wo ist selen enthalten — can a microbiome test help?

Selenium is an essential trace mineral found in Brazil nuts, fish (tuna, sardines), meat (liver, beef), eggs, and mushrooms. Its content in foods varies greatly depending on soil selenium levels. A microbiome test, such as those offered by MyBody-X, analyzes the composition of gut bacteria, not selenium levels. There is no robust scientific evidence that a microbiome test can help assess or improve selenium status. While gut bacteria can influence nutrient absorption, the link to selenium is weak and not clinically actionable. To check selenium status, a blood test (serum or whole blood selenium) ordered by a doctor is appropriate. Caution: selenium supplements can be toxic (selenosis), so never self-supplement without medical guidance. Marketing claims about microbiome tests for mineral status are often exaggerated; the evidence level is best described as marketing.