Selenium-rich Foods - Selenium-rich Diet
Selenium is an essential trace element belonging to the group of micronutrients. This trace element must be obtained daily through diet. Selenium is needed for the formation of certain enzymes (selenoproteins) that have antioxidant effects against free radicals, among other functions. The absorption of selenium in the intestine is relatively high, around 80% 1.
The selenium content of foods strongly depends on soil conditions, that is, the nutrients available to plants during growth 2. In many countries such as Denmark, Finland, and the United Kingdom, the soils are low in selenium, leading to lower selenium concentrations in plants. Therefore, the selenium content in corresponding foods may also vary 3.
Since vegans belong to the risk group for selenium deficiency, the selenium-rich foods mentioned on this page should be consumed regularly. Because with the right selection and consumption of selenium-rich foods, a deficiency can be avoided in healthy individuals. You can find the table of selenium-rich foods here.
We have compiled some selenium-rich foods that should be regularly consumed as part of a healthy diet. These are plant-based or vegan foods with high selenium content.
Selenium is efficiently absorbed by the body. The amino acid selenomethionine (which contains selenium) present in plants is absorbed by the body at more than 90%. 4. Other selenium-rich plants from the Allium and Brassica family, such as garlic and cabbage, can lose up to 89% of their selenium content when boiled in water. Furthermore, plant-based foods also contain selenates and smaller amounts of selenocysteine, which can also be well absorbed.
Selenium Loss Through Processing
Through refining or processing (such as cooking, baking, or grilling), selenium is washed out or destroyed 5 6. Plant-based foods such as mushrooms and asparagus, which are rich in selenium, can lose 40% of their selenium content 7. From this perspective, selenium-rich foods should be eaten as unprocessed as possible or cooked for the shortest time.
Brazil Nuts as the Best Source of Selenium
Some selenium accumulator plants, such as the Brazil nut tree, accumulate high amounts of selenium from the soil. Thus, Brazil nuts, with 1.92 mg per 100 g, are by far the best source of selenium.8. A single Brazil nut contains approximately 70 to 90 µg, which already exceeds the daily selenium requirement for an adult.9. Just two Brazil nuts significantly increase the body's selenium status.10.
The main reason for the high accumulation of selenium in Brazil nuts is that the proteins they contain are high in sulfur-containing amino acids. 11.
Due to the high selenium content, Brazil nuts should be used sparingly to avoid selenium overdose (the daily upper limit is 400 µg). In addition to the high selenium content, it should be noted that Brazil nuts can contain high amounts of barium, which can be toxic. Excessive barium intake can lead to muscle paralysis and potassium deficiency 12.
Other Selenium-rich Nuts and Seeds
Chia seeds contain an exceptionally high selenium content of 55.2 µg per 100 g. Sunflower seeds and cashews are also very selenium-rich, with 53 µg and 19.9 µg respectively. Pistachios contain 7 µg, walnuts 4.9 µg, almonds 4.1 µg, macadamias 3.6 µg, and hazelnuts 2.4 µg of selenium, making them recommended sources. Sesame seeds (34.4 µg) and flaxseed (25 µg) should also not be missing from a balanced and selenium-rich diet.
Legumes are also among the selenium-rich foods. The best sources in this group are soybeans (17.2 µg), red lentils (17 µg), white beans (12.8 µg), and kidney beans (3.2 µg). Peanuts contain 7.2 µg of selenium per 100 g.
In general, grains are very selenium-rich. From a scientific perspective, they are considered non-accumulators of selenium. White rice (15.1 µg), brown rice (7 µg), rye (13.9 µg), and spelt (11.7 µg) all contain selenium. Quinoa and buckwheat, as pseudocereals, also contain some selenium with 8.5 µg and 8.3 µg respectively.
To see which other grains and grain products contain selenium, refer to the table.
Mushrooms with Selenium
Shiitake mushrooms (5.7 µg) and champignons (9.3 µg) should not be missing from a selenium-rich diet. However, cultivated champignons contain less selenium compared to their wild counterparts 13. Most edible mushrooms are low in selenium and contain less than 1 µg of selenium per gram of dry weight 14.
Some wild mushrooms contain higher amounts of selenium. Porcini mushrooms, for example, contain an average of 20 µg of selenium per gram of dry weight (up to 70 µg per gram of dry weight) 15. Other good sources of selenium are pine mushrooms, boletes, summer cep, scaly-stalked bolete, and the attached bolete.
The coconut, classified as a drupe, contains a significant amount of selenium, with 10.1 µg.
Additional foods rich in selenium in this group include bananas (1 µg), mangoes (0.6 µg), persimmons (0.6 µg), lychees (0.6 µg), and papayas (0.6 µg), but they all contribute only minimally to meeting the requirements.
Thus, garlic (14.2 µg), broccoli (2.5 µg), leeks (1 µg), Brussels sprouts (1.6 µg), and kale (0.9 µg) contain higher levels of selenium.
Parsnips (1.8 µg), lamb's lettuce (0.9 µg), asparagus (2.3 µg), spinach (1 µg), and potatoes with skin (0.3 µg) still contain some selenium.
Herbs and Spices
In this group, mustard seeds (ground, 208.1 µg), curry powder (40.3 µg), cumin (12.1 µg), and turmeric (ground, 6.2 µg) stand out as particularly selenium-rich foods. Thyme (4.6 µg), oregano (4.5 µg), marjoram (4.5 µg), and basil (3 µg) also contain higher concentrations of selenium in dried form. Here is the link to selenium content in herbs and spices.
Since grains are selenium-rich, processed products made from these raw materials are also rich in selenium. These include whole wheat spaghetti (36.3 µg) and macaroni (69.4 µg), cooked couscous (27.5 µg), wheat bran (77.6 µg), as well as whole grain breads like pumpernickel (24.5 µg) or whole wheat pita (44 µg). Tofu still contains 17.4 µg of selenium.
Recommended gluten-free selenium-rich foods include amaranth pops, oat flour, oatmeal, and teff flour. According to studies, their selenium content is more than 10 μg per 100 g. 18. In general, products made from oats, amaranth, quinoa, and teff are more valuable sources of selenium compared to products made from traditionally consumed gluten-free grains such as corn, rice, and buckwheat.