What Are The Dangers Of Selenium In Food?

Your body needs a small amount of selenium each day, but like any mineral or vitamin, you can experience adverse side effects if you consume too much. The selenium in your food comes from plants and animal products, and the higher the selenium content in the soil, the higher the selenium concentration in the food. The Office of Dietary Supplements indicates that residents of North and South Dakota and Nebraska consume the most selenium, because of the naturally high selenium concentrations in the soil.

Selenium Information

Selenium plays a role in your thyroid regulation and immune system function. Because the thyoid gland needs selenium to circulate thyroid hormones in the bloodstream, inadequate selenium intake can affect your metabolism and growth, according to the Linus Pauling Institute. Selenium affects how well your immune system functions through its ability to help the development of your body's white blood cells. White blood cells work together to fight infections within your body. Selenium also functions as an “antioxidant enzyme,” which helps your body fix the damage to your cells caused by free radicals.

Maximum Intake

The minimum recommended dosage of selenium is 55 micrograms per day for adults, and 60 micrograms per day for pregnant women. The maximum amount of selenium you should consume should be 400 micrograms, according to a fact sheet from the Office of Dietary Supplements. While most foods have a relatively low concentration of selenium, the exception to this is Brazil nuts from farms with selenium-rich soil. A 1-ounce serving of the nuts, which the Linus Pauling Institutes explains is equal to only six kernels, has 544 micrograms of selenium, or 136 percent more than the maximum recommended intake.

Side Effects

An overabundance of selenium intake can cause selenois, which the ODS explains is a disorder that may cause your hair to thin or fall out, produce white spots on your nail bed, give you bad breath and make you feel tired and irritable. A review article published in the August 1997 edition of "The American Journal of Clinical Nutrition" indicates that a manufacturing error in a dietary supplement that contained 182 times more selenium than the label indicated caused serious adverse effects to humans, including nervous system damage and problems with the skin and teeth.

Foods High in Selenium

In addition to Brazil nuts, other foods high in selenium include tuna fish canned in oil and beef. The tuna has 63 micrograms of selenium per 3 ounces, and beef has 35 micrograms in 3.5 ounces, according to the ODS. Cod, turkey and chuck roast have between 23 and 32 micrograms per 3 to 3.5 ounce serving. Oatmeal contains 12 micrograms of selenium in 1 cup of cooked oats, a cinnamon-raisin bagel has 22 micrograms and a slice of whole-wheat bread has 10 micrograms. A bowl of cream of wheat has over 30 micrograms of selenium, according to the U.S. Department of Agriculture. When eating foods you know contain large amounts of selenium, avoid taking a dietary supplement that has more than the recommended daily value of the mineral to help prevent selenosis.