Even though selenium isn’t a famous mineral, it has an essential role in day-to-day body functions. Metabolism and thyroid function are the main processes that affect selenium intake. Due to its integral part in bodily functions, you need to consume it through your diet regularly.
Benefits for Health
Selenium has multiple benefits for health, and the majority of these are backed up by science. It is a mineral you can find in soil and water but you can also find in certain types of foods. Here are the main benefits of selenium:
Antioxidants protect cells from free radicals, which are released in the body through simple processes such as a metabolic breakdown. However, drinking alcohol and smoking regularly produce many free radicals in the body that damage healthy cells. This oxidative stress leads to heart disease, Alzheimer’s, and cancer. 
Selenium and other antioxidants keep free radicals in check and neutralize them to protect healthy cells from damage.
Retains Mental Stability
Alzheimer’s is the sixth-leading cause of death in the USA that causes memory loss while having a negative impact on thinking and behavior. Oxidative stress is a known cause of the onset and progression of Alzheimer’s in people. Studies show that Alzheimer’s patients have low levels of it in their bodies.
Patients with Alzheimer’s showed memory improvement when given antioxidant supplements and foods.
The thyroid tissue contains the highest amounts of it than any other organ in the body; hence it’s an essential nutrient for thyroid function. It protects the thyroid gland from damage through oxidative stress and maintains the production of thyroid hormones.
Hashimoto’s thyroiditis is one of the diseases you can associate with selenium deficiency. In this condition, the immune system starts attacking the thyroid gland, but studies show that patients suffering from this disease showed improvement when given selenium supplements. Another study revealed that lower selenium levels in the body also lead to autoimmune thyroiditis and hypothyroidism.
Boosts the Immune System
The immune system fights off any harmful virus, bacteria, or parasite in the body. It is an antioxidant that lowers oxidative stress and reduces inflammation while boosting immunity.
Reduces the Risk of Cancer
It also reduces oxidative stress, inhibits DNA damage, and destroys cancer cells. Sixty-nine studies show that people with higher selenium blood levels had fewer chances of getting lung, prostate, breast, and colon cancers. However, this effect was due to it obtained through food, not supplements. 
Benefits for Men
It may also help those men who face issues such as subfertility. A trial showed that increasing selenium levels in subfertile men improved sperm motility and increased chances of conception. However, the positivity rate of this trial was 56%; hence more research is a need in this field.
Moreover, it reduces the inflammation necessary for testosterone production and sperm maturation in men.
Benefits for Women
It is an essential mineral that boosts the immune system and acts as a powerful antioxidant, keeping the body free from radical damage. Certain studies suggest it prevents HIV from progressing into AIDS. Some cases show that it may prevent miscarriages from occurring. 
Some researchers say low selenium blood levels during pregnancy may cause childhood asthma development. However, the research is not enough to conclude this with certainty.
Benefits for Skin
Since it is a perfect antioxidant, it also benefits the skin. By fighting free radicals, keeps skin damage at bay, reduces inflammation, and may even lower the risk of skin cancer. Inflammatory cytokines are present in the skin, especially after exposure to UV rays. it also fights these cytokines to prevent skin damage.
Moreover, studies have shown that it lowers pigmentation in the skin. It is also beneficial for the hair since it reduces dandruff and improves skin elasticity.
Benefits for Thyroid
A healthy thyroid is important for metabolism, growth, and development. A selenium deficiency can lead to Hashimoto’s thyroiditis, where the immune system starts attacking the gland. Many studies suggest that incorporating it as a part of your daily diet could reduce the chances of thyroid disorders. This is most effective for women who have thyroid issues. 
More research needs to be conducted to show its effectiveness of it in preventing thyroid disorders.
Despite being a mineral, consuming large amounts of selenium could be dangerous. A high intake of the mineral is, in fact, toxic and fatal for a person. Even though selenium toxicity is rare. It’s suggested to stay within the range of 55 mcg and 400 mcg per day and never exceed the upper limit. 
Brazil nuts contain a high amount of selenium; hence it is suggested to control your intake. Cases of selenium toxicity usually arise due to supplements rather than food. Selenium toxicity leads to hair loss, nausea, dizziness, vomiting, tremors, muscle soreness, and facial flushing. In severe cases, it could also fatally affect the heart and kidneys.
Benefits in Fertility
Even though there is little research in this area, certain studies show that selenium could benefit fertility in both men and women. In men, it is shown to increase sperm motility and help testosterone production. Some studies show that using selenium decreases women’s chances of a miscarriage.
However, for conclusive results, further medical research needs to be conducted.
How to Use Selenium
Selenium is obtained from diet and supplements, but you should stay within the daily recommended range of 55mcg to 400mcg to avoid selenium toxicity. Oysters, brazil nuts, halibut, eggs, sardines, sunflower seeds, chicken breast, and shiitake mushrooms are excellent natural sources of selenium.
You can find selenium supplements from any drug store close to you but make sure you read directions before usage.
Selenium has multiple health benefits for men and women, but relying solely on this mineral is not advised. Moreover, if you use selenium, be careful of the dosage as an excess could cause selenium toxicity. You should add selenium-rich foods to your diet rather than depending on supplements.
Disclaimer: This article is only a guide. It does not substitute the advice given by your own healthcare professional. Before making any health-related decision, consult your healthcare professional.
Editorial References And Fact-Checking
- Elahi, M. M., Kong, Y. X., & Matata, B. M. (2009). Oxidative stress as a mediator of cardiovascular disease. Oxidative medicine and cellular longevity, 2(5), 259–269. https://doi.org/10.4161/oxim.2.5.9441
- Cai, X., Wang, C., Yu, W., Fan, W., Wang, S., Shen, N., Wu, P., Li, X., & Wang, F. (2016). Selenium Exposure and Cancer Risk: an Updated Meta-analysis and Meta-regression. Scientific reports, 6, 19213. https://doi.org/10.1038/srep19213
- Rayman M. P. (2000). The importance of selenium to human health. Lancet (London, England), 356(9225), 233–241. https://doi.org/10.1016/S0140-6736(00)02490-9
- Office of Dietary Supplements – Selenium. (n.d.). Retrieved September 16, 2022, from https://ods.od.nih.gov/factsheets/Selenium-HealthProfessional/