Selenium Health Benefits, Sources, and Side Effects

Selenium Health Benefits
Selenium Health Benefits, Sources, and Side Effects

Selenium is a trace mineral found naturally in soil. It is only required in trace levels by our bodies. Selenium is required for reproduction, thyroid gland function, infection resistance, DNA synthesis, and shielding cells from oxidative stress caused by free radicals.

The highest concentration of selenium is found in Brazil nuts. Other foods with reasonable quantities of selenium include nuts, seeds, meat, and cereals. To ensure that babies get enough selenium, infant formulae are supplemented with it.

The amount of selenium in food is determined by the soil in which it is grown. It was discovered in 1817 and was previously thought to be a tellurium compound.

However, due to its toxicity to industrial workers, it gradually received medical attention. Selenium has also been shown to be toxic to animals who eat high-selenium vegetables. As a result, an excess of this can be hazardous to one’s health.

Despite selenium’s favourable impacts on human health, it is critical to consume it in adequate proportions. Excessive selenium use, on the other hand, may have negative health consequences.

Selenium Health Benefits

Lowers the risk of prostate cancer

Many variables, including advanced age, obesity, and heredity, can all contribute to the development of prostate cancer. Furthermore, persons with prostate cancer may have loss of bladder control, erectile dysfunction, and other symptoms.

According to one study, appropriate selenium levels in the body minimise the chance of getting prostate cancer in men. Selenium helps to prevent prostate cancer by decreasing the growth and spread of cancer cells. The presence of selenium in the blood and tissues is inversely associated to the risk of prostate cancer.

Selenium has also been found in studies to lessen the risk of various other malignancies, including breast, colon, and lung cancer.

Selenium Has Antioxidant Properties

Toxins in the environment cause the formation of free radicals in our bodies. Furthermore, metabolic functions in the body make them. When these free radicals are produced in excess, they injure the tissues and organs.

Antioxidants are critical in minimising the damage produced by free radicals in the body. Selenium, for example, is a well-known antioxidant vitamin.

According to one study, selenium use may lower oxidative stress indicators. Furthermore, it improves antioxidative activity, minimising free radical damage.

Lowers the risk of heart disease

We know that heart disease is caused by bad eating habits, genetics, a lack of physical activity, smoking, excessive cholesterol levels, and a variety of other factors. If left untreated, it can lead to a variety of catastrophic health consequences such as stroke, heart failure, and so on.

Selenium consumption has been linked to a lower risk of heart disease in studies. Selenium is an extremely powerful antioxidant. It works on the heart by protecting it from the effects of free radicals.

Selenium also serves to reduce inflammation by limiting oxidative damage to lipids and artery blockage. As a result, selenium lowers the risk of heart disease and stroke.


Selenium Postpones the Onset of Alzheimer’s Disease

Alzheimer’s disease develops as brain function declines, resulting in memory loss. Lifestyle, environment, and genetics are the most prevalent causes of Alzheimer’s disease. As the illness progresses, it might make it harder to speak, learn, and remember.

Selenium in various stages has neuroprotective properties. According to one study, the antioxidant capabilities of selenium can protect the brain from free radical damage. As a result, it slows the progression of Alzheimer’s disease.

The Mediterranean diet, which is widely employed in the treatment of various ailments, includes foods high in selenium, such as nuts, seeds, and seafood. These meals can also help reduce the risk of Alzheimer’s disease.

Aids in the treatment of thyroid disorders

Thyroid hormone fluctuations cause hypothyroidism, Grave’s disease, Hashimoto’s thyroiditis, and other conditions. Furthermore, if your thyroid gland does not operate properly, your growth and development can suffer. For example, it can cause hair loss, weight loss, an irregular menstrual cycle, delayed growth, weariness, and other symptoms.

The thyroid gland has the highest concentration of selenium in its tissues. As we already know, metabolic actions such as thyroid hormone release can generate free radicals. The thyroid gland is protected from oxidative damage by selenium. According to one study, selenium may help with thyroid issues.

Helps to Reduce Inflammation

Selenium boosts the immune system. A study discovered that selenoprotein, which is generated from dietary selenium, lowers the inflammatory response.

These are linked to a variety of disorders, including allergies, asthma, and inflammatory bowel disease. It works by reducing immune system over-activation. It also boosts the body’s defences against infectious infections including influenza and tuberculosis.

Assists with Weight Loss

Unhealthy weight growth can lead to a variety of health problems, including obesity and heart disease. Selenium is essential for metabolism because it controls thyroid hormone activities and secretion.

According to one study, adequate selenium intake may aid in the maintenance of a healthy metabolic rate. As a result, adequate selenium intake leads to weight loss. However, when taken in excess of the recommended dose, selenium might have the opposite effect.

losing weight quickly

Selenium Promotes Skin Health

Exposure to sunshine, smoke, and other environmental contaminants is the leading cause of premature skin ageing. Acne, wrinkles, and dull skin might develop as a result.

Selenium has been shown in studies to be helpful in preventing and treating skin conditions such as psoriasis. It contains antioxidants. As a result, selenium shields the skin from the oxidative damage produced by sun exposure.

Prevents Premature Birth

During pregnancy, nutrients such as zinc, selenium, iron, and folate are critical for the baby’s healthy growth and development. According to research, selenium is essential for a baby’s healthy birth. Adequate selenium intake avoids negative pregnancy outcomes such as premature birth and foetal development limitation.

May Help Fertility

According to several studies, women who consume selenium have higher fertility. Furthermore, selenium promotes reproductive function by maintaining the health of follicular fluid. It can also help men improve their sperm count and motility.

Selenium Deficiency

Selenium is required for the healthy functioning of the thyroid gland and many other bodily processes. Selenium deficiency can disturb normal processes and result in:

  • Fatigue
  • Hair thinning
  • Fog in the mind
  • Immune deficiency
  • Muscle weakness
  • Infertility

Selenium shortage can result in a variety of diseases.

Keshan’s Illness

Keshan disease is a serious condition that, if left untreated, can result in cardiovascular disease, stroke, or death. Keshan illness can be treated or controlled, but it cannot be cured.

It is most common among women and children. According to research, it can be caused by a lack of selenium. It is sometimes coupled with microbial infection.


  • Nausea
  • Vomiting
  • Appetite loss
  • Dizziness
  • Chills
  • Heartbeat irregularity
  • Fatigue\sInflammation
  • Hair thinning

In the worst-case scenario, it could result in serious difficulties such as:

  • Coughing up blood
  • Extensive shortness of breath
  • Heart failure with congestive edoema
  • Fainting\sPalpitation
  • Stroke

Kashin’s Illness

It is a joint and bone condition caused by a lack of selenium. However, several variables contribute to the aetiology of this disease. It is more common among children. According to research, persons with this disease have limited growth and bone deformities.


  • Joint pain and stiffness
  • Unable to move joints
  • Joint enlargement
  • Selenium Intake Recommendation

People of all ages should consume the recommended amounts of selenium. It will aid in their appropriate growth and development. However, it is critical to avoid overconsumption. In addition, taking selenium with a meal is preferable to taking it on an empty stomach.

The suggested daily intake should be as follows:

  • 15mcg for ages 0-6 months
  • 20mcg: 7 months to 3 years
  • 30mcg for children aged 4 to 8 years
  • 9-13 years old: 40mcg
  • 55mcg for people aged 14 and up
  • Pregnant women should take 60mcg.
  • Women who are breastfeeding: 70mcg

Selenium Food Sources

Nuts from Brazil

They are high in antioxidants and minerals. Brazil nuts have the highest selenium level and a moderate zinc content. Furthermore, one study found that eating a single serving of Brazil nuts can significantly enhance the serum lipid profile of healthy participants.

This is due to the fact that they are nutritious and aid in the improvement of heart health. They also help other organs, such as the brain and kidneys, to work properly.

Nutritional Facts

According to the USDA, 100g of brazil nuts contains:

659kcals of energy
11.7g Carbohydrates
67.1g fat
160mg calcium
2.43mg iron
4.06mg zinc
1920g selenium


Tuna is a great source of high-quality protein. It is minimal in calories and fat and promotes muscular growth while decreasing body fat. Furthermore, they are incredibly nutritious, as they contain adequate levels of calcium, B complex vitamins, and so on.

Nutritional Facts

According to the USDA, 100g of tuna contains:

85 kilocalories
0.08g carbohydrate
0.6g fat
18mg calcium
1.67mg iron
0.66mg zinc
67.8g selenium


Turkey is another high protein, low carbohydrate dish. It is high in B vitamins, zinc, and selenium. It may be a tasty and healthful side dish to almost any lunch entrée.

Nutritional Facts

According to the USDA, 100g of turkey contains:

213kcals of energy
0g Carbohydrates
27.1g protein, 10.4g fat
31mg calcium
1.56mg iron
3.77mg zinc
28.4g selenium

Cottage cheese

Curd cheese, such as cottage cheese, is a form of curd cheese. It’s delicious and nutritious, with low fat, high protein, selenium, calcium, and a variety of other nutrients. You can use them in salads, eggs, toast, and a variety of other dishes.

Nutritional Facts

According to the USDA, 100g of cottage cheese contains:

82 kcals of energy
4.31g carbohydrate
11g protein
2.3g fat
103mg calcium
0.13mg iron
0.61mg zinc
14.6g selenium

Sunflower Seeds

Sunflower seeds aid in the regulation of the menstrual cycle, the prevention of heart disease, and the enhancement of immunity. They are, nevertheless, heavy in calories and should be used in moderation.

Nutritional Facts

According to the USDA, 100g of sunflower seeds contain:

657kcal of energy
17.1g carbohydrate
21g protein
56.1g fat
78mg calcium
5.2mg iron
6mg zinc
80.4g selenium

Selenium Potential Side Effects and Precautions

It is best to use selenium supplements under the supervision of a doctor. It is, nonetheless, critical to use caution. The safe upper limits for intake should not be exceeded. These top limitations are as follows:

  • 45mcg for ages 0-6 months
  • 46mcg (7-12 months)
  • 90mcg for ages 1-3 years
  • 150mcg for children aged 4 to 8 years
  • 9-13 years old: 280mcg
  • 400mcg for people aged 14 and above

Thyroid Issues

Taking selenium may aggravate hypothyroidism. It is most common in people who are iodine deficient. In this instance, iodine and selenium should be taken simultaneously. Consult your doctor for the proper dosage and therapy.

Motility of Sperm

Though studies show that selenium increases fertility, it is important to recognise that ingesting too much selenium can have the opposite effect. It is because selenium reduces the ability of sperm to travel, reducing fertility. Consume selenium only within the tolerated upper limits.

Kidney Disease Can Be Caused By Selenium

Excessive selenium consumption may be detrimental to the kidney. As a result, it is critical for patients with kidney failure or those undergoing dialysis to ingest selenium within safe levels. Excessive selenium consumption has been linked to acute renal failure in studies.


According to case studies, high levels of selenium ingestion may result in congenital defects in newborns. It may potentially cause pregnancy difficulties. As a result, it is critical to take selenium within safe levels.

Additional Medications

When taken concurrently, selenium supplements can interfere with a few drugs. Warfarin is one such medicine. According to research, selenium may affect the activity of warfarin. As a result, it would be beneficial if you discussed this with your doctor before to intake.


According to research, selenosis is caused by a high selenium intake. It could be attributable, for example, to increasing consumption of selenium-rich foods like brazil nuts. It may also occur as a result of foods grown in soil rich in selenium or from excessive selenium supplementation.


Nail discoloration Brittle nails
Hair thinning
Bad odour, sometimes known as ‘garlic breath.’

In conclusion

Selenium is essential for our bodies’ day-to-day operations. Excessive selenium use, on the other hand, can be detrimental. Both selenium deficiency and toxicity can lead to negative health effects.

As a result, it is critical to use caution while selecting a selenium supplement. Always see a physician before using a supplement to discuss the advantages and potential adverse effects. It is also critical to avoid any medicines that may interact with selenium supplements.

Frequently Asked Questions (FAQs)

What is the function of selenium in the body?

A. Selenium is essential for the healthy functioning of the thyroid gland, the reproductive system, and the immune system. Furthermore, it aids in the improvement of skin and heart health, as well as the improvement of skin.

Is it safe to consume selenium on a daily basis?

A. Yes, you can safely take selenium every day as long as you stay within the tolerated upper limit. The body may be harmed if the safe limit is exceeded. It may cause nausea, vomiting, agitation, and other side effects.

What are the signs of a lack of selenium?

A. Selenium deficiency symptoms include low immunity, hair loss, muscle weakness, nausea, vomiting, exhaustion, infertility, and brain fog.

How much selenium should you take on a daily basis?

A. You can obtain enough selenium by eating selenium-rich foods such brazil nuts, chicken, turkey, and tuna. The suggested dosage varies according to age and medical condition. It goes like this:

  • 15mcg for ages 0-6 months
  • 20mcg: 7 months to 3 years
  • 30mcg for children aged 4 to 8 years
  • 9-13 years old: 40mcg
  • 55mcg for people aged 14 and up
  • Pregnant women should take 60mcg.
  • Women who are breastfeeding: 70mcg

What are the disadvantages of selenium?

A. When consumed in moderation, selenium provides a variety of health benefits. Increased selenium intake, on the other hand, can cause negative health effects such as bad odour or “garlic breath,” nail discoloration, brittle nails, nausea, vomiting, exhaustion, and hair loss.

Does selenium contribute to weight gain?

A. No, taking proper levels of selenium aids in weight loss. It is because selenium regulates thyroid function and metabolism. However, some studies have found that consuming too much selenium might lead to weight gain.

What foods contain a lot of selenium and zinc?

A. Selenium-rich foods include brazil nuts, chicken, turkey, tuna, and cottage cheese. Furthermore, foods high in zinc include meat, seafood, legumes, seeds, nuts, dairy, and some vegetables.

Is selenium good for sperm production?

A. Yes, studies have shown that getting enough selenium helps boost sperm motility and count in men. Furthermore, selenium promotes reproductive function by maintaining the health of follicular fluid.

Is it possible for selenium to increase PSA?

A. No, studies have shown that consuming adequate levels of selenium can lower PSA, lowering the risk of prostate cancer.

Is selenium beneficial to the prostate?

Yes, selenium both delays and lowers the chance of prostate cancer. It works by stopping malignant cells from spreading to other organs and tissues. The presence of selenium in the blood and tissues is inversely associated to the risk of prostate cancer.

When is the optimum time to take selenium?

A.You can take it whenever you want. However, selenium supplements should be taken with other foods rather than on an empty stomach.

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