Selenium supports antioxidant defenses (glutathione peroxidases), thyroid function (deiodinases), and immunity. Content varies greatly depending on soil geographical origin. For guidelines and safety, see the ODS professional fact sheet.
Top 15 — selenium-rich foods
Indicative guidelines (µg/100 g or per serving); strong variations depending on soil/species/farming/product. For precise values, use the Ciqual table and FoodData Central.
- Brazil nuts: very rich, extreme variability (a few nuts can cover > 100% of the guideline)
- Tuna/mackerel/sardines/herring: ~30–90 µg/100 g
- Liver/kidneys: ~40–120 µg/100 g
- Shrimp/crab/oysters: ~30–70 µg/100 g
- Pork/beef/chicken: ~15–40 µg/100 g
- Eggs: ~10–30 µg/100 g (≈ 6–15 µg/egg)
- Cheese: ~5–20 µg/100 g
- Whole wheat bread/fortified cereals: variable (check label)
- Sunflower/sesame seeds: ~20–50 µg/100 g
- Brown rice/oats: ~10–20 µg/100 g
- Mushrooms: ~5–20 µg/100 g
- Lentils/chickpeas (cooked): ~2–6 µg/100 g
- Walnuts/hazelnuts/almonds: ~2–6 µg/100 g (excluding Brazil nuts)
- Dairy products: ~2–8 µg/100 g
- Mineral waters (some): may contain selenium (traces to modest)
Variability is major: alternate fish, eggs, meat/offal, and grains/seeds. Brazil nuts are very concentrated: 1–2 nuts often suffice as an occasional boost.
Optimizing absorption
- Vary sources to smooth out geographical variability of selenium.
- Moderate cooking: avoid prolonged overcooking.
- Fortified products: useful in case of low intakes (cereals/beverages).
- Iodine and thyroid: balance with other trace elements (e.g., iodine) participates in thyroid function.
Daily guidelines (recommended intakes)
Usual guidelines: ≈ 55–70 µg/day for adults (references differ by organization). See the ODS professional synthesis and European reference values.
| Population | Daily guideline |
|---|---|
| Adults | ≈ 55–70 µg/day |
| Pregnancy | ≈ 60–70 µg/day |
| Breastfeeding | ≈ 70–85 µg/day |
Risks, interactions and precautions
- Selenosis (excess): brittle nails/hair, gastrointestinal disorders, garlic breath; usual UL ≈ 400 µg/day (international references; some differences exist between organizations). See ODS safety section.
- Brazil nut variability: highly fluctuating content; moderate consumption frequency.
- Interactions: caution if multi-mineral supplementation (balances with iodine, zinc, copper).
Avoid high-dose self-medication. Prioritize a varied diet; adjust intakes with a professional in case of thyroid disease, pregnancy, or long-term supplementation.
Sources and further reading
- Mechanisms, needs, safety: ODS professional fact sheet – Selenium.
- Composition tables: Ciqual table (ANSES), FoodData Central (USDA).
