Selenium Benefits for Metabolism and Health (+ Food Sources)

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Vitamin D is widely debated in the health community for its importance to the human body. But today I want to talk about another nutrient that is often forgotten. Selenium Selenium is an important nutrient for metabolism and overall health, but not many people know much about it (or why it is so important).

What is selenium?

Selenium is a mineral that is important for overall health. Selenium deficiency is rare in the United States, but it is a growing problem in some parts of Europe and other parts of the world. Also, selenium deficiency (not getting enough selenium, but not deficiency) can be a problem.

I published an article Microbial environment in health and disease Selenium deficiency is reported in 500 million to 1 billion people worldwide. Not even enough selenium is available for maximum health (although they are not technically deficient).

How selenium benefits the body

Selenium is a powerful antioxidant that affects many functions in the body:

Reduces the risk of cancer

Some research suggests that adequate selenium levels may have a protective effect against cancer. A 1996 study of double-blinds (neither the researchers nor the participants knew who was taking selenium and who was getting a placebo) found that selenium levels significantly reduced the risk of dying from cancer and complete cancer incidence. Linked to danger. Because of this significant difference, the blind part of the trial was soon over. This means that researchers no longer considered it ethical to assign placebo to some people.

According to the Physicians’ Committee for Responsible Medicine, selenium helps protect against cancer in the following ways.

  • Antioxidants help fight free radicals that damage cells
  • Slows down tumor growth
  • Speed ​​of cancer cell removal

Although this important study is quite old, new research supports its discovery. A 2016 meta-analysis found that high levels of selenium in the diet were linked to a reduction in cancer risk.

Improves thyroid and metabolism

Vital thyroid function is essential for healthy metabolism. Selenium plays an important role in thyroid health.

In fact, there is more selenium per gram in the thyroid anywhere in the body.

The synthesis of thyroid hormones (T4) produces many free radicals that can compete with selenium. Without selenium to do this, oxidative stress (and related issues) can occur.

Selenium is also needed for hormone regulation. T4 is not biological unless it is processed by a special enzyme and converted to T3. Selenium is needed for these enzymes to work properly.

T3 is what determines the body’s metabolic rate. If anything goes “wrong” during this complex process, thyroid and metabolic function may suffer.

In addition, many people with Hashmoto’s disease (autoimmune thyroid condition) cannot tolerate iodine. But iodine is an essential nutrient for thyroid hormone synthesis! The idea is that iodine supplementation reduces an important enzyme required for T4 / T3 conversion. Obviously, this creates a problem. But a systematic study suggests that lowering the amount of selenium in thyroid antibodies may be helpful in Hashmoto’s disease. Perhaps this is because selenium helps fight free radicals produced during T4 synthesis.

Bottom line: Selenium levels can help alleviate Hashmoto’s symptoms and issues related to iodine intake. But always consult your doctor. For Hashimoto’s patients, there is a delicate balance between too much and not enough selenium and iodine.

Reduces infertility

There has been a lot of research around male fertility and selenium levels. Most of them say that one of the reasons for male infertility is selenium deficiency. A study published in Lancet It shows that selenium improves male fertility with the help of sperm motility.

Despite this, less attention is being paid to the amount of selenium and fertility of women. Selenium deficiency can lead to infertility, miscarriage, preeclampsia, fetal restriction, premature labor, gestational diabetes, and maternal cholestasis (liver and bile problems) in men and women, according to a study. Is. This is a particularly interesting finding, considering that many of these cases are not easily attributed to any cause.

Helps in detoxification

Selenium is an important building block in the production of glutathione. Glutathione is a “master antioxidant” that helps the body produce and recycle antioxidants. It is very important for cellular health. It also binds heavy metals and other toxins and helps the stool to get out of it. There is a lot of research showing that the amount of selenium can help detoxify heavy metals.

Can reduce heart disease

The importance of selenium in reducing oxidative stress is thought to be one of the reasons that selenium may be helpful in reducing heart disease. According to a 2001 study, selenium has also been shown to reduce inflammation, prevent the oxidation of cholesterol particles, and prevent blood platelets from clumping.

However, research focusing on the direct relationship of selenium to heart disease is contradictory. A 2006 study found no link between selenium levels and heart disease. The meta-analysis concluded that low selenium concentration was associated with heart disease. However, more research is needed.

A study published in International Journal of Cardiology Concomitant selenium and CoQ10 supplementation has been shown to have a significant effect on reducing heart disease mortality. So maybe the combination of these two supplements is the key.

Improves the functioning of the immune system

Selenium is incredibly important for immune function, but it is not fully understood how it works. What we do know is that selenium deficiency lymphocytes (white blood cells of the immune system) are less capable of proliferating in response to cell division. Also, selenium helps the body remove toxins and fight free radicals. This reduces the burden on the defense system.

Viral and bacterial infections can be more serious in the presence of selenium deficiency. For example, benign strains of Coxsackie and influenza viruses can turn into highly pathogenic strains. In addition, people with HIV saw an improvement in treatment with selenium supplementation.

A sign of selenium deficiency

It is usually easy to get selenium from a healthy diet, but in some cases, selenium may be in small amounts in foods grown in poor soils. In the United States, selenium is generally high in soil (except in some places, including the North West and New England).

Symptoms of deficiency include:

  • Abnormalities of skin, nails, hair and blood cells
  • Male infertility
  • Heart disease
  • Arthritis (Cashin’s disease)

People at high risk for selenium deficiency live in areas that are deficient, undergoing kidney dialysis, HIV positive, or those whose diet is primarily processed food (processing selenium destroys). she does).

Selenium deficiency or insufficiency is often more effective in people with other health problems. Selenium deficiency causes biochemical changes that can lead to certain diseases in people. In addition, selenium deficiency can exacerbate iodine deficiency.

Symptoms of selenium poisoning

Selenium is an important nutrient for maximum health, but can also be very harmful. The process of balancing selenium is very delicate. I would not recommend completing without first consulting your doctor. Selenium from food sources should be fine if you are eating a balanced diet.

Selenium can cause toxicity:

  • Garlic breath
  • Nausea
  • Diarrhea
  • Itchy skin
  • Irritability
  • Metallic taste in the mouth
  • Broken hair or nails
  • Hair or nail damage
  • Colored teeth
  • Nervous system problems

Severe symptoms include difficulty breathing, tremors, kidney failure, heart attack, and heart failure.

Food sources of selenium

Unlike most other vitamins, selenium can be toxic at relatively low levels. That’s why it’s especially important to take selenium from food instead of supplements. Fortunately, as long as you live in an area where the soil is low in selenium, it is easy to get enough selenium in whole foods. Here are some of the best sources.

  • Brazil Nuts – The best source of selenium, Brazil nuts contain selenium at an average cost of about 2 days per nut (RDA for selenium is about 55 mcg).
  • Mushroom
  • Garlic
  • Onion
  • Broccoli
  • Spinach
  • Brussels sprouts
  • Insulated white
  • Sunflower seeds
  • Chia seeds
  • Pasture increased poultry
  • Beef fed grass
  • Pasture eggs
  • Sardines
  • Wilde grabbed the salmon
  • Halibut
  • Lamb or beef liver

The best way to add selenium to your diet is to look for natural food sources and eat several of them each week. Shopping for food or produce delivery in season can be a great solution.

As always, it’s best to balance and individualize the diet to suit your needs (maybe under the care of a nutritionist or doctor if you have a thyroid or other condition)!

The article was reviewed medically by Dr. Lauren Jeffers, a Certificate in Admissions Medical and Pediatrics. As always, this is not personal medical advice and we recommend that you talk to your doctor or work with a doctor at Study MD.

Have you increased your selenium intake? What have you seen about your health?


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