Selenium Deficiency — Symptoms & Importance of this Trace Element

What Is Selenium?

Selenium is an essential trace element that plays a crucial role in your body. Although it is only needed in very small amounts, it is best known for being a component of selenium-containing proteins (selenoproteins), essential enzymes in your body. Selenium is crucial for healthy thyroid function, for example, and it supports the immune system and can reduce inflammation in the body. [1]

In short, selenium is a vital trace element that has a major impact on your health – even in tiny quantities.

What Function Does Selenium Have In The Body?

Selenium performs some fundamental tasks in your body that are essential for your health and survival. One of the main functions of selenium is its role as a component of selenoproteins, which act as antioxidant enzymes.

Antioxidant enzymes protect your cells from oxidative stress by neutralizing free radicals that could otherwise cause cell damage. This means that selenium helps to keep your cells young and healthy, reducing the risk of chronic diseases. [1]

In addition, selenium plays a vital role in your thyroid function. It helps convert thyroid hormones into their active form, which is essential for a healthy metabolism and hormone balance.

A well-functioning metabolism ensures that you have enough energy, can regulate your body temperature, and keeps your weight in balance.

Selenium also supports your immune system and helps your body control inflammation and fight infections. As you can see, selenium is a real all-rounder that maintains and promotes your health in various ways.

Why Is A Selenium Deficiency Dangerous?

A selenium deficiency can lead to various health problems. As selenium plays a central role in the antioxidant protection system, a deficiency can increase oxidative stress. [1]

High oxidative stress means that your cells become more susceptible to free radical damage, which can lead to premature aging and an increased risk of chronic diseases such as cardiovascular disease and cancer. [1]

Another problem caused by selenium deficiency affects thyroid function. Without enough selenium, your body cannot effectively metabolize thyroid hormones, which can lead to hypothyroidism.

Hypothyroidism often manifests itself in symptoms such as fatigue, weight gain, sensitivity to colds, depression, and even aggressive behavior. [1]

Selenium deficiency is particularly worrying for pregnant women, as it can increase the risk of miscarriage and developmental disorders in the fetus.

The immune system also suffers from a selenium deficiency, which can increase your susceptibility to infections.

Keshan Disease

If your selenium deficiency is particularly severe and persists over a long period, you may develop Keshan disease.

Keshan disease is a rare form of cardiomyopathy (disease of the heart muscle) and is caused by a severe selenium deficiency that leads to impaired heart muscle function. [2]

This deficiency weakens the immune system and increases susceptibility to viral infections, which can further aggravate heart damage.

What Symptoms Can Occur With A Selenium Deficiency?

A selenium deficiency can manifest itself in many ways, as it is involved in many important processes in your body.

Here are some of the most common low selenium symptoms and signs of selenium deficiency: [1]

1. Fatigue and Weakness

If you feel exhausted all the time, a selenium deficiency could be the cause. Since selenium is necessary for healthy thyroid function, a deficiency can interfere with the production of thyroid hormones, leading to hypothyroidism.

Thyroid hormones are crucial for energy metabolism, and their deficiency can lead to persistent fatigue and physical weakness.

2. Hair Loss

Selenium is of vital importance for the health of your hair. A deficiency can cause your hair to thin or even fall out.

This is also related to thyroid function, as insufficient production of thyroid hormones can negatively affect hair growth.

3. Weakened Immune System

Selenium plays a crucial role in supporting the immune system. With a deficiency, selenium-dependent enzymes cannot optimally fulfill their task of protecting your cells from damage and inflammation.

This can make you more susceptible to infections and take longer to recover from illness. Intestinal diseases, which are often related to the immune system, can, therefore, also be caused or promoted by a selenium deficiency.

4. Cognitive Impairment

A selenium deficiency can also impair your brain's performance. Studies have shown that low selenium status is associated with reduced cognitive function and an increased risk of neurodegenerative diseases such as Alzheimer's. [3]

If you have difficulty concentrating or notice memory problems, a selenium deficiency could be a possible cause.

5. Muscle Pain and Weakness

Selenium is important for the health of your muscles. A deficiency can lead to muscle pain, muscle weakness, and even muscle breakdown.

This is because selenium plays a role in the repair and protection of muscle tissue.

6. Fertility Issues

Selenium is also highly beneficial for your reproductive health. A deficiency can lead to fertility problems in both men and women.

In men, low selenium status can affect sperm quality, while in women, the risk of pregnancy complications can be increased.

7. Dry and Flaky Skin

Your skin can also suffer from a selenium deficiency. Dry, flaky skin or even eczema could indicate that your body lacks this critical trace element. As selenium has an antioxidant effect, it also helps to protect skin cells.

What Is the Daily Selenium Requirement?

The daily selenium requirement varies depending on age, gender, and circumstances, but a daily intake of around 60–70 micrograms (µg) is generally recommended for adults. [4]

Here is an overview of the reference values for selenium according to the German Nutrition Society:

• Infants (0 to under 4 months): 10 µg per day
• Children (4 to under 12 months): 15 µg per day
• Children (1 to under 4 years): 15-20 µg per day
• Children (4 to under 7 years): 20-30 µg per day
• Children (7 to under 10 years): 30-45 µg per day
• Children (10 to under 13 years): 45-60 µg per day
• Adolescents (13 to under 15 years): 60 µg per day
• Adolescents aged 15 and over and adults (male): 70 µg per day
• Adolescents aged 15 and over and adults (female): 60 µg per day
• Breastfeeding women: 75 µg per day
• Pregnant women: No increased reference value, same recommendation as for non-pregnant women (60 µg per day)

Please bear in mind that a balanced diet is usually sufficient to ensure adequate selenium intake.

However, suppose you belong to a risk group, for example, due to particular dietary habits, intolerances, certain health conditions, or pregnancy. In that case, monitoring your selenium levels and changing your diet may make sense.

Talk to one of our health coaches who can give you tips on your eating habits based on your health data.

Which Foods Are High In Selenium?

The following foods and food groups are known to be particularly rich in selenium: [5]

1. Brazil nuts: Brazil nuts are by far the richest natural source of the trace element selenium. Just one Brazil nut can meet or even exceed your daily selenium requirement. The Brazilian nuts contain around 68-91 µg of selenium per nut, making them a real superfood for selenium intake.
2. Fish and seafood: Fish species such as tuna, salmon, sardines, and herring, as well as seafood such as oysters and prawns, are also very rich in selenium. For example, a portion of 100 grams of tuna provides around 80-90 µg of selenium.
3. Meat and poultry: Offals such as liver and kidneys and also muscle meat from beef, pork, and chicken are excellent sources of selenium. A 100-gram piece of chicken breast contains around 20-30 µg of selenium.
4. Eggs: Eggs are a versatile source of selenium. A large egg contains about 15-20 µg of selenium, about a third of your daily requirement.
5. Whole grain products: Whole grain products such as wheat, barley, and oats also contain selenium, but in smaller amounts. The selenium content can vary depending on the type of soil on which the grains were grown.
6. Dairy products: Milk and dairy products such as cheese and yogurt also provide selenium but in moderate amounts. A glass of milk contains about 8-10 µg of selenium.
7. Legumes and nuts: Besides Brazil nuts, other nuts such as walnuts and almonds and pulses such as lentils and beans also contain smaller amounts of selenium.

Our insider tip: A combined intake of selenium and vitamin C can be powerful, as vitamin C and selenium work together synergistically to strengthen your antioxidant defenses and support your immune system. So drizzle a little lemon juice on your chicken breast or fish to biohack your nutritional intake.

The same applies to vitamin E. This is because selenium-dependent enzymes (such as glutathione peroxidase) and vitamin E work together to protect cell structures and support the function of the immune system.

So if you eat foods containing vitamin E, e.g., sunflower seeds, together with foods containing selenium, both nutrients benefit from each other and develop their full effect.

Selenium-rich foods offer a natural way to cover your selenium supply.

When Should I Take Selenium Supplements?

Selenium supplements should only be used if you have a selenium deficiency that cannot be corrected by a balanced diet.

You can also consider selenium supplements if you live in a region known for selenium-poor soils. Selenium-poor soils imply that plants that grow in these soils, or animals that feed on these plants, contain or consume less selenium.

People who live mainly on food from such regions are at a higher risk of selenium deficiency, as their diet does not provide sufficient selenium. For example, regions with selenium-poor soils can be found in parts of China, particularly in the Keshan Province, where Keshan disease gets its name.

Other areas with selenium-poor soils can be found in other parts of China, Scandinavia, Eastern Europe, and New Zealand.

How Can I Prevent Selenium Deficiency?

Fortunately, you can prevent a selenium deficiency relatively easily. The daily requirement for selenium is around 60–70 micrograms for adults.

• Get selenium through your diet: A balanced diet is the key to preventing a selenium deficiency or restoring your selenium levels.
• Selenium is found in many foods, such as Brazil nuts.
• Fish, meat, eggs, and wholegrain products are also good sources of selenium.
• Vegetarians and vegans should pay particular attention to their selenium intake and enrich their diet with sufficient sources of selenium so that they consume enough selenium-containing foods.