Selenium-rich foods: what they contain and why selenium matters
Selenium is an essential trace element incorporated as selenocysteine into 25 known human selenoproteins that regulate cellular redox balance and thyroid hormone deiodination [WHO]. Selenoproteins, including glutathione peroxidases and thioredoxin reductases, serve structural and enzymatic functions in neutralizing reactive oxygen species [WHO]. Reference daily requirements established by dietary authorities are calibrated to achieve maximum activity of plasma glutathione peroxidase [ICMR-NIN].
Last reviewed: 2026-09-05
How much selenium is in common foods
Values represent micrograms (µg) of selenium per 100 g edible portion.
| Food | Selenium per 100 g | Source |
|---|---|---|
| Brazil nuts (dried, unblanched) | 1917 µg | USDA |
| Pork kidney (cooked, braised) | 311 µg | USDA |
| Eastern oysters (cooked, moist heat) | 154 µg | USDA |
| Beef kidney (cooked, simmered) | 141 µg | USDA |
| Yellowfin tuna (cooked, dry heat) | 108 µg | USDA |
| Wheat bran (crude) | 77.6 µg | USDA |
| Egg yolk (raw) | 56 µg | USDA |
| Halibut (cooked, dry heat) | 55.4 µg | USDA |
| Sunflower seed kernels (dried) | 53 µg | USDA |
| Atlantic sardines (canned in oil, drained solids) | 52.7 µg | USDA |
| Shrimp (cooked, moist heat) | 49.5 µg | USDA |
| Pink salmon (cooked, dry heat) | 46.8 µg | USDA |
| Pork chop (loin) (cooked, broiled) | 44.6 µg | USDA |
| Whole wheat flour (raw) | 42.5 µg | USDA |
| Beef liver (cooked, braised) | 36.1 µg | USDA |
| Chicken breast (cooked, roasted) | 31.9 µg | USDA |
| Chicken egg (whole, raw) | 30.7 µg | USDA |
| Turkey breast (cooked, roasted) | 29.7 µg | USDA |
| Shiitake mushrooms (dried) | 24.8 µg | USDA |
| Brown rice (medium grain, raw) | 15.1 µg | USDA |
| Portobello mushrooms (grilled) | 13 µg | USDA |
| White button mushrooms (stir-fried) | 11.5 µg | USDA |
| Bengal gram (Chickpeas) (whole, dry) | 8.9 µg | ICMR-NIN |
| Lentils (mature seeds, raw) | 8.2 µg | USDA |
| Black gram (Urad) (whole, dry) | 7.2 µg | ICMR-NIN |
| Red gram (Tur/Pigeon pea) (split, dry) | 6.8 µg | ICMR-NIN |
| Green gram (Moong) (whole, dry) | 5.5 µg | ICMR-NIN |
| Pearl millet (Bajra) (whole grain, raw) | 5.2 µg | ICMR-NIN |
| Finger millet (Ragi) (whole grain, raw) | 4.8 µg | ICMR-NIN |
Selenium and your blood test
Serum selenium is measured only in particular clinical situations. If you have a lab report, ReadMyReport explains what your selenium result means for you.
Frequently asked questions
- Why does the selenium content of plant foods vary substantially?
- Plants absorb selenium from the soil in the form of inorganic selenate or selenite; therefore, the selenium concentration in grains, pulses, and vegetables directly reflects the geological selenium levels and soil pH of the cultivation region [WHO].
- How does selenium concentration differ between egg yolk and egg white?
- Selenium concentrates preferentially in the lipid and protein fractions of the yolk, with whole egg containing 30.7 µg per 100 g, raw egg yolk containing 56.0 µg per 100 g, and raw egg white containing 20.0 µg per 100 g [USDA].
- What chemical forms of selenium are found in food sources?
- Plant foods primarily provide organic selenomethionine, which is non-specifically incorporated into general body proteins in place of methionine, whereas animal tissues supply both selenocysteine and selenoproteins [WHO].
- Why do Brazil nuts contain exceptionally high concentrations of selenium?
- The Brazil nut tree (Bertholletia excelsa) is a recognized selenium hyperaccumulator whose extensive root system extracts selenium from South American soils, resulting in an average tissue concentration of 1917 µg per 100 g [USDA].
- What role does selenium play in thyroid hormone metabolism?
- Selenium is an obligate structural component of the three iodothyronine deiodinase enzymes (types I, II, and III), which catalyze the removal of iodine atoms to convert thyroxine (T4) into biologically active triiodothyronine (T3) or inactive metabolites [WHO].
- Does cooking alter the selenium content of foods?
- Selenium compounds are relatively heat-stable during routine baking and boiling, but cooking in large volumes of water can cause minor reductions through leaching of soluble selenium compounds into the cooking liquid [ICMR-NIN].
Sources
- USDA FoodData Central — USDA FoodData Central, Agricultural Research Service. https://fdc.nal.usda.gov/
- ICMR-NIN — Indian Food Composition Tables 2017, National Institute of Nutrition. https://www.nin.res.in/
- NIH ODS — NIH Office of Dietary Supplements — Selenium, Fact Sheet. https://ods.od.nih.gov/