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Your hair seems unusually thin and pale? Your nails are covered with white spots and you constantly have new infections? These could be possible signs of a selenium deficiency. But don't panic: Such a deficiency can be quickly remedied with a change in diet or dietary supplements. You can find out everything you need to know in our selenium test 2021

We would like to make it easier for you to decide on the right selenium product and therefore present various options for supplementation in our selenium test 2021. We also highlight the possible advantages and disadvantages of selenium supplements. We also highlight the possible advantages and disadvantages of the respective products.

In our guide, we also explain to you which characteristics you can recognise in a selenium deficiency or a selenium overdose and what you can best do about it.




The most important facts

  • Selenium is an essential trace element that is mainly found in foods with a high content of animal and vegetable protein. It is also sold as a supplement in the food supplement industry and is suitable for people with a selenium deficiency. Before taking it, it is advisable to have the selenium level in the blood determined by a doctor.
  • The preparation is mainly produced in the form of capsules, tablets or in liquid form (drops). You can buy these in pharmacies, various supermarkets, organic food stores and drugstores, or order them from the comfort of your own home on the internet at Amazon or other online shops.
  • Selenium contributes to functions such as the maintenance of hair, nails or normal thyroid function, as well as to sperm formation in men.

The Best Selenium: Our Picks

Guide: Questions you should ask yourself before buying selenium

What is selenium?

Selenium is an essential trace element needed by the human body to maintain certain functions. It is normally consumed as part of a balanced and healthy diet through the consumption of certain foods.

Selenium is found in high amounts in animal and plant proteins. These include above all meat, fish, cereals, pulses and dairy products. Vegetables and lettuce, on the other hand, have a comparatively low selenium content.

To give you a rough overview, we have put together some examples of foods with a high selenium content:

food proportion of selenium in 100 g of the food
oatmeal 10 mcg
wheat bran 60 - 130 mcg
white beans 14 mcg
soybeans 19 mcg
salmon 26 mcg
tuna 82 mcg
Emmental cheese (45% fat) 11 mcg
Egg 20 mgc
Beef 35 mcg
Pork liver 58 mcg
Brazil nuts 100 mcg
White cabbage 3 mcg
Peppers 4 mcg

Why do you need selenium and what functions does it perform?

Since selenium is an essential trace element, your body needs it to fulfil various functions. This means that a selenium deficiency can occur if your intake is too low.

Within the EU, six different health claims have been approved for selenium on products about the function of selenium.

Selenium contributes to ...

  • normal sperm formation
  • the maintenance of normal hair
  • the maintenance of normal nails
  • normal function of the immune system
  • normal thyroid function
  • protection of cells from oxidative stress

Furthermore, selenium is said to have a preventive effect against cancer and heart disease and helps fight viruses.

There is a relationship between selenium concentrations in food and the incidence of breast cancer in humans. With the addition of selenium, there is a reduction in common mammary tumours. (1)

The aim of a study was to determine the effect of selenium during chemotherapy. Selenium is given orally as a medication. The patients concerned were those suffering from colorectal cancer.

The evaluations show that selenium and zinc supplementation can improve the clinical course of the general condition of patients with colorectal cancer. (2)

The aim of another study was to find out whether dietary selenium supplementation can even reduce the risk of cancer. The results showed that selenium supplements cannot influence the incidence of recurrent basal cell carcinoma of the skin.

However, selenium treatment was associated with a reduction in overall cancer mortality and the amount of lung, colorectal, prostate and total carcinomas. (3)

A randomised, double-blind, placebo-controlled trial involving 174 HIV-positive patients tested the effect of selenium. The patients who consumed selenium had an altered clinical picture.

Thus, the authors could hypothesise: Daily selenium administration can suppress the progression of HIV-1 viral load and provide an indirect improvement in CD4 count. The results support the use of selenium as a simple, beneficial and safe adjunctive therapy for HIV disease. (4)

What is your daily requirement of selenium and when is it best to take it?

The daily requirement of selenium varies mainly according to gender, body weight and age. As a guideline, 0.8 to 1 mcg of selenium per kilogram of body weight can be recommended for healthy people. Pregnant and breastfeeding women have an increased requirement compared to non-pregnant and breastfeeding women.

The following table summarises the estimated values of the European Food Safety Authority (EFSA) for the daily requirement of selenium:

Age (in years) Estimated daily requirement of selenium in mcg
0-6 months 0
7 months to 3 years 15
4-6 20
7-10 30
11-14 55
≥15 70

Note: There is no optimal time to take selenium in the form of a food supplement. Therefore, you can take it as you like, e.g. before a meal.

Who should take selenium as a food supplement in addition to their normal diet?

The dietary supplement should be taken by people who do not get enough selenium in their normal diet. I.e. people who have a selenium deficiency should take the supplement.

In particular, vegans and vegetarians, people with certain diseases (e.g. HIV or Cron's disease) have an increased risk of suffering from a selenium deficiency.

Verschiedene Nüsse mit Selen Selenium is found in various foods. But if you don't get enough selenium from your diet, you should take a replacement supplement. (Picture source: 123rf.com / 97697822)

However, the values given above are estimates, so experts are not yet in agreement about whether higher intakes of selenium have a better effect.

In addition to the recommended daily amount, the EFSA has also defined a tolerable total intake that will not cause any health damage in the long term. This is 300 mcg per day.

Another group of people who have an increased need for selenium are athletes, since the muscles are more stressed and minerals and trace elements are excreted from the body through sweat.

The supplement is also taken by bodybuilders in particular, as it helps with muscle regeneration and slightly increases testosterone levels.

Did you know that on average, women and men in Germany take too little selenium?

Women consume about 38 micrograms and men an average of 47 micrograms of selenium per day. A guideline for an optimal selenium supply per day is 30 to 70 micrograms.

We cannot speak of an undersupply, but the tendency is in this direction.

What symptoms indicate a selenium deficiency and what can you do about it?

Vegans and vegetarians as well as people with certain diseases (e.g. HIV or Crohn's disease) have an increased risk of selenium deficiency. The micronutrient is found in animal foods in particular. However, there are some vegan products that also have a high selenium content (see above).

The symptoms that indicate a selenium deficiency are manifold and can affect the whole body:

  • Hypothyroidism
  • Metabolic processes are slowed down
  • reduced quality of sperm in men
  • Impairment of hair (becomes thinner and paler) and nails (white patches)
  • Impaired immune defence; increased susceptibility to bacterial infections
  • Anaemia
  • Liver damage
  • Damage to nerves and muscles
  • Increased risk of cardiovascular disease (cardiovascular system)
  • Increasing the risk of prostate, ovarian, colon, breast and lung cancer

If you are not sure whether you are supplying your body with enough selenium, you can go to the doctor and have a blood test. The doctor will determine how high your selenium level is and whether you should change your diet or take a dietary supplement or medicine with a high selenium content.

chemie.deOnline Lexikon
Selenium deficiency diseases are extremely rare, but in countries such as North Korea and Northeast China, and occasionally in other countries, there is a selenium deficiency and this favours such diseases.

In Europe, there is usually no deficiency; only premature babies, parenterally fed patients and alcoholics can develop a deficiency.

(Source: chemie.de)

What side effects can it have in case of an overdose?

As described above, the EFSA has set the total tolerable intake at 300 mcg of selenium per day. Most dietary supplements and medicines containing highly concentrated selenium usually contain between 100 and 200 mgc.

If you follow the EFSA guideline and the recommendations on the packaging, there is no risk of side effects.

However, if you take more than the guideline value of 300 mcg, you may suffer long-term damage to your health. In the short term, an overdose can lead to fatigue, sensory disturbances, nausea and joint pain. In the long term, it can even lead to hair loss, poor nail formation, skin changes and neuronal damage.

Note: When taking supplements and medicines, do not exceed the recommended dosage on the packaging or in the package leaflet. To be on the safe side, you can ask your doctor to take a blood sample to determine your exact selenium level.

Decision: What types of selenium are there and which is the right one for you?

Basically, we distinguish between these types of selenium products:

  • Selenium in the form of capsules
  • Selenium in the form of tablets
  • Selenium in the form of liquid extract

In the following, we explain the different types and their respective advantages and disadvantages. In this way, we want to help you find the selenium product that is best for you.

What are the advantages and disadvantages of selenium in capsule form?

As already mentioned, most supplements with selenium are offered in the form of capsules. As these are filled with the concentrate by machine, the proportion of concentrated active ingredients is precisely determined and you do not have to measure for the correct dosage.

Another advantage of this type of product is that you can take it with some liquid at any time, even when you are on the go.

The capsule shell is made of different materials from product to product. Some make it from gelatine or microcrystalline cellulose (a non-water-soluble substance). However, some manufacturers also use water-soluble cellulose (HPMC) for the capsule shell, which is completely harmless due to its water-solubility.

Advantages
  • precisely measurable dosage
  • practical for on the go
  • no container needed for mixing
Disadvantages
  • Capsule shell often not vegan or made of additives
  • often contains other additives
  • may cause problems when swallowing

However, it often contains other additives as separating agents, fillers or binders. On the one hand, this can be described as a disadvantage, as gelatine is not suitable for vegans or vegetarians.

On the other hand, there is still no scientific consensus on whether the additives have a long-term negative effect on the human body.

Another disadvantage is that some people have problems swallowing capsules.

What are the advantages and disadvantages of selenium in tablet form?

The tablets are similar to the previous product type. They are also automatically dosed and you do not have to use a measuring cup or a scale to determine the amount to be taken. This means you are on the safe side with regard to overdosing, as long as you adhere to the EFSA reference values.

You can also conveniently take the tablets on the go. However, there is one difference to the capsule. No capsule shell is needed and at least for this one additive is omitted. Tablets are also usually smaller than capsules and therefore easier to swallow.

Advantages
  • no capsule shell
  • precisely measurable dosage
  • practical for on the go
  • no container needed for mixing
  • easier to swallow
Disadvantages
  • often contains additives (e.g. pressing and binding agents)

Nevertheless, tablets also often contain additives such as calcium phosphate. Although these are permitted in the food industry for the manufacture of products, nutrition experts consider them to be harmful to health if taken regularly.

What are the advantages and disadvantages of selenium in the form of liquid extract (drops)?

If you have problems swallowing tablets and capsules, liquid selenium extract is ideal for you. It is available in a bottle with a glass pipette, with which you can take any number of drops. With this type of product, you can determine the dosage yourself. However, you should make sure that you do not exceed the tolerable total intake.

Advantages
  • no capsule shell
  • fewer to no undesirable additives
  • usually vegan and suitable for members of certain religious communities
  • dosage can be determined by yourself using a glass pipette
  • easier to swallow due to liquid state
Disadvantages
  • Vessel needed to count the drops
  • if one miscounts, the exact dosage is not known
  • not tasteless

The drops usually do not contain any undesirable additives, which are used in the capsule for the shell and in the tablets as a pressing agent, among other things. They are also mostly vegan products, which are also suitable for vegetarians and members of certain religious groups.

When dosing, however, one should count the drops exactly. For this purpose, it is advisable to use a glass or other container so as not to miscount. Therefore, it is less practical for on the go compared to the previous types of products. In addition, the liquid extract is not tasteless and may not suit everyone's taste.

Buying criteria: You can use these factors to compare and evaluate products with selenium

In the following we will show you which criteria you can use to compare and evaluate selenium products. This will make it easier for you to get an overview and decide on a suitable and effective product.

In summary, these are the following criteria:

  • Suitable for vegans, vegetarians, allergy sufferers and followers of certain religious communities
  • Freedom from undesirable ingredients that are harmful to health
  • Price-performance ratio
  • Concentration level of the selenium preparation

In the following, you can read about the respective criteria and find out why it makes sense for you to purchase a product based on the criteria or not.

Suitability for vegans, vegetarians, allergy sufferers and followers of certain religious communities

As already mentioned in the previous chapters, supplements are often made with additional animal ingredients such as gelatine. For this reason, they are neither suitable for vegans and vegetarians nor for followers of certain religious communities and are therefore not suitable for everyone.

Schema mit Selen-haltigen Lebensmitteln Make sure you get enough selenium either in your diet or through substitutes. (Image source: 123rf.com / 87677818)

In addition, many supplement manufacturers often make protein powders or other supplements that are made from milk, soy or eggs. Since the same machines are used to produce these as are used to produce the guarana powder, it may contain traces of milk, soy or eggs.

Ranked products in this article will state on the packaging that these substances are not present in the product.

Freedom from undesirable ingredients that are harmful to health

In addition to selenium, many capsules and tablets contain additives that nutrition experts consider to be harmful to health when taken in high quantities or for which no long-term studies have been conducted on their long-term effects on health. These are mainly fillers, binders, anti-caking agents and colourings.

Microcrystalline cellulose is a fine plant fibre produced from plant waste by a chemical process. In tablets or capsules, these act as a pressing material or separating and flowing agent.

In principle, this substance is officially not considered harmful to health. However, if these fibres are small enough, they can penetrate the human body and cannot be processed further

As there are no long-term studies on the effects of this substance on health, it cannot be ruled out that health impairments can be triggered.

Did you know that a selenium deficiency can lead to increased tumour risk?

It has been discovered that a selenium deficiency can lead to tumours, especially in the gastrointestinal tract.

The situation is similar with the additive magnesium salts of fatty acids. Officially, the additive is approved by the authorities for production. However, since no long-term studies on the long-term effects of the substance are available yet, a health hazard cannot be completely ruled out.

Products containing these and other additives were rated negatively in the ranking and products containing no additives were rated positively.

Price-performance ratio

As with all products, however, the price-performance ratio also plays a role in the evaluation of product alternatives. Since the manufacturers sell the selenium preparation in different forms, quantities and dosages, the different products could not easily be compared directly with each other.

Therefore, for the ranking in this article, it was calculated for the respective products how much 100 mcg of selenium cost. After the conversion, the different products can be optimally ranked according to their price-performance ratio.

Concentration level of the selenium preparation

In previous chapters you have already been told that the EFSA has published an estimated value for the daily requirement of selenium, which is between 60 and 70 mcg for adults. In addition, a total tolerable intake of 300 mcg has been established. If this is exceeded in the long term, it can cause considerable damage to health.

Most selenium preparations are marketed with a single dose of 200 mcg. However, there are also some with 100 mcg or, especially with the drops, the possibility to determine the dose yourself (10 mcg per drop).

However, since the estimated daily requirement is far below 200 mcg, such products with 100 mcg were rated better, as they only minimally exceeded the estimated values and were thus more in line with the opinion of nutrition experts.

Note: When taking supplements, you should not exceed the recommended intake amounts on the packaging, otherwise you may experience side effects. It is also advisable to ask your doctor whether supplementation is necessary and sensible.

Trivia: Interesting facts about selenium

What are the benefits of selenium in pet food?

The essential trace element is not only needed by the human body but also by the animal body. Grazing animals such as horses often suffer from selenium deficiency. This is due to the fact that our soils in Europe do not contain enough selenium. Therefore, there is also a preparation for horses with the micronutrient in a high dosage.

Selenium fulfils the same functions in animals as it does in humans and it can also cause similar health problems if the intake is insufficient (selenium deficiency).

Image source: 123rf.com / 71895132

References (4)

1. K P McConnell, R M Jager, K I Bland, A J Blotcky. The Relationship of Dietary Selenium and Breast Cancer. J Surg Oncol. 1980; 15 (1), 67-70.
Source

2. A Federico, P Iodice, P Federico, A Del Rio, M C Mellone, G Catalano, P Federico. Effects of Selenium and Zinc Supplementation on Nutritional Status in Patients With Cancer of Digestive Tract. Eur J Clin Nutr. Apr 2001; 55 (4), 293-7.
Source

3. G F Combs Jr , L C Clark, B W Turnbull. Reduction of Cancer Mortality and Incidence by Selenium Supplementation. Med Klin (Munich). 1997 Sep 15; 92 Suppl 3, 42-5.
Source

4. Barry E Hurwitz, Johanna R Klaus, Maria M Llabre, Alex Gonzalez et al. Suppression of Human Immunodeficiency Virus Type 1 Viral Load With Selenium Supplementation: A Randomized Controlled Trial. Arch Intern Med. 2007 Jan 22; 167 (2), 148-54.
Source

Why you can trust me?

Wissenschaftliche Studie
K P McConnell, R M Jager, K I Bland, A J Blotcky. The Relationship of Dietary Selenium and Breast Cancer. J Surg Oncol. 1980; 15 (1), 67-70.
Go to source
Wissenschaftliche Studie
A Federico, P Iodice, P Federico, A Del Rio, M C Mellone, G Catalano, P Federico. Effects of Selenium and Zinc Supplementation on Nutritional Status in Patients With Cancer of Digestive Tract. Eur J Clin Nutr. Apr 2001; 55 (4), 293-7.
Go to source
Wissenschaftliche Studie
G F Combs Jr , L C Clark, B W Turnbull. Reduction of Cancer Mortality and Incidence by Selenium Supplementation. Med Klin (Munich). 1997 Sep 15; 92 Suppl 3, 42-5.
Go to source
Wissenschaftliche Studie
Barry E Hurwitz, Johanna R Klaus, Maria M Llabre, Alex Gonzalez et al. Suppression of Human Immunodeficiency Virus Type 1 Viral Load With Selenium Supplementation: A Randomized Controlled Trial. Arch Intern Med. 2007 Jan 22; 167 (2), 148-54.
Go to source
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