Selenium deficiency - symptoms, causes and treatment

What is selenium deficiency and how much selenium do you need every day?

Selenium deficiency is a widespread phenomenon that occurs when your body is not supplied with enough of the essential trace element selenium. Selenium is an essential component of numerous enzymes and proteins that play a crucial role in maintaining various bodily functions. According to the German Nutrition Society (DGE), the recommended daily intake is 30-70 μg for adults, with women tending to have a slightly lower requirement than men. During pregnancy and breastfeeding, the selenium requirement increases to 60-70 μg per day. Insufficient selenium intake over a longer period of time can lead to selenium deficiency, which can be associated with various symptoms and health impairments.

Selenium deficiency symptoms

The symptoms of selenium deficiency are varied and often unspecific, which can make diagnosis difficult. The most common signs include:

• Fatigue and exhaustion: Chronic selenium deficiency can lead to persistent tiredness and reduced performance, as energy production in the cells is impaired.
• Muscle weakness and pain: Selenium is essential for muscle health. A deficiency can lead to muscle weakness, cramps and pain.
• Hair loss and brittle nails: Hair follicles and nail cells need selenium for healthy growth. A deficiency can lead to increased hair loss, brittle nails and a dry, flaky scalp.
• Impaired immune system: Selenium is essential for the functioning of the immune system. A deficiency increases susceptibility to infections and diseases.
• Thyroid problems: The thyroid gland contains the highest concentration of selenium in the body. A selenium deficiency can contribute to an underactive thyroid (hypothyroidism) and an enlarged thyroid (goitre).
• Fertility problems: In both men and women, a selenium deficiency can affect fertility by impairing the quality of sperm and eggs.

Causes of selenium deficiency

There are various factors that can contribute to a selenium deficiency:

• Low selenium diet: The main reason for a selenium deficiency is insufficient dietary intake. People who have an unbalanced diet or do not eat selenium-rich foods are particularly at risk.
• Vegan and vegetarian diets: Plant-based foods often contain less bioavailable selenium than animal products. Strict vegans and vegetarians have an increased risk of selenium deficiency.
• Malabsorption: Diseases of the digestive tract such as coeliac disease, chronic inflammatory bowel disease or pancreatic insufficiency can impair the absorption of selenium.
• Smoking and alcohol consumption: Smoking and excessive alcohol consumption increase oxidative stress in the body and lead to an increased selenium requirement.
• Regional differences: The selenium content in plant foods depends on the selenium content of the soil. In some regions of the world, such as parts of Europe, the selenium content of soils is naturally low.

Impact of selenium on weight

Selenium plays an important role in regulating metabolism and can therefore also influence body weight. Studies have shown that a selenium deficiency can be associated with overweight and obesity. This can be explained by the fact that selenium, as a component of enzymes, is involved in the activation of thyroid hormones, which in turn regulate the basal metabolic rate and fat burning. A selenium deficiency can therefore lead to a slower metabolism and make it more difficult to lose weight. As an antioxidant, selenium is also involved in combating oxidative stress, which is also associated with obesity. A sufficient supply of selenium can therefore help to optimise the metabolism and support healthy weight regulation.

Effects of selenium in women

Selenium is particularly important for women as it supports various female-specific functions:

• Fertility: Selenium is involved in the production of oestrogen and progesterone and therefore helps to regulate the female cycle. A selenium deficiency can impair fertility and increase the risk of miscarriage.
• Pregnancy and breastfeeding: The need for selenium is increased during pregnancy and breastfeeding, as the trace element is essential for the development of the foetus and infant. A selenium deficiency during this phase can increase the risk of complications such as pre-eclampsia and premature labour.
• Menopause: During the menopause, a selenium deficiency can exacerbate typical symptoms such as hot flushes, mood swings and sleep disorders. An adequate supply of selenium can help to alleviate these symptoms.
• Thyroid function: Women are more frequently affected by thyroid disorders than men. As selenium is essential for the function of the thyroid gland, a deficiency can increase the risk of thyroid dysfunction.