Want to know more about the essential trace element selenium? Then you've come to the right place! I will provide you with the most important information about this essential nutrient for humans. I'll start with a brief profile, cover the type, function, daily requirement, overdose and deficiency, and go on to the best sources of selenium and dietary supplements. You will also find out what vegans and vegetarians should know about selenium towards the end of the article.
Here is in advance a short Overview for you:
Notice: This article is not intended to replace medical advice, but merely to provide general information about selenium. Please consult your doctor if you feel unwell or want to prevent health problems with medical care.
Selenium PROFILE at a glance
Assignment: Essential trace element, semimetals category
Important for: Metabolism of thyroid hormones, immune system, antioxidant
Daily requirement: 70 µg (m), 60 µg (f) from the age of 15₁
Recording: by ingestion
Overdose: Oversupply possible, especially with high-dose supplements
Deficiency symptoms: including impaired thyroid function, susceptibility to infections, sleep disorders
Food: Brazil nuts, fresh porcini mushrooms, oat flakes, buckwheat
Food supplement: Mainly as capsules
What is the best way to absorb selenium?
Selenium is one of the nutrients that is very well absorbed by the body. For optimal absorption, it is important that you neither consume too little nor too much selenium. In this respect, selenium is similar to other nutrients such as Iodine or Ironwhich also have both a minimum and a maximum intake recommendation.
The Selenium content in food depends heavily on the soil. Selenium-rich soils also produce selenium-rich plants. Unfortunately, this means that selenium intake is often an estimate. Unfortunately, most soils in Europe are rather poor in selenium. Finland is an exception, because the soil there is specifically enriched with selenium.2 Other selenium-rich soils can be found overseas in Canada and the USA. Unfortunately, this is not ideal from an ecological point of view.
Good to know: Selenium-rich soils such as those in Finland, Canada and the USA are the basis for particularly selenium-rich foods.
What is the daily requirement of selenium?
The reference values (estimated values) published by the German Nutrition Society (DGE) are as follows 70 µg per day for men from the age of 15 and 60 µg per day for women from the age of 15.1 The National Institutes of Health recommend a daily intake of 55 µg from the age of 14, regardless of gender.3
For children and adolescents, the values for the recommended selenium intake do not differentiate between boys and girls:
|Children and teenagers
|1 to under 4 years
|4 to under 7 years
|7 to under 10 years
|10 to under 13 years
|13 to under 15 years
An increased intake of 75 µg per day is recommended for breastfeeding mothers.1
What does the body need selenium for?
Selenium is an important Antioxidantwhich protects the body from free radicals.2 In addition, the nutrient is also important for the Metabolism of the thyroid gland and the Immune system. In men it is also known as Building block for sperm needed. Selenium works anticarcinogenicin other words, anti-cancer. It also plays a major role in the Detoxification of heavy metals and environmental toxins.4
The functions of selenium at a glance:
- Antioxidant and anticarcinogenic effect
- Thyroid metabolism
- Strengthening the immune system
- Building block in sperm formation
- Detoxification of heavy metals and environmental toxins
Is an overdose of selenium possible?
As already mentioned, a corresponding Overdosing within the realm of possibility. The European Food Safety Authority (EFSA) has set a Tolerable Upper Intake Level (UL) of 300 µg per day.5 The National Institutes of Health give a little more leeway with 400 µg per day.3
An overdose can be caused by high-dose food supplements in particular. Another possibility for an overdose is the fluctuating selenium content of some foods. Brazil nuts, for example, are a good source of selenium, but their selenium content is subject to strong fluctuations. It is therefore possible that five or six Brazil nuts a day could already exceed the UL. If you eat 2-3 Brazil nuts a day, you are probably in the green zone. It would of course be desirable if the manufacturers could provide more precise information on the selenium content through analyses.6
Selenium deficiency risks
Selenium deficiency is mainly caused by insufficient selenium intake through the diet. The risk of a selenium deficiency can also lie in an increased requirement, which can be caused by diseases such as AIDS, hepatitis or cancer.
Symptoms of an undersupply of selenium can include susceptibility to infections, headaches or weight loss. More specific deficiency symptoms are Memory and sleep disordersthin hair and hair loss, as well as a Impaired thyroid function. A prolonged undersupply can lead to Keshan disease which is a disease of the heart muscle. The Kashin-Beck disease can also be caused by a persistent selenium deficiency and manifests itself in reduced bone growth and changes in the joints.7
Risk groups for a deficiency: People suffering from AIDS, hepatitis or cancer.
What are the best selenium sources?
In principle, the selenium content in food is heavily dependent on the soil and is therefore subject to strong fluctuations depending on where the food comes from. Therefore, the significance of the information on selenium content is limited. Nevertheless, there are of course foods that generally contain more selenium than otherse. Some examples of this are
- Brazil nuts (640 µg per 100 gram)
- Fresh porcini mushrooms (187 µg per 100 gram)
- Mackerel (39 µg per 100 gram)
- Chickpeas (4-30 µg po 100 gram)
- Oatmeal (10 µg per 100 grams)
- Buckwheat (8 µg per 100 grams)
Selenium supply with a plant-based diet
Selenium is defined by the DGE as a potentially critical nutrient in a vegan diet.8 I think that selenium is a nutrient, which can be critical for all population groups. This is mainly due to the fact that it is almost impossible for consumers to determine the selenium content of foods. You can roughly go by the country of origin and eat foods that may contain relatively high levels of selenium. Depending on the selenium content, you should be able to cover a good part of your daily requirement with two to three Brazil nuts a day.6
If you are eat a plant-based and wholesome diet and want to be on the safe side with your selenium intake, then here comes the point of dietary supplements for you.
How does selenium supplementation work?
Selenium supplementation can be useful if you suffer from a deficiency or are unsure whether you are meeting your daily selenium requirement. Before supplementing, you can take a Examination of your blood and have your selenium serum value determined. If this is below 50 µg/l, you are not optimally supplied with selenium. You can then try to replenish your selenium stores with one of the following selenium-containing multi-nutrient supplements. It is best to have your blood tested again after 6-12 months to see how your selenium stores have changed.
- Vegan multi-nutrient capsulesyou get here*
- An immune nutrient supplement with vitamin C, selenium, zinc and iron you get here*.
Ensure your selenium supply
If you want to optimize your selenium supply, it makes sense to take a look at the packaging of your food from time to time to check where it actually comes from. Selenium-rich soils can be found in Canada, the USA and Finland. In Europe - apart from Finland - the soils are unfortunately quite low in selenium, so you will either have to resort to food from far away or a dietary supplement.
You should also be aware that the information on the selenium content of foods varies greatly and always depends on the soil. In the case of animal foods, the selenium content depends heavily on the feed. Therefore, there is no really precise information that you can use to calculate your exact selenium intake. A rough estimate, which will usually put you in a solid range, is about 2-3 Brazil nuts per day.
If you have any questions or comments on the article about selenium, please leave a comment.
All the best,
PS.: You want to know, why i live vegan? I give you my reasons in the linked article. If you would like to know more about a healthy lifestyle, please continue your research with the article on Vitamin B12, Intermittent fasting or Salutogenesis away.
1 German Society for Nutrition e. V.: Selenium, https://www.dge.de/wissenschaft/referenzwerte/selen/?L=0. [02.06.2021].
2 Zentrum der Gesundheit: Selenium deficiency - cause of many complaints, https://www.zentrum-der-gesundheit.de/ernaehrung/mineralstoffe-spurenelemente/weitere-mineralstoffe-spurenelemente/selen, [02.06.2021].
3 National Institutes of Health: Selenium. Fact Sheet for Health Professionals, https://ods.od.nih.gov/factsheets/Selenium-HealthProfessional, [02.06.2021].
4 Center for Health: selenium detoxifies heavy metals and environmental toxins, https://www.zentrum-der-gesundheit.de/bibliothek/ratgeber/detox-uebersicht/entgiftung-mit-selen-ia, [02.06.2021].
5 European Food Safety Authority: Overview on Tolerable Upper Intake Levels as derived by the Scientific Committee on Food (SCF) and the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA), https://www.efsa.europa.eu/sites/default/files/assets/UL_Summary_tables.pdf, [02.06.2021].
6 N. Rittenau (2018): Goodbye vegan cliché! Scientific answers to critical questions about vegan nutrition. VENTIL-Verlag.
7 S. Schrör: Selenium deficiency, https://www.netdoktor.de/ernaehrung/selenmangel/, [02.06.2021].
8 Deutsche Gesellschaft für Ernährung e. V.: Position of the German Nutrition Society - Vegan Nutrition, https://www.dge.de/wissenschaft/weitere-publikationen/dge-position/vegane-ernaehrung/?L=0, [02.06.2021].