Selenium is one of many important dietary minerals, and we require a small amount of selenium in our daily diet. Selenium is incorporated in a small cluster of important proteins, each of which plays a critical role in our health. Scientists named these selenium-containing proteins "selenoproteins."
Selenium has received publicity over the past couple decades based on some confusing and contradictory research about whether low-selenium diets are implicated in cancer risk. To date, this is still a question without a clear answer. Regardless of whether selenium deficiency is associated with increased risk of cancer, it is clear that good selenium nutrition is important for good antioxidant protection, among other things.
Luckily, American soils—and therefore, American diets—are rich in selenium. In fact, there are very few areas in the world where selenium deficiency is seen, and these areas are generally marked by calorie malnutrition, as well.
Role in Health Support
Antioxidant Protection
Selenium is required for the proper activity of a group of enzymes collectively called glutathione peroxidase. These enzymes each help turn toxic hydrogen peroxide into harmless water. Of the eight known glutathione peroxidase enzymes, five of them require selenium.
In addition to the activity of glutathione peroxidase, selenium-containing enzymes are involved in recycling of vitamin C from its spent form back to its active one, allowing for greater antioxidant protection.
This is not just a research world issue. In parts of the world where diets are low in selenium, health problems routinely occur due to poor antioxidant protection. Animal studies suggest that as little as two weeks without dietary selenium sources can lead to disruptions in protection against free radicals.
Support Normal Thyroid Function
A selenium-containing enzyme is responsible for transforming a less active thyroid hormone called T4 into the more active T3. As you'll see below in the Relationship with Other Nutrients section, selenium and iodine work together to keep thyroid function strong and consistent.
Like the antioxidant protection issue, this is not just an esoteric concern. Researchers have been able to induce problems with the thyroid gland in just two months of a low-selenium diet.
Summary of Food Sources
Probably, if you've read about food sources of selenium, you've read about Brazil nuts as a strong source of the mineral. Depending on where they are grown, this is likely to be true—one ounce of Brazil nuts may contain as much as 10 times the Recommended Daily Allowance (RDA) recommendation for selenium intake.
Whole grains and seeds are well represented in the good selenium sources category. With these foods, and plant foods in general, the amounts of selenium per serving are much more variable, and will be dependent on the selenium content of the soil in which they are grown. The upper Midwest, coastal California, and the Middle Atlantic States tend to have some of the strongest selenium content in the United States.
1. Fights Prostate Cancer
Low level of selenium in the body may increase the risk of prostate cancer. It is known that selenium can enhance the antioxidant capacity of the body, and it may help to reduce cell damage that is associated with prostate cancer. Those who are affected by selenium deficiency can become less vulnerable to prostate cancer if they increase their intake of selenium.
2. Prevents Keshan Disease
Keshan disease is a fatal condition that is characterized by inflammation of heart muscles, and the problem is mostly found in areas in China where the soil has low levels of selenium. Those who suffer from this disease will become more susceptible to heart disease, cancer, high blood pressure and strokes. Since selenium assists in the functioning of the thyroid gland and it offers protection against heart conditions, taking selenium supplements can help prevent the disease.
3. Reduces Mal-Absorption
Mal-absorption refers to abnormal absorption of nutrients in the gastrointestinal tract. It is found mostly in children who suffer from selenium deficiency.
4. Lowers Risk of Cardiomyopathy
Cardiomyopathy is another disease that causes the muscles of the heart to deteriorate. Low levels of selenium result in the lack of antioxidants in the heart and the muscles, and it's one of the factors that contribute to the development of cardiomyopathy.
5. Cures Intracranial Pressure Symptoms
Intracranial pressure symptoms include headache, speech disorder, nausea, vertigo and fatigue. According to research, these symptoms can be treated by increasing intake of selenium.
6. Treats Asthma
It's been found that people who suffer from asthma don't have sufficient amounts of selenium in their bodies. Selenium as well as beta carotene, vitamin C and vitamin E are antioxidants that can prevent and control asthma attacks.
7. Helps to Eliminate Dandruff
Selenium is beneficial to the hair and scalp. As such, shampoos that contain selenium are effective in treating dandruff problems.
Selenium can be found in foods such as mangos, mushrooms, sunflower seeds, garlic, walnuts, raisins, oatmeal, chia seeds, onions, and radishes.
Selenium has received publicity over the past couple decades based on some confusing and contradictory research about whether low-selenium diets are implicated in cancer risk. To date, this is still a question without a clear answer. Regardless of whether selenium deficiency is associated with increased risk of cancer, it is clear that good selenium nutrition is important for good antioxidant protection, among other things.
Luckily, American soils—and therefore, American diets—are rich in selenium. In fact, there are very few areas in the world where selenium deficiency is seen, and these areas are generally marked by calorie malnutrition, as well.
Role in Health Support
Antioxidant Protection
Selenium is required for the proper activity of a group of enzymes collectively called glutathione peroxidase. These enzymes each help turn toxic hydrogen peroxide into harmless water. Of the eight known glutathione peroxidase enzymes, five of them require selenium.
In addition to the activity of glutathione peroxidase, selenium-containing enzymes are involved in recycling of vitamin C from its spent form back to its active one, allowing for greater antioxidant protection.
This is not just a research world issue. In parts of the world where diets are low in selenium, health problems routinely occur due to poor antioxidant protection. Animal studies suggest that as little as two weeks without dietary selenium sources can lead to disruptions in protection against free radicals.
Support Normal Thyroid Function
A selenium-containing enzyme is responsible for transforming a less active thyroid hormone called T4 into the more active T3. As you'll see below in the Relationship with Other Nutrients section, selenium and iodine work together to keep thyroid function strong and consistent.
Like the antioxidant protection issue, this is not just an esoteric concern. Researchers have been able to induce problems with the thyroid gland in just two months of a low-selenium diet.
Summary of Food Sources
Probably, if you've read about food sources of selenium, you've read about Brazil nuts as a strong source of the mineral. Depending on where they are grown, this is likely to be true—one ounce of Brazil nuts may contain as much as 10 times the Recommended Daily Allowance (RDA) recommendation for selenium intake.
Whole grains and seeds are well represented in the good selenium sources category. With these foods, and plant foods in general, the amounts of selenium per serving are much more variable, and will be dependent on the selenium content of the soil in which they are grown. The upper Midwest, coastal California, and the Middle Atlantic States tend to have some of the strongest selenium content in the United States.
1. Fights Prostate Cancer
Low level of selenium in the body may increase the risk of prostate cancer. It is known that selenium can enhance the antioxidant capacity of the body, and it may help to reduce cell damage that is associated with prostate cancer. Those who are affected by selenium deficiency can become less vulnerable to prostate cancer if they increase their intake of selenium.
2. Prevents Keshan Disease
Keshan disease is a fatal condition that is characterized by inflammation of heart muscles, and the problem is mostly found in areas in China where the soil has low levels of selenium. Those who suffer from this disease will become more susceptible to heart disease, cancer, high blood pressure and strokes. Since selenium assists in the functioning of the thyroid gland and it offers protection against heart conditions, taking selenium supplements can help prevent the disease.
3. Reduces Mal-Absorption
Mal-absorption refers to abnormal absorption of nutrients in the gastrointestinal tract. It is found mostly in children who suffer from selenium deficiency.
4. Lowers Risk of Cardiomyopathy
Cardiomyopathy is another disease that causes the muscles of the heart to deteriorate. Low levels of selenium result in the lack of antioxidants in the heart and the muscles, and it's one of the factors that contribute to the development of cardiomyopathy.
5. Cures Intracranial Pressure Symptoms
Intracranial pressure symptoms include headache, speech disorder, nausea, vertigo and fatigue. According to research, these symptoms can be treated by increasing intake of selenium.
6. Treats Asthma
It's been found that people who suffer from asthma don't have sufficient amounts of selenium in their bodies. Selenium as well as beta carotene, vitamin C and vitamin E are antioxidants that can prevent and control asthma attacks.
7. Helps to Eliminate Dandruff
Selenium is beneficial to the hair and scalp. As such, shampoos that contain selenium are effective in treating dandruff problems.
Selenium can be found in foods such as mangos, mushrooms, sunflower seeds, garlic, walnuts, raisins, oatmeal, chia seeds, onions, and radishes.