Selenium - Function and Requirement

Did you know that selenium is an essential trace element for humans? It is responsible for numerous functions in our body and ensures a strong immune defense. Selenium not only strengthens our cells, but also our hair and nails, and helps our body detoxify.

In this article, you will learn why selenium is so important for us, what a selenium deficiency can look like, and how you can easily meet your daily selenium needs.

What is selenium?

Selenium is an antioxidant and is responsible for several functions in our body. On the one hand, selenium is a component of the enzyme glutathione peroxidase, and on the other hand, it provides important trace elements and minerals. These help the body detoxify and thus ensure healthy bodily function. The enzyme glutathione peroxidase protects our cells from oxidative stress and thus from external damage.

Function and effect of selenium

This essential trace element is responsible for many functions in our body and supports several areas of our health. It is also vital for humans.

Selenium is found in both animal and plant foods and is also produced by the human body. It helps our body protect our cells from free radicals and thus strengthens our immune system. This can prevent cell mutations caused by cancer cells, which can protect us from some types of cancer. It can also reduce the risk of strokes or heart attacks. Our tissues are also protected and kept young thanks to a constant supply of selenium.

The thyroid gland is also supported and, together with iodine, helps to boost metabolism. Selenium is able to bind heavy metals and thus expel them from our body. 90% of toxins are then excreted through urine. This causes less damage to our body cells, which in turn stabilizes and strengthens them.

Another important function of selenium - especially in combination with zinc and biotin - is the strengthening and maintenance of our nails and hair.

Essentially, selenium secures our entire immune defense and protects us from hostile attackers that want to destroy our cells. At the same time, selenium, together with zinc and biotin, strengthens our hair and nails.

Daily selenium requirement

A selenium deficiency is rather rare here and usually only occurs in people who have problems absorbing this trace element. Those affected can, for example, be people with chronic bowel problems.

The DGE (German Nutrition Society) recommends different intake levels for various life situations. Infants need correspondingly less (10 µg per day) than adolescents (60 µg per day). From the age of 15, the DGE recommends 70 µg for men and 60 µg for women per day. Breastfeeding women need approximately 75 µg.

How you can cover your daily selenium needs with natural foods:

Table 1: Example calculation for a selenium intake of 60 to 70 µg per day

Source: Souci, S. W.: Die Zusammensetzung der Lebensmittel – Nährwert-Tabelle, Wissenschaftliche Verlagsgesellschaft Stuttgart, 2016, 8th edition

* Since the selenium content in food can vary greatly depending on the growing region, information on selenium content is limited in its validity.

What contains selenium?

Selenium is abundant in our foods. Very good selenium sources include meat, eggs, fish, asparagus, legumes, lentils, nuts, Brazil nuts (caution: do not eat too many, as they are contaminated with radioactive radium), cabbage vegetables, onion vegetables, brown rice, and millet.

The 6 best selenium sources (per 100 grams):

The selenium content in food depends on the selenium content in the soil. Due to climate change and changes in external environmental factors, the selenium content in our soils has decreased. However, heavy metals are increasingly found in the soil. In Europe, the selenium content in plant-based foods is therefore rather low. In the USA, on the other hand, the soils are richer in selenium and provide more for their plant-based foods than ours. Animal feed can be externally enriched with selenium, which means that animal foods, such as meat, contain more selenium than plants.

Symptoms of selenium deficiency

As already mentioned, a selenium deficiency is rather rare. Nevertheless, it can have serious consequences, which we would like to briefly address here.

A selenium deficiency can, for example, lead to thin and brittle hair or white spots on the nail surface. The immune system is weakened, and thyroid function can be impaired. It can also negatively affect male fertility by reducing sperm production. Further deficiency symptoms can be headaches, joint pain, sleep disturbances, or a general increase in the risk of infection.

Selenium supplementation

Since selenium deficiency could occur in our society, it is advisable to supplement selenium through dietary supplements if needed. The exact selenium level in the body can be determined by a simple blood test at your general practitioner's office. They will then also provide instructions on how much selenium should ideally be supplemented.

A balanced, colorful, and healthy diet is the be-all and end-all, but we can significantly improve our health by supplementing with selenium. We strengthen our hair and skin, protect our immune system, strengthen our cells, prevent fatigue and headaches, and support our cells in fighting free radicals.

However, too much selenium should not be supplemented, as this could have opposite effects.

Other interesting blog articles for you: 

Biotin - for skin, hair and nails

Dietary supplements for vegans

All our articles are written by nutritionists and checked for content quality by experts.