Selenium

Selenium has actually attracted attention because of its antioxidant homes. Antioxidants secure cells from damage. Evidence that selenium supplements may reduce the odds of prostate cancer has actually been mixed, but many research studies recommend there is no real advantage. Selenium does not seem to impact the danger of colorectal or lung cancer. But beware: some studies recommend that selenium might increase the danger of non-melanoma skin cancer.

Amongst healthy people in the U.S., selenium deficiencies are unusual. But some health conditions– such as HIV, Crohn’s disease, and others– are connected with low selenium levels. People who are fed intravenously are likewise at risk for low selenium. Doctors often recommend that people with these conditions use selenium supplements.

Selenium has actually likewise been studied for the treatment of lots of conditions. They range from asthma to arthritis to dandruff to infertility. Nevertheless, the outcomes have actually been inconclusive. [3]

Health Benefits of Selenium

Potentially Reliable:

1) Thyroid Conditions

Selenium is most focused in the thyroid and assists control its function. Serious selenium deficiency may hinder its function and is connected to different thyroid conditions.

Hashimoto’s Illness

Selenium supplementation can be useful for people with Hashimoto’s thyroiditis or autoimmune hypothyroidism. In a review of four clinical research studies, selenium enhanced mood, basic well-being, and thyroid peroxidase antibodies in individuals with Hashimoto’s. The direct benefits on thyroid structure and function were less clear, though.

Grave’s Disease

Tomb’ disease (GD) is an autoimmune illness in which the thyroid becomes enlarged and overactive. In 38 selenium-deficient patients with Tomb’s illness, Se supplements significantly minimized thyroid hormonal agents.

However, it revealed no short-term benefits in another trial of 30 GD clients with regular selenium levels.

The benefits of Se supplements for Graves’ illness might be limited to Se-deficient patients.

Other.

Some pregnant ladies experience mildly minimized thyroid function, also referred to as subclinical hypothyroidism (increased TSH, typical T4).

In an analysis of over 300 pregnant ladies, lower selenium blood levels were connected to thyroid augmentation and damage. Selenium supplements helped restore thyroid health, especially after birth. Selenium was used in the form of Selenomethionine, a naturally-occurring selenium-bound amino acid.

In mice with autoimmune thyroiditis, selenium increased T-reg immune cells, which are crucial for getting rid of the destructive autoimmune action. It also reduced blood levels of disease-related antibodies (thyroglobulin TgAb).

2) Viral Infections

Absence of selenium can set off the body immune system and trigger even safe virus infections to progress and become dangerous. In the most serious cases, this can result in total heart failure (Keshan disease).

Appropriate selenium intake protects immune cells and help in producing antibodies. Lower selenium levels can increase damage (by means of oxidative tension) in healthy cells, lowering immune defense, triggering infections, and triggering their faster department.

HIV infections can trigger selenium deficiency, while supplementation might help fight HIV and improve outcomes. In one trial of 18 HIV-positive individuals, selenium in mix with standard drugs improved the quality of life. Selenium likewise blocked the duplication of the virus in cellular and animal research studies.

Selenium levels might anticipate the illness result in HIV-positive people. In one study, selenium-deficient HIV patients were practically 20 times more likely to die from HIV than those with typical selenium levels.

In one study on children, low selenium levels not only increased the likelihood of dying from HIV but were likewise connected to faster spreading of the disease.

3) Kashin-Beck Illness Prevention

Kashin-Beck illness (KBD) is an endemic disease of the joints and bones, generally happening in specific China areas, particularly Tibet. Selenium shortage plays an essential role, in addition to different environmental and hereditary elements.

According to a meta-analysis of 11 Chinese medical trials with 2652 clients, including Se-enriched salt to a diet plan lowers the chances of Kashin-Beck illness by 84% in healthy children, compared with iodized salt.

Nevertheless, Se supplementation didn’t improve joint discomfort or mobility in 324 children with Kashin-Beck illness. The authors emphasized the function of iodine shortage in KBD.

4) Preeclampsia

Preeclampsia is defined by hypertension, swelling, and the presence of protein in the urine during pregnancy.

In a meta-analysis of 3 trials with 439 pregnant ladies, Se supplements (60-100 mcg daily for up to 6 months) minimized the threat of preeclampsia by 72% compared to placebo. According to 13 observational studies (1,515 participants), pregnant females with low Se levels have a higher threat of preeclampsia.

Insufficient Evidence:

No valid medical proof supports using selenium for any of the conditions in this area. Below is a summary of up-to-date animal research studies, cell-based research, or low-grade medical trials which must trigger more examination. However, you should not interpret them as helpful of any health advantage.

5) Brain Defense

The benefits of fish intake are frequently attributed to polyunsaturated fatty acids, omega-3s, but high quantities of selenium discovered in fish might be equally important. Selenium works in synergy with the fatty acids, preventing their breakdown and enhancing their advantageous results on cognition.

In one research study on 200 older people, fish consumption increased selenium blood levels more than omega-3 levels. According to the authors, much better cognitive function in the elderly may depend straight on selenium [24]

Selenium is really essential for your brain health. Low selenium levels are connected to poor cognition, memory problems, and low neurotransmitter levels in the brain. Alzheimer’s patients had only 60% of the brain selenium levels of healthy individuals in one research study.

6) Cancer Avoidance

The function of selenium in cancer avoidance is a hot topic of argument and the findings are contrasting. Selenium supplements aren’t approved for cancer prevention or treatment.

Supportive Research

Ever since the 70s, research studies have actually been reporting that increased selenium intake minimizes cancer deaths and vice versa. In one study, the dietary intake of selenium in 27 nations was linked to less deaths from cancer. In the United States, deaths from cancer were much greater in low selenium counties, in which individuals are more likely to be deficient.

Early research studies of approximately 11,000 people reported that low selenium status is related to an increased cancer danger of cancer and death. The approximated threat varied from 2 to six-fold and was at times only relevant to men.

Some recent studies support early findings. A little increased selenium intake– still well listed below harmful levels– was connected with a lower risk of colorectal and prostate cancer.

In 37 males, a combination of Milk thistle (Silymarin) and selenium reduced LDL, swelling, and overall cholesterol after prostate removal surgical treatment, possibly preventing prostate cancer regression and progression.

Conflicting Research

A considerable restriction is that a lot of research studies of selenium intake and cancer threat are observational. Observational studies can make associations, however can’t associate any causation.

There have been really couple of scientific trials utilizing selenium as a restorative agent, which are required to determine its impacts. Lots of other aspects– including lifestyle, genes, gender, and age, stage, and type of cancer– will affect cancer outcomes and the preventive action of selenium.

In one clinical trial of over 1,000 people with a history of nonmelanoma skin cancer, 200 µg/ day of selenium (as selenium yeast) didn’t lower the chances of relapse. However it did lower all-type cancer mortality by 50% and cancer rates by 37%. It specifically lowered the rates of prostate, colon, and lung cancer.

According to a meta-analysis of 15 medical trials, Se supplements may decrease the threat of lung cancer in lacking patients but increase the danger in clients with typical Se levels.

Once again, the benefits of Se supplements in fact stemmed from fixing a shortage.

Discouraging Research study

Despite a number of appealing medical trials, the biggest review current concluded that there is no evidence to support increased selenium intake through diet plan or supplements in preventing cancer in humans. This review consisted of 83 research studies and emphasized the above-mentioned downsides of the offered research studies.

Selenium supplementation or increased dietary intake would undoubtedly offer benefits to Se-deficient individuals. However considered that shortage is rather unusual, it would be best to examine selenium blood levels before taking supplements. Whether selenium avoids cancer is still unknown while taking in excessive selenium can only be damaging.

More clinical research study is needed, considering genetics, dietary status, and different kinds of selenium supplements.

7) Immune Response

Selenium shortage impairs immune function. Appropriately, selenium supplements promotes the body immune system, even in individuals who are not lacking. Lymphocytes of individuals who supplemented with selenium (200 µg/ day) were more active and efficient at ruining foreign intruders and growth cells.

Selenium might be more crucial for appropriate immunity than was formerly recognized. Activated immune cells have an increased need for selenium and its amino-acid bound form (selenocysteine), according to current studies.

Helpful For Th2-Dominant People

Selenium supplementation might assist divert the immune response away from the Th2-type and promote the Th1-type, which protects against asthma, allergies, viral infections and cancer.

More research studies are required to evaluate the immune-stimulating homes of selenium.

8) Fertility and Reproductive Health

Well balanced selenium levels are essential for reproductive health in both males and females. In men, selenium is very important for producing sperm and testosterone.

In a study of 69 males with fertility problems, selenium supplements mildly increased sperm motility however didn’t enhance sperm density. 11% of the men who took selenium attained paternity, compared to none in the placebo group.

However, Se supplements had no benefits on sperm count, motility, or quality in a comparable trial of 33 patients.

In research studies on male rats, selenium increased testosterone levels however just in rats who were selenium-deficient.

In women, appropriate selenium levels are specifically important during early pregnancy. In one study, ladies who struggled with frequent miscarriages were most likely to have lower selenium blood levels. Selenium shortage was also linked to an increased possibility of miscarriages in animal research studies.

9) Heart Health

Selenium might protect against cardiovascular disease, probably by enhancing the antioxidant glutathione, minimizing oxidative stress and avoiding platelet clumping.

Selenium shortage ultimately triggers hazardous, reactive substances to develop, making blood vessels less versatile and platelets more “sticky”. For instance, in men with heart problem, low selenium may cause platelets to clump together and narrow capillary, possibly getting worse heart health.

The clinical outcomes are still mixed, though. In one study, low selenium was connected to a 2- to three-fold increase in heart disease, while in another study men with low selenium were at an increased danger of cardiovascular disease or stroke. However other small studies didn’t find any clear link between heart problem threat and selenium levels.

In 668 senior Swedish individuals, supplementation with selenium (200 μg) and coenzyme Q10 (200 mg) for four years substantially minimized the threat of heart failure. It dropped by 50% in formerly Se-deficient patients and by 62% in clients with moderate Se levels.

Patients with high Se levels didn’t gain from supplements, recommending once again that the benefits might be restricted to Se-deficient individuals.

Further research study needs to determine whether selenium supplementation secures against cardiovascular disease and under which occasions.

10) Mood and Stress And Anxiety

Low selenium levels have actually been connected to anxiety, stress and anxiety, tiredness, and mental confusion. In one research study of 50 people, selenium supplements (100 mcg/day) over 5 weeks enhanced state of mind, energy levels, and minimized anxiety.

Selenium supplementation over 8 weeks noticeably enhanced anxiety and mildly lowered anxiety in a study on senior citizens residing in assisted living home.

Selenium Blood Test & Normal Varieties

The margin between selenium deficiency, ideal and above-optimal levels and toxicity is extremely narrow. Knowing your selenium status can be useful in determining prospective health problems.

The most common method to determine selenium status is using blood biomarkers that reflect selenium intake, which can include the following:.

• Elemental selenium (typical variety: 70– 160 ng/mL)
• Glutathione peroxidase
• Selenoprotein P, the main provider of selenium to tissues

To increase durability, battle inflammation, and help in cancer avoidance, even higher blood levels have been looked into. A little above-optimal intake might decrease the threat of lung, prostate and colorectal cancers, however the proof is undetermined.

Aside from blood tests, long-term selenium status can additionally be assessed by measuring selenium concentrations in toe nails and hair. [4]

16 Fascinating Selenium Realities

Selenium is a chemical aspect found in a wide range of items. Here are some intriguing truths about selenium:.

• Selenium gets its name from the Greek word “selene,” which implies “moon.” Selene was the Greek goddess of the moon.
• Selenium has atomic number 34, meaning each atom has 34 protons. The element sign of selenium is Se.
• Selenium was discovered collectively in 1817 by Swedish chemists Jöns Jakob Berzelius (1779– 1848) and Johan Gottlieb Gahn (1745– 1818).
• Although it is unusually discovered, selenium does exist in reasonably pure form, complimentary in nature.
• Selenium is a nonmetal. Like numerous nonmetals, it shows different colors and structures (allotropes) depending upon the conditions.
• Brazil nuts are high in selenium, even if they are grown in soil that is not rich in the element. A single nut supplies enough selenium to meet the everyday requirement for a human grownup.
• English electrical engineer Willoughby Smith (1828– 1891) discovered that selenium responds to light (photoelectric result), leading to its use as a light sensing unit in the 1870s. Scottish-born American innovator Alexander Graham Bell (1847– 1922) made a selenium-based photophone in 1879.
• The primary use of selenium is to decolorize glass, to color glass red, and to make the pigment China Red. Other uses remain in photocells, in printer and copy machines, in steels, and in semiconductors.
• There are six natural isotopes of selenium. One is radioactive, while the other five are stable. However, the half-life of the unsteady isotope is so long that it is basically stable. Another 23 unstable isotopes have been produced.
• Some plants need high levels of selenium to make it through, so the existence of those plants means the soil is abundant in the aspect.
• Liquid selenium shows incredibly high surface area stress.
• Selenium is important to numerous enzymes, consisting of antioxidant enzymes glutathione peroxidase and thioredoxin reductase and the deiodinase enzymes that transform thyroid hormonal agents into other forms.
• Around 2,000 tons of selenium are extracted annually worldwide.
• Selenium is most frequently produced as a by-product of copper refining.
• The element was included in the films “Ghostbusters” and “Evolution.” [5]

Chemical value of selenium

Selenium is an element present in the periodic table of all the existing elements discovered by people. The various chemical and essential residential or commercial properties of selenium are mentioned listed below.

Selenium inhabits the 34th aspect in the table of elements. This likewise indicates that the atomic number of selenium is 34.

Like every other component on the table of elements, selenium has an atomic sign, too, which is ‘Se.’ This atomic sign is used when revealing a chemical reaction involving selenium or one of its compounds.

• The atomic mass, or weight, of selenium is 78.96.
• Selenium’s state at room temperature is strong.
• The melting point of selenium is 428 F (220 C), and its boiling point is 1,264.64 F (684.8 C).
• Selenium has lots of isotopes, however just 6 of them are known as stable isotopes.
• Selenium is positioned right listed below sulfur, and both elements share comparable physical along with chemical residential or commercial properties.
• There are lots of allotropes of selenium, however only 3 are well known. The very first one is amorphous selenium, which exists in powder and vitreous or glassy forms. While in the previous, it is red in color, in the latter phase it is black.
• Another allotrope of selenium is crystalline hexagonal selenium, which is thought about to be the most stable allotropic kind of selenium. This allotrope is metal gray.
• The third allotrope is crystalline monoclinic selenium, which exists in a deep red color.
• Selenium is organized as a chalcogen and is a non-metal.
• It can be found individually in nature, however it is frequently present as a substance such as zinc selenide or selenium dioxide.
• It is likewise a part of rare minerals like clausthalite.
• When it is used in chemical reactions, selenous acid is an efficient catalyst.
• Out of all the selenium substances, hydrogen selenide is the most hazardous one. It is present in gaseous type.
• Taking selenium supplements when it is already present in high quantities in your natural diet can lead to selenium poisoning.

Plants With High Quantities Of Selenium

Selenium’s natural abundance in the world can be discovered in lots of places. Research has found that levels of selenium are high in seafood and some kinds of organ meat. It is even present in the water that individuals drink in some locations.

If there is selenium present in the soil, it can affect the amount of selenium in the food that grows in it. This is further impacted by aspects such as the pH of the soil.

Veggies such as cauliflower, cabbage, and broccoli likewise have a high level of selenium existence.

Plants like Brazil nuts and garlic, when grown in soil that has a rich quantity of selenium, can collect the mineral too.

Some grains and cereals like wheat can have a relatively high content of selenium too. [6]

Use of selenium supplements

People can get selenium through multivitamins and other dietary supplements. These might consist of the mineral in different forms, consisting of selenomethionine and sodium selenate.

The Dietary Guidelines for Americans, 2020– 2025Trusted Source motivate individuals to get their nutrients from food sources instead of supplements. Eating a diverse and healthful diet plan is more vital than concentrating on specific nutrients as the key to good health.

When taking any supplement, it is necessary to purchase it from a credible source. In the United States, the Food and Drug Administration (FDA) does not monitor supplements for quality, purity, packaging, or strength. [7]

Indications of Selenium Deficiency You May Be Neglecting

Selenium Deficiency Symptom: You’re losing your hair

One of the most essential things on selenium’s to-do list: assist transform your T4 thyroid hormonal agent into the more active type called T3, describes Little. If you run low, you may experience symptoms of hypothyroidism, one of which is hair loss. “There can be lots of factors for loss of hair, so it’s your health practitioner’s job to understand what to check for,” says Small.

Selenium Deficiency Sign: You’re so exhausted

Another typical hypothyroid sign: tiredness. This may be a result of bad selenium levels slowing down your thyroid. “We want to knock out the apparent way of life aspects prior to taking a look at selenium,” says Small. That may be ensuring that your diet has sufficient levels of carbs, protein, and fat, searching for a vitamin D shortage, or examining iron levels. Then, make certain to follow these healthy routines for your thyroid.

Selenium Deficiency Sign: You’re gaining weight

When you experience unwanted weight gain, you’ll want to get to the source. Once again, your thyroid’s thirst for selenium might contribute, and repairing that insufficiency can assist your thyroid return online. Although Little first looks at diet when a client is gaining weight, she will think about testing selenium levels down the line. To find out why you’re loading on the pounds, consider these surprising reasons for weight gain.

Selenium Shortage Sign: You’re not functioning at your finest

Selenium is required to form selenoproteins, says Small, including glutathione peroxidase: “It is among the body’s primary ways to take harmful toxic substances and turn them into safe by-products,” she states. “Shortages in this can cause quite major health effects,” she notes.

Selenium Deficiency Sign: You might be at a greater risk for certain cancers

You’re most likely up for doing whatever you can to prevent cancer– and keeping optimal levels of selenium may reshuffle the deck in your favor. In a 2014 Cochrane Evaluation, scientists evaluated 55 observational studies to take a look at the link in between selenium and cancer. They found a 31 percent lower risk of cancer associated with greater selenium direct exposure, particularly with stomach, bladder, and prostate cancer. But other trials stopped working to show a benefit from selenium. Without concrete evidence, the authors conclude that supplements most likely aren’t the response. Rather, focus on the foods you can eat that will offer a series of health advantages, including selenium-rich foods like asparagus, broccoli, and mushrooms. And while you’re at it, you may wish to prevent these 10 unexpected things that can trigger cancer.

Selenium Deficiency Symptom: You’re sick all the time

Initially, make certain you’re washing your hands regularly, you got the influenza shot, and you’re sleeping long enough and peacefully (try these 13 tricks from sleep medical professionals). However you’re not doing yourself any favors if your selenium levels are low. “Without the ability to sufficiently make glutathione peroxidase, your body immune system can’t work appropriately, and you may discover you’re sick more frequently,” says Small.

Selenium Deficiency Sign: Your body is under a lot of stress

Selenium is an effective disease-fighting antioxidant. “Oxidative stress causes damage to cells throughout your body. Any time you can secure your cells from oxidative tension is an advantage,” says Small. Find go-to ways to simmer down in the moment, sleep enough to assist your body recuperate, and consume well– including getting enough selenium in your diet plan.

Selenium Deficiency Symptom: You have shortness of breath

Those selenoproteins have another important task: to protect your heart. A male who had Crohn’s disease recounted his case: He experienced inflamed legs and shortness of breath and it was later discovered that he had a selenium shortage that caused his heart failure. But the jury is still out on supplements: Although low selenium levels have been connected with a greater threat of cardiovascular disease, experts hesitate to advise taking selenium tablets. Rather, stick to a healthy, selenium-rich diet. [8]

Selenium adverse effects

Get emergency medical assistance if you have any of these indications of an allergy: hives; challenging breathing; swelling of your face, lips, tongue, or throat.

Long term use of high selenium dosages can lead to dangerous adverse effects. Stop taking selenium and call your physician at once if you have:.

• queasiness, vomiting;
• lack of energy, feeling irritable or very tired
• loss of hair, mild rash, fragile or uncomfortable fingernails, or white streaks on the nails;
• tremblings, feeling light-headed;
• muscle inflammation;
• flushing (heat, redness, or tingly feeling);
• metal taste, halitosis, strong body smell; or
• simple bruising or bleeding. [9]

Prior to Utilizing

Allergies

Inform your doctor if you have ever had any uncommon or allergic reaction to medicines in this group or any other medicines. Also inform your health care expert if you have any other types of allergies, such as to foods dyes, preservatives, or animals. For non-prescription products, read the label or package components thoroughly.

Pediatric

Problems in kids have actually not been reported with consumption of normal day-to-day advised amounts.

Geriatric

Problems in older grownups have actually not been reported with intake of normal daily recommended quantities.

Pregnancy

It is specifically crucial that you are receiving enough vitamins and minerals when you become pregnant which you continue to receive the right amount of vitamins and minerals throughout your pregnancy. The healthy development and development of the fetus depend upon a consistent supply of nutrients from the mom. However, taking large quantities of a dietary supplement in pregnancy might be hazardous to the mom and/or fetus and must be prevented.

Research studies in animals have actually shown that selenium triggers birth defects when given in large doses.

Breastfeeding

It is important that you receive the right amounts of vitamins and minerals so that your infant will likewise get the vitamins and minerals needed to grow correctly. Nevertheless, taking large amounts of a dietary supplement while breast-feeding may be harmful to the mother and/or child and should be prevented.

Drug Interactions

Although particular medications must not be used together at all, in other cases 2 different medications may be used together even if an interaction may occur. In these cases, your doctor might wish to alter the dosage, or other preventative measures might be required. When you are taking any of these medicines, it is specifically crucial that your healthcare expert know if you are taking any of the medicines listed below. The following interactions have actually been selected on the basis of their possible significance and are not always extensive.

Utilizing medications in this class with any of the following medicines is typically not advised, but might be required in some cases. If both medicines are prescribed together, your physician may alter the dose or how typically you use one or both of the medications.

Other Interactions

Certain medicines should not be utilized at or around the time of consuming food or consuming particular kinds of food since interactions may happen. Using alcohol or tobacco with particular medications may also cause interactions to occur. Talk about with your healthcare expert using your medicine with food, alcohol, or tobacco.

Other Medical Issues

The existence of other medical issues might affect making use of medicines in this class. Make certain you inform your doctor if you have any other medical problems, especially:.

Kidney issues or.

Stomach problems– These conditions might cause greater blood levels of selenium, which may increase the possibility of unwanted effects.

Dosing

The dosage medicines in this class will be various for different clients. Follow your medical professional’s orders or the instructions on the label. The following information includes just the average doses of these medications. If your dosage is various, do not alter it unless your physician informs you to do so.

The amount of medicine that you take depends upon the strength of the medicine. Also, the variety of doses you take each day, the time permitted between doses, and the length of time you take the medication depend upon the medical problem for which you are using the medication.

For selenium:.

For oral dose type (tablets):.

To prevent shortage, the quantity is based on typical day-to-day advised consumption:.

• Adult and teenage males– 40 to 70 micrograms (mcg) daily.
• Grownup and teenage women– 45 to 55 mcg daily.
• Pregnant females– 65 mcg per day.
• Breast-feeding females– 75 mcg each day.
• Kids 7 to 10 years of age– 30 mcg per day.
• Kids 4 to 6 years of age– 20 mcg daily.
• Kids birth to 3 years of age– 10 to 20 mcg each day.

To treat shortage:

Grownups, teens, and children– Treatment dosage is determined by prescriber for each individual based upon seriousness of deficiency.

Missed out on Dosage

If you miss a dosage of this medicine, take it as soon as possible. Nevertheless, if it is almost time for your next dosage, skip the missed dose and go back to your routine dosing schedule. Do not double doses.

Storage

• Stay out of the reach of kids.
• Shop the medication in a closed container at room temperature level, away from heat, moisture, and direct light. Do not cool. Keep from freezing.
• Do not keep outdated medicine or medicine no longer required. [10]

Conclusion

Selenium is a powerful mineral that is essential for the correct functioning of your body.

It plays a vital function in metabolism and thyroid function and helps secure your body from damage triggered by oxidative stress.

What’s more, selenium might assist improve your immune system, sluggish age-related psychological decrease, and even reduce your threat of heart disease.

This micronutrient can be discovered in a wide array of foods, from oysters to mushrooms to Brazil nuts.

Including more selenium-rich foods to your diet plan is an exceptional method to maintain health. [11]

Referrals

1. https://www.merriam-webster.com/dictionary/selenium
2. https://www.selenium.dev/history/
3. https://www.webmd.com/a-to-z-guides/supplement-guide-selenium#091e9c5e801b55ca-1-4
4. https://supplements.selfdecode.com/blog/health-benefits-selenium/
5. https://www.thoughtco.com/interesting-selenium-facts-609110
6. https://kidadl.com/fun-facts/22-selenium-facts-to-aid-your-child-s-interest-in-chemistry
7. https://www.medicalnewstoday.com/articles/287842
8. https://www.thehealthy.com/nutrition/selenium-deficiency-symptoms/
9. https://www.drugs.com/mtm/selenium.html#side-effects
10. https://www.mayoclinic.org/drugs-supplements/selenium-supplement-oral-route/side-effects/drg-20063649
11. https://www.healthline.com/nutrition/selenium-benefits#The-bottom-line