Selenium is an essential mineral, meaning it must be obtained through your diet.It’s only needed in small amounts but plays a major role in important processes in your body, including your metabolism and thyroid function.
What is selenium?
Your body relies on selenium, an important mineral, for many of its basic functions, from reproduction to fighting infection. The amount of selenium in different foods depends on the amount of selenium in the soil where the food was grown. Rain, evaporation, pesticides, and pH levels can all affect selenium levels in soil.
That makes selenium deficiency more common in certain parts of the world. Regardless of where you live, certain factors can make it harder for your body to absorb selenium. For example, you may have difficulty absorbing selenium if you:
▪️ are receiving dialysis.
▪️ are living with HIV.
▪️ have a gastrointestinal condition, such as Crohn’s disease. In addition, those with Graves’ disease or hypothyroidism need to pay special attention to their selenium intake as it serves a protective role for the thyroid.
Selenium is a trace element, or nutrient, that humans need to stay healthy.
It plays a role in many bodily processes, including:
▪️ the function of the thyroid gland.
▪️ production of DNA.
▪️ protecting the body from free radicals, which are unstable cells that move around the body and can increase the risk of diseases, including cancer.
▪️ protecting the body from infection.
Health Benefits Of Selenium .
1. Acts as a powerful antioxidant.
Antioxidants are compounds in foods that prevent cell damage caused by free radicals.
Free radicals are normal byproducts of processes like metabolism that are formed in your body daily.
They often get a bad rap, but free radicals are essential for your health. They perform important functions, including protecting your body from disease.
However, things like smoking, alcohol use, and stress can cause an excess of free radicals. This leads to oxidative stress, which damages healthy cells .
Oxidative stress has been linked to chronic conditions like heart disease, Alzheimer’s, and cancer, as well as premature aging and the risk of stroke .
Antioxidants like selenium help reduce oxidative stress by keeping free radical numbers in check .They work by neutralizing excess free radicals and protecting cells from damage caused by oxidative stress.
2. May reduce your risk of certain cancers.
In addition to decreasing oxidative stress, selenium may help lower the risk of certain cancers.This has been attributed to selenium’s ability to reduce DNA damage and oxidative stress, boost your immune system, and destroy cancer cells .
A review of 69 studies that included over 350,000 people found that having a high blood level of selenium was associated with a lower risk of certain types of cancer, including breast, lung, colon, and prostate cancers .
It’s important to note that this effect was only associated with selenium obtained through foods, not supplements.
However, some research suggests that supplementing with selenium may reduce side effects in people undergoing radiation therapy.
For example, one study found that oral selenium supplements improved overall quality of life and reduced radiation-induced diarrhea in women with cervical and uterine cancer.
3. May protect against heart disease.
A diet rich in selenium may help keep your heart healthy, as low selenium levels have been linked to an increased risk of heart disease.
In an analysis of 25 observational studies, a 50% increase in blood selenium levels was associated with a 24% reduction in the risk of heart disease .Selenium may also lower markers of inflammation in your body — one of the main risk factors for heart disease.
For example, a review of 16 controlled studies including over 433,000 people with heart disease showed that taking selenium supplements decreased levels of the inflammatory marker C-reactive protein (CRP).Additionally, it increased levels of glutathione peroxidase, a powerful antioxidant.
This indicates that selenium may help lower heart disease risk by reducing inflammation and oxidative stress in your body. Oxidative stress and inflammation have been linked to atherosclerosis, or the buildup of plaque in arteries.
Atherosclerosis can lead to dangerous health problems like strokes, heart attacks, and heart disease .
Incorporating selenium-rich foods into your diet is a great way to keep levels of oxidative stress and inflammation to a minimum.
4. Helps prevent mental decline.
Alzheimer’s disease is a devastating condition that causes memory loss and negatively affects thinking and behavior. It’s the sixth-leading cause of death in the United States.
The number of people with Alzheimer’s disease is growing. Thus, finding ways to prevent this degenerative disease is imperative.
Oxidative stress is believed to be involved in both the onset and progression of neurological diseases like Parkinson’s, multiple sclerosis, and Alzheimer’s .
Several studies have shown that patients with Alzheimer’s disease have lower blood levels of selenium .Additionally, some studies have found that antioxidants in both foods and supplements may improve memory in patients with Alzheimer’s.
One small study found that supplementing with one selenium-rich Brazil nut per day improved verbal fluency and other mental functions in patients with mild cognitive impairment .
What’s more, the Mediterranean diet, which is rich in high-selenium foods like seafood and nuts, has been associated with a lower risk of developing Alzheimer’s disease.
5. Is important for thyroid health.
Selenium is important for the proper functioning of your thyroid gland. In fact, thyroid tissue contains a higher amount of selenium than any other organ in the human body .This powerful mineral helps protect the thyroid against oxidative damage and plays an essential role in the production of thyroid hormones.
A healthy thyroid gland is important, as it regulates your metabolism and controls growth and development .
Selenium deficiency has been associated with thyroid conditions like Hashimoto’s thyroiditis, a type of hypothyroidism in which the immune system attacks the thyroid gland.
An observational study including over 6,000 people found that low serum levels of selenium were associated with an increased risk of autoimmune thyroiditis and hypothyroidism .
Additionally, some studies have shown that selenium supplements may benefit people with Hashimoto’s disease.
One review concluded that taking selenium supplements daily for three months resulted in lower thyroid antibodies. It also led to improvements in mood and general well-being in those with Hashimoto’s disease .
However, more research is needed before selenium supplements can be recommended for those with Hashimoto’s disease.
6. Boosts your immune system.
Your immune system keeps your body healthy by identifying and fighting off potential threats. These include bacteria, viruses, and parasites.
Selenium plays an important role in the health of your immune system. This antioxidant helps lower oxidative stress in your body, which reduces inflammation and enhances immunity.
Studies have demonstrated that increased blood levels of selenium are associated with enhanced immune response.
On the other hand, deficiency has been shown to harm immune cell function and may lead to a slower immune response .
Studies have also associated deficiency with an increased risk of death and disease progression in people with HIV, while supplements have been shown to lead to fewer hospitalizations and an improvement in symptoms for these patients .
Additionally, selenium supplements may help strengthen the immune system in people with influenza, tuberculosis, and hepatitis C.
7. May help reduce asthma symptoms.
Asthma is a chronic disease that affects the airways that carry air in and out of the lungs.
These airways become inflamed and begin to narrow, causing symptoms like wheezing, shortness of breath, chest tightness, and coughing .
Asthma has been associated with increased levels of oxidative stress and inflammation in the body .
Due to selenium’s ability to reduce inflammation, some studies suggest that this mineral may help reduce asthma-related symptoms.Research suggests that people who have asthma have lower blood levels of selenium.
In fact, one study showed that asthmatic patients with higher levels of blood selenium had better lung function than those with lower levels .
Selenium supplements may also help reduce asthma-related symptoms.
For example, one study found that giving people with asthma 200 mcg of selenium per day reduced their use of the corticosteroid medications used to control their symptoms .
However, research in this area is conflicting, and larger studies are needed to fully understand selenium’s role in the development and treatment of asthma.
14 Foods That Contain Selenium .
Many foods contain selenium, including :
1. Brazil nuts.
Brazil nuts are very high in selenium, with 1 ounce (oz), or 6–8 nuts, containing 544 mcg. That’s 989% of an adult’s recommended daily value (DV).
Around 3 oz of cooked, yellowfin tuna contains 92 mcg of selenium, or 167% of the adult DV.
The same size portion of halibut has 47 mcg, or 85% of the adult DV.
Once drained, a 3 oz can of sardines in oil, with bones, will account for 82% of the adult DV. That’s because it contains 45 mcg of selenium.
Around 3 oz of canned shrimp has 40 mcg of selenium, or 73% of the adult DV.
6. Enriched macaroni.
Some brands of macaroni are enriched with selenium. Once cooked, one cup of this type of pasta will contain 37 mcg, or 67% of the adult DV.
A 3 oz portion of boneless, roasted turkey contains 56% of the adult DV, which is 31 mcg.
8. Beef liver.
Pan fried, 3 oz of beef liver can provide 28 mcg, or 51% of an adult’s DV.
The light meat in chicken contains the selenium. People should aim for around 3 oz of roasted chicken to consume 22 mcg, or 40% of the adult DV.
10. Cottage cheese.
One cup of 1% milk fat cottage cheese contains 20 mcg, or 36% of the adult DV.
11. Brown rice.
Around one cup of cooked, brown, long-grain rice contains 35% of the adult DV, or 19 mcg.
Eggs are also a good source of selenium. One large, hard-boiled egg will provide 15 mcg of the nutrient. That equates to 27% of the adult DV.
Bread can boost selenium levels, particularly if a person opts for brown varieties. On average, a slice of whole-wheat bread contains 24% of the adult DV, or 13 mcg.
14. Baked beans.
Baked beans are a good source of selenium as well as protein. One cup will provide an adult with 24% of their DV, or 13 mcg.
Jillian Kubala (20-8-2019), “7 Science-Based Health Benefits of Selenium”، www.healthline.com
Natalie Olsen (16-1-2018), “20 Foods Rich in Selenium”، www.healthline.com
15 foods high in selenium/https://www.medicalnewstoday.com/articles/foods-with-selenium