Selenium is an essential trace mineral. Your body only needs it in small amounts.This means your body must get this mineral in the food you eat. Small amounts of selenium are good for your health. Selenium is incorporated in a small cluster of important proteins, each of which plays a critical role in our health.
Selenium helps your body with:
- It works as an antioxidant, especially when combined with vitamin E. Antioxidants like selenium help fight damaging particles in the body known as free radicals. Free radicals can damage cell membranes and DNA, and may contribute to aging and health conditions, including heart disease and cancer.
- Protecting you after a vaccination
- Making special proteins, called antioxidant enzymes. These play a role in preventing cell damage
- Prevent cardiovascular disease
- Protect the body from the poisonous effects of heavy metals and other harmful substances
- Selenium plays a role in thyroid function. Studies suggest that people (especially women) who have low blood levels of selenium (and iodine) might develop problems with their thyroid.
- Your immune system also needs selenium to work properly.
If you are healthy and eat a well-balanced diet, you probably get enough selenium. You may have low levels of selenium if you:
- Smoke cigarettes
- Drink alcohol
- Take birth control pills
- Have a condition that prevents your body from absorbing enough selenium, such as Crohn disease or ulcerative colitis
Selenium deficiency is very rare. It may cause some type of heart disease and a male infertility.
Some studies suggest that people with lower blood selenium levels are more likely to have poorer cognitive and mental function.
People should get most of their nutrients from food. Food is the best source of vitamins, minerals and other substances that are beneficial for your total health.
Selenium is found naturally in many foods. The amount of selenium in plant foods depends on the amount of selenium in the soil where they were grown.
Food sources of selenium are
- Brasil nuts
- sea food (oysters, tuna, salmon)
- mushrooms (especially shiitake)
- eggs (cooked)
- soy yogurt
Selenium dietary supplements
Recommended source of selenium is food, but if you have a condition that requires controlled intake amount of selenium, be aware of the upper limits of daily intake, recommended by US department of Health and Human services, Office of dietary supplements, listed in the next table:
|Birth to 6 months||45 mcg|
|Infants 7-12 months||60 mcg|
|Children 1-3 years||90 mcg|
|Children 4-8 years||150 mcg|
|Children 9-13 years||280 mcg|
|Teens 14-18 years||400 mcg|
Can selenium be harmful?
Yes, if you intake too much. Brazil nuts contain very high amounts of selenium (68-91 mcg per nut) and can cause you to go over the upper limit if you eat too many. Getting too much selenium over time can cause the following:
- Garlic breath
- Skin rashes
- Metallic taste in the mouth
- Brittle hair or nails
- Loss of hair or nails
- Discolored teeth
- Nervous system problems
Before deciding to take dietary supplements talk to your healthcare provider, if any of them may interfere with your regular therapy, and what dose fits you.