Feeling tired despite getting enough sleep, having brittle nails, or feeling constantly run down? A selenium deficiency could be to blame—but not necessarily. Precisely because the possible symptoms are so non-specific, it pays to take a careful, calm look at your diet, your current life stage, and, if necessary, your blood test results. After all, selenium is a trace element that the body only needs in small amounts, but it is involved in many fundamental processes.

What selenium does in the body

Selenium is a component of various enzymes and proteins. The so-called selenoproteins are particularly well known: they support antioxidant defense systems that protect cells from oxidative stress. Selenium also plays a role in the normal function of the immune system and the thyroid gland.

In the thyroid gland, selenium helps convert thyroid hormones and finely regulate metabolic processes. Adequate supply is also relevant for hair and nails. This does not mean, however, that more selenium automatically leads to shinier hair, more energy, or a stronger immune system. Nutrients work together. If you already have adequate supply, a high-dose supplement usually offers no additional benefit.

In the DACH region, the recommended reference values for adults are approximately 60 micrograms of selenium per day for women and 70 micrograms for men. Individual requirements may vary depending on diet, life stage, and health status. A balanced diet remains the most reliable foundation.

Selenium deficiency: Why supply can fluctuate

The amount of selenium in plant-based foods depends heavily on the soil in which they grow. European soils often contain less selenium regionally than soils in other parts of the world. This is why the selenium content of cereals, vegetables, or legumes can also vary significantly. If you eat a predominantly plant-based diet, you should be particularly mindful of your selenium intake—without turning it into a complicated calculation project.

A very one-sided diet, severely restricted calorie intake, or long-term digestive and absorption problems can also affect supply. In cases of chronic inflammatory bowel disease, celiac disease, or after certain surgeries, supplementation should always be medically supervised. The same applies to known thyroid conditions, pregnancy and breastfeeding, or if you regularly take medication.

Animal-based foods such as fish, eggs, meat, and dairy products provide relevant amounts of selenium depending on the product. Plant-based sources include whole grains, legumes, mushrooms, sesame seeds, sunflower seeds, and nuts. Brazil nuts are frequently mentioned as a source of selenium. However, their content fluctuates extremely: a single nut can already contain a lot of selenium. They are therefore not a precise tool for meeting a specific daily amount—and certainly no reason to eat large quantities.

Possible signs of selenium deficiency

A pronounced selenium deficiency is not common in Austria with a balanced diet. Nevertheless, low intake can occur. Possible signs are often not very clear and can have many other causes: persistent fatigue, increased susceptibility to infections, changes in hair or nails, muscle weakness, or concentration problems.

Especially in the case of diffuse hair loss or fatigue, it would be short-sighted to look only at selenium. Iron, vitamin B12, vitamin D, protein intake, stress, sleep, hormonal changes, and the thyroid gland can also play a role. Your body rarely sends a clear nutrient signal. Those who hastily combine several supplements risk confusion rather than clarity.

If symptoms persist for a longer period, it makes sense to speak with a doctor or a qualified nutrition professional. A laboratory value can help to better assess the situation. Important: blood values should always be evaluated in connection with symptoms, diet, and possible pre-existing conditions. A single value is not a diagnosis in itself.

How to strengthen your selenium supply in everyday life

The easiest way is not perfection, but variety on the plate. Regularly incorporate high-protein foods, whole grains, legumes, seeds, and nuts into your daily life. If you eat fish, it can also contribute to your selenium supply. With a vegan diet, it pays to take a conscious look at selenium-containing plant-based foods and the overall quality of your micronutrient routine.

It becomes practical when you do not view your meals as individual nutrient tasks. A warm porridge with nuts and seeds, a lentil salad with a whole-grain side dish, or a creamy shake as a complement to a balanced meal can be building blocks of a varied diet. Add sufficient protein, fresh vegetables, and healthy fats. This creates a routine that feels good and actually sticks in everyday life.

Those who have little time benefit from clear standards: a nutrient-rich breakfast, a wholesome main meal, and a sensibly planned snack instead of constant improvisation. At JOY NATURALS, this exact idea is at the center: natural ingredients and practical everyday rituals that complement—not replace—your diet.

Supplements: targeted instead of based on suspicion

A selenium supplement can make sense if insufficient intake is likely or if a deficiency has been medically diagnosed. The dosage should be based on the actual requirement. Selenium is not a nutrient for the motto “more helps more.”

Consistently too high an intake can have undesirable consequences. These can include nausea, a metallic or garlic-like breath odor, changes in hair and nails, or neurological symptoms. The European Food Safety Authority has set a tolerable upper daily intake of 255 micrograms for adults. This includes selenium from both food and supplements.

Therefore, look carefully at the label and avoid taking several products containing selenium simultaneously. A multivitamin supplement, a hair complex, and a separate selenium product can add up faster than you think. Quality is shown not only in a high dosage, but in transparent labeling, a traceable formulation, and a quantity that fits into a long-term, harmonious routine.

Be particularly careful with the thyroid gland and the desire for children

Selenium is often mentioned in connection with the thyroid gland and fertility. This does not mean that it replaces an independent therapy. In cases of Hashimoto's, hyperthyroidism, or hypothyroidism, diagnosis and treatment belong in the hands of a doctor. The same applies to the desire for children, pregnancy, and breastfeeding, where intake should be individually coordinated.

If you have laboratory values, bring them to the appointment and mention all supplements you use—including powders, drops, or beauty products. This clarity saves unnecessary duplication and creates a well-founded decision.

Your next sensible step

If you eat a balanced diet and have no risk factors, it is usually enough to focus on varied, nutrient-dense meals. In cases of a vegan or severely restricted diet, recurring symptoms, or a thyroid condition, a professional check can provide more certainty than self-diagnoses on the internet.

Health is not created by searching for the one magical micronutrient. It grows from small, reliable decisions: good food, conscious supplementation where it really fits, and the trust to take your own body seriously.