# Selenium Iodide **Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/selenium-iodide **Data Source:** Hermetica Superfoods Ingredient Encyclopedia **Updated:** 2026-04-04 **Evidence Score:** 2 / 10 **Category:** Mineral **Also Known As:** SeI₂, selenium diiodide, selenium(II) iodide, diselenium diiodide, selenium-iodine compound ## Overview Selenium iodide (SeI2 or related selenium-iodine compounds) is an inorganic chemical compound studied primarily in materials science and synthetic chemistry, not as a dietary supplement or therapeutic agent. It has no established biological role, no documented bioavailability data in humans, and no recognized nutritional or pharmacological application. ## Health Benefits • No documented health benefits - selenium iodide has no evidence of use as a supplement or clinical agent • No human trials exist - all references pertain to materials science or basic chemistry • No biomedical applications - lacks any biological activity data • No nutritional value established - selenium and iodine are handled separately in nutrition • No therapeutic uses identified - absent from all biomedical contexts ## Mechanism of Action No mechanism of action has been established for selenium iodide in any biological system. Unlike selenomethionine or selenocysteine, which are incorporated into selenoproteins such as [glutathione](/ingredients/condition/detox) peroxidase (GPx) and thioredoxin reductase (TrxR) via the UGA codon pathway, selenium iodide has not been shown to interact with any mammalian enzyme, receptor, or transport protein. Its chemical reactivity is studied in the context of inorganic synthesis and semiconductor materials, not cellular redox biology. ## Clinical Summary No clinical trials, animal studies, or controlled in vitro investigations have been conducted on selenium iodide as a biomedical or nutritional agent. A search of PubMed, ClinicalTrials.gov, and major pharmacological databases returns no human or animal studies examining its safety, efficacy, or bioavailability. All scientific literature referencing selenium iodide pertains exclusively to materials science, crystal chemistry, or inorganic synthesis contexts. The evidence base for any health claim is entirely absent, making it impossible to draw conclusions about therapeutic potential. ## Nutritional Profile Selenium iodide (SeI) is an inorganic compound composed of selenium (Se) and iodine (I), classified as a mineral/chemical compound rather than a nutritional substance. It is not found in food supplies, dietary supplements, or pharmacopeias. Key details: • Molecular composition: Se and I in a binary compound (various stoichiometries reported, e.g., Se₂I₂, SeI₄, SeI₂) — none are approved for human consumption. • Elemental selenium content: approximately 28–44% by mass depending on stoichiometry (e.g., SeI₂ ≈ 24.1% Se by mass; Se₂I₂ ≈ 38.3% Se by mass). • Elemental iodine content: approximately 56–76% by mass depending on stoichiometry. • Bioavailability: Not established — no data exist on gastrointestinal absorption, [metabolism](/ingredients/condition/weight-management), or tissue distribution of selenium iodide as a compound in humans or animals. • No macronutrient value (0 g protein, 0 g carbohydrate, 0 g fat, 0 g fiber, 0 kcal). • No vitamins or bioactive organic compounds present. • Although selenium and iodine are individually essential trace minerals (RDA for Se: 55 µg/day; RDA for I: 150 µg/day in adults), selenium iodide as a compound is NOT a recognized or safe source of either nutrient. • Potential toxicity concern: Both selenium and iodine are toxic at elevated doses (Se UL: 400 µg/day; I UL: 1,100 µg/day), and the uncontrolled release of both elements simultaneously from an uncharacterized inorganic salt poses significant safety risks. • No GRAS (Generally Recognized as Safe) status, no monograph in any pharmacopeia (USP, EP, BP), and no listing in any national or international food composition database (USDA, EFSA, Codex Alimentarius). • All known references to selenium iodide pertain to materials science, semiconductor research, and inorganic chemistry — not nutrition or biomedicine. ## Dosage & Preparation No clinically studied dosage ranges exist for any form of selenium iodide, as it lacks biomedical applications or standardization in studies. Consult a healthcare provider before starting any new supplement. ## Safety & Drug Interactions The safety profile of selenium iodide as an ingested or applied substance has not been evaluated in humans or animals under controlled conditions. General toxicology of inorganic selenium compounds suggests potential for selenium toxicity (selenosis) at elevated exposures, presenting as hair loss, nail brittleness, gastrointestinal distress, and neurological symptoms. Similarly, excess iodine from inorganic sources can disrupt [thyroid function](/ingredients/condition/hormonal), causing hypothyroidism or hyperthyroidism, particularly in sensitive populations. Pregnancy safety, drug interaction data, and contraindication profiles are entirely undocumented; use during pregnancy or alongside thyroid medications or anticoagulants would carry unquantified risk. ## Scientific Research No human clinical trials, RCTs, or meta-analyses exist for selenium iodide as a biomedical ingredient. PubMed searches yield no biomedical studies, with all available references pertaining only to materials science or basic chemistry applications. ## Historical & Cultural Context No historical or traditional medicinal uses are recorded for selenium iodide in any traditional medicine systems including Ayurveda or TCM. While selenium and iodine have separate traditional roles, they have never been used as a combined mineral form. ## Synergistic Combinations Not applicable - no biomedical use established ## Frequently Asked Questions ### Is selenium iodide safe to take as a supplement? Selenium iodide has never been evaluated for safety as a dietary supplement in humans or animals. Because it is an inorganic compound with no established bioavailability or toxicological profile, its ingestion carries unquantified risk of both selenium and iodine toxicity, including selenosis and thyroid disruption. It is not recommended for supplemental use under any circumstances. ### What is selenium iodide used for? Selenium iodide is used exclusively in materials science and inorganic chemistry contexts, such as the synthesis of semiconductor compounds and crystallographic research. It has no documented use in medicine, nutrition, or dietary supplementation. Any products claiming to contain selenium iodide for health purposes lack scientific substantiation. ### How is selenium iodide different from other selenium supplements like selenomethionine? Selenomethionine is an organic selenium compound naturally incorporated into proteins via methionine pathways and is the most bioavailable form of supplemental selenium, supporting glutathione peroxidase and thioredoxin reductase activity. Selenium iodide, by contrast, is an inorganic selenium-iodine compound with no known absorption pathway, no selenoprotein integration data, and no demonstrated biological activity in humans or animals. ### Does selenium iodide have any health benefits? No health benefits have been documented for selenium iodide in any peer-reviewed human, animal, or in vitro study. Unlike biologically active selenium forms such as selenocysteine or sodium selenite, selenium iodide has no recorded interaction with antioxidant enzymes, immune pathways, or thyroid metabolism. Any health claims associated with this compound are unsupported by scientific evidence. ### Can selenium iodide affect thyroid function? While both selenium and iodine individually play critical roles in thyroid hormone synthesis — selenium supporting deiodinase enzymes (DIO1, DIO2) and iodine being incorporated into thyroxine (T4) and triiodothyronine (T3) — selenium iodide as a combined compound has never been studied in relation to thyroid physiology. Its inorganic nature raises theoretical concern for thyroid disruption from excess iodine, but no empirical data exists to confirm or quantify this effect. ### Why is selenium iodide not commonly found in supplement formulations? Selenium iodide lacks established clinical evidence and has never been studied in human trials, making it unsuitable for supplement development. The supplement industry typically uses well-researched forms like selenomethionine or sodium selenite, which have documented absorption and safety profiles. Additionally, selenium and iodine are regulated and dosed separately in nutritional supplements based on distinct physiological roles. ### What is the difference between selenium iodide and naturally occurring selenium and iodine compounds in food? Selenium iodide is a synthetic chemical compound with no identified nutritional or biological function, whereas selenium and iodine occur naturally in foods as separate, bioavailable compounds with well-established roles in human health. Foods provide organic forms of selenium (like selenomethionine in grains) and inorganic iodine (from iodized salt and seafood) that the body can readily utilize. Selenium iodide has not been evaluated for safety or efficacy as a food component or supplement. ### Is there any scientific research supporting the use of selenium iodide in humans? No human clinical trials or biomedical research exists demonstrating any therapeutic use or safety profile for selenium iodide as a supplement or treatment. Available references to selenium iodide are limited to materials science and basic chemistry literature with no relevance to human health or nutrition. Without evidence of biological activity or health benefits, selenium iodide cannot be recommended as a supplement ingredient. --- *Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com* *License: CC BY-NC-SA 4.0 — Attribution required. Commercial use: admin@hermeticasuperfoods.com*