Selenium is sort of like one of the body’s specialized workers. It doesn’t have quite as many jobs as other nutrients, but the jobs it does have are absolutely vital to our health. Without Selenium working to keep its areas of effect in check we would quickly become quite unhealthy.

What Is It?

Selenium is a mineral [1] that occurs naturally in water, and in the soils we use to grow our food. The selenium makes its way from the soil into the plants we consume and into our drinking water. For the purposes of human health, Selenium is considered a trace mineral.

Trace minerals are those that the body requires for proper functioning, but only in small amount. Make no mistake, though, the small amount required by the body does not mean Selenium isn’t vital to our health.

What Is Its Biological Role?

One of Selenium’s jobs is shared by many other nutrients we consume: it is a powerful antioxidant. Antioxidants are compounds in our body that work to repair damage caused by harmful compounds that we collectively refer to as free radicals.

As such, it can slow the signs of aging by helping to repair cells as they are damaged, and promote a healthy level of new cell generation. Antioxidants also can sometimes fight against cancers. Research has shown that increasing selenium intake can strengthen the body’s immune system and stave off common forms of cancer.

It also helps reduce blood pressure and promote cardiovascular health by reducing inflammation inside the body. Selenium is also responsible for the creation of special proteins that perform a variety of functions that range from protecting and regulating the thyroid gland to lessening the severity of asthma problems and increasing sperm motility.

How Does It Help Bodybuilders and People Who Work Out?

Make no mistake, selenium is vital to a health body across the board. However, whether or not you need to increase your selenium intake depends very little on lifestyle factors other than diet.

Most fitness enthusiasts already eat well, and so typically do not need to worry about getting enough selenium in their diet. This particular mineral is one you do not want to supplement if you do not need extra amounts; the negative effects of too much selenium in the body can be just as much of a health concern as too little selenium in the body.

Therefore, the best advice regarding selenium for fitness enthusiasts is simply to ensure you eat a wholesome, varied diet to keep selenium levels consistent.

What Foods Contain It?

Because of the way selenium is absorbed by the body, the National Institute of Health recommends that every effort is made to get your daily dose of selenium almost exclusively from dietary sources.

The top ten selenium-rich foods are, in order:

  • brazil nuts,
  • eggs,
  • sunflower seeds,
  • lamb or beef liver,
  • rockfish,
  • tuna,
  • herring,
  • chicken,
  • salmon,
  • turkey,
  • and chia seeds.

How Much Of It Do You Need?

At birth, the recommended daily allowance of selenium [2] is 20mcg per day. This amount rises slightly every few years until we reach puberty. Anyone aged 14 and older is recommended to consume 55mcg per day. Women who are pregnant should have 60mcg per day, and women who are breastfeeding should have 70mcg per day.

Are There Risks Associated With Consuming Too Much Of It?

Selenium poisoning is very rare. Typically, it is only seen in individuals who are taking selenium supplements in doses far higher than what they need, and without consulting with their primary doctors beforehand.

Supplementing with selenium to the point of toxicity can cause bad breath, nausea, fever, and complications to your liver, kidney, and heart health. Extreme toxicity can cause heart attacks and respiratory distress.

Are There Risks Associated With Consuming Too Little Of It?

Selenium deficiency [3] can sometimes be a concern based on where your food is grown. Selenium is only present in foods we eat because of the environment where they are grown.

Foods grown in certain parts of the country or the world will have different levels of selenium even though they are the same type of food, purely because of the nutrient content of that area’s soil. For example, American populations in the Pacific Northwest who get most of their food from local sources have some of the lowest selenium levels in the country because the soil there has very little selenium.

Deficiencies can cause weakened immune systems resulting in greater frequency of illnesses, cognitive decline which can show itself in decreased alertness or confusion, and a generally higher rate of mortality.

Final Take

Hopefully now you know a bit more about selenium, a trace mineral with a big impact. Common enough in foods that we can usually get the small amount we need from our diets, this specialized mineral helps us to stay healthy and feel our best even in the face of potentially damaging concerns such as free radicals, cancer, and attacks to our immune system.


[1] MedlinePlus. Selenium in Diet., 2015.

[2] Office of Dietary Supplements, National Institute of Health. Selenium-Consumer Fact Sheet. US Department of Health and Human Services, 2016.

[3] Wikipedia. Selenium Deficiency., 2016.