What is selenium?
Selenium is an essential trace element, present in small quantities in the body, but essential for the proper functioning of the immune system, thyroid and antioxidant defenses.
This powerful antioxidant plays a major role in protecting cells against oxidative stress, helping to prevent premature aging and chronic disease. It is found naturally in foods such as Brazil nuts, seafood and whole grains, as well as in dietary supplements.
What are the benefits of selenium?
Selenium is a key element for overall health and has many protective effects:
Strengthens the immune system → Stimulates natural defenses and helps the body fight viral and bacterial infections.
Protects cells against oxidative stress → Neutralizes free radicals, preventing skin aging and degenerative diseases.
Supports healthy thyroid function → Essential for thyroid hormone production, preventing hormonal and metabolic disorders.
Improves male fertility → Promotes sperm production and mobility, reducing the risk of infertility.
Preserves cardiovascular health → Protects blood vessels and reduces the risk of heart disease.
Stimulates hair and nail growth and quality → Helps prevent hair loss and brittle nails.
Reduces the risk of certain cancers → Its protective effect on DNA limits the development of cancer cells.
How to use selenium
Selenium can be supplied to the body in two main ways: through the diet and via dietary supplements.
Natural sources of selenium
Certain foods are particularly rich in bioavailable selenium:
Brazil nuts → One of the richest foods in selenium (just one nut covers daily requirements).
Seafood and fish → Tuna, sardines, shrimp and oysters.
Meat and offal → Turkey, liver, kidneys.
Eggs and dairy products → Natural sources suitable for varied diets.
Pulses and wholegrain cereals → Lentils, chickpeas, quinoa and brown rice.
As a dietary supplement
Selenium is available in several forms:
Recommended dosage
The recommended daily allowance (RDA) for selenium is approx:
It is important not to exceed 400 µg per day, as excess can have undesirable effects.
Does selenium improve skin and hair health?
Yes, thanks to its antioxidant properties, selenium is an asset for beauty and vitality:
Protects skin against premature aging → Reduces the impact of UV rays, pollution and oxidative stress.
Strengthens hair fiber → Limits hair loss and promotes hair growth.
Prevents nail fragility → Helps strengthen brittle and split nails.
It is often incorporated into hair, skin and nail supplement formulas, in combination with zinc, biotin and B-group vitamins.
Is selenium beneficial for fertility and reproduction?
Yes, selenium plays a key role in male reproductive health:
Is selenium effective in preventing cardiovascular disease?
Yes, it helps protect the heart and blood vessels by :
Reducing inflammation and oxidative stress, which are risk factors for cardiovascular disease.
Preventing the build-up of bad cholesterol (LDL) and protecting arteries.
Improves blood circulation, reducing the risk of hypertension and thrombosis.
It is often recommended in combination with omega-3 and vitamin E for optimum cardiovascular protection.
Where can I buy quality selenium?
Selenium is available in :
Pharmacies and parapharmacies → In the form of dietary supplements and capsules.
Organic and health food stores → Present in natural and organic formulations.
Nutraceutical specialty stores → In the form of highly bioavailable selenomethionine.
Grocery stores and supermarkets → In foods naturally rich in selenium (Brazil nuts, fish, wholegrain cereals).
It's advisable to choose certified, additive-free supplements for best absorption and optimal efficacy.
Does selenium have any contraindications or side effects?
Although beneficial, selenium must be taken with care:
Too much can cause intoxication (selenosis) → Symptoms: hair loss, digestive disorders, fatigue and garlic-smelling breath.
Not recommended in cases of hyperthyroidism, as it influences thyroid hormone production.
Interaction with certain drugs → In particular anticoagulants and thyroid treatments.
Avoid in cases of autoimmune disease, except on medical advice.
Moderate dosage and a balanced diet are generally sufficient to avoid deficiencies without risk of overdosing.
