk of cardiovascular diseases, such as atherosclerosis, heart attack, stroke and thrombosis.
6. Strengthen the immune system
Adequate amounts of selenium in the body help strengthen the immune system, because this mineral protects and improves the functions of immune system cells.
7. Help with weight loss
Because it is necessary for the proper functioning of the thyroid, selenium helps with weight loss. This is because this mineral helps prevent hypothyroidism, a change in the thyroid that slows down metabolism, favoring weight gain.
Foods rich in selenium
Some foods rich in selenium include those of animal origin, such as beef, fish and eggs. Furthermore, selenium is also found in excellent quantities in foods of plant origin, such as black beans, Brazil nuts and sunflower seeds. See a complete list of foods rich in selenium.
Recommended daily amount
The recommended amount of selenium varies according to age and stage of life, as shown in the following table:
A varied and healthy diet naturally guarantees the recommended amounts of selenium. Consuming 1 Brazil nut per day, for example, meets the daily selenium recommendations.
When to take selenium supplement
The use of supplements may be indicated in conditions that increase the daily requirement or decrease the absorption of selenium, such as Crohn’s disease, HIV, dialysis, or receiving food through a vein.
Selenium supplements are sold in capsules or tablets and can contain from 50 to 200 mcg. The recommended dosage of this supplement varies according to the degree of selenium deficiency and the objective being treated. Therefore, selenium supplement should only be used under the guidance of a doctor or nutritionist.
Selenium deficiency
Selenium deficiency can arise in situations with greater need or difficulty in absorbing this mineral, such as people with Crohn’s disease, HIV or on dialysis, for example.
Selenium deficiency can cause physical and mental fatigue, hair loss, hypothyroidism or heart problems.
Furthermore, a low amount of this mineral in the body can also cause Kashin-Beck disease, a type of osteoarthritis, or Keshan disease, a disease that causes heart failure.
Excess selenium
Excess selenium in the body can occur with the consumption of large quantities of foods rich in this mineral, especially Brazil nuts. Furthermore, taking high doses of selenium supplements can also cause excess selenium in the body.
Consuming 1.3 mg or more of selenium per day can cause simple symptoms such as loss of nails and hair, garlic aroma, stomach pain, nausea, vomiting, diarrhea, tiredness or irritability.
However, excess selenium can also cause more serious symptoms such as shortness of breath, thyroid changes, heart attack or kidney failure.
