# item.guide
Side-by-Side Comparison Essential Vitamins & Minerals

Selenium (Elemental Se) vs. Sodium (Elemental Na)

Comparing 2 standards across 11 specifications. 11 key differences identified.

Comparing:
Selenium (Elemental Se)
Sodium (Elemental Na)
Selenium (Elemental Se) →

Selenium is an essential trace element incorporated as Selenocysteine (the 21st amino acid) into 25 human selenoproteins including Glutathione Peroxidases (GPx) and Iodothyronine Deiodinases (T4->T3 conversion). Adult RDA is 55 µg, with a Tolerable Upper Limit of 400 µg/day.

View full Selenium (Elemental Se) spec sheet →
Sodium (Elemental Na) →

Sodium is the principal extracellular cation (135–145 mEq/L extracellular), maintaining extracellular fluid volume, plasma osmolality, and driving secondary active transport. Adequate Intake (AI) is 1,500 mg/day, with a Chronic Disease Risk Reduction (CDRR) limit of 2,300 mg/day.

View full Sodium (Elemental Na) spec sheet →

Specification Comparison Table

11 Parameters
Parameter / Spec
Selenium (Elemental Se)
Sodium (Elemental Na)
Nutrient Type
Essential Trace Element Essential Macromineral / Major Extracellular Electrolyte
Chemical Forms
Selenomethionine (Plant organic), Selenocysteine (Animal selenoprotein), Sodium Selenite / Selenate (Inorganic) Sodium Chloride (NaCl, 39.3% Na by weight), Monosodium Glutamate (MSG, 12.3% Na), Sodium Bicarbonate (27.4% Na)
Primary Biological Function
Glutathione Peroxidase (GPx1-4) lipid hydroperoxide neutralization, Iodothyronine Deiodinases (Converts thyroid T4 into active T3), Thioredoxin Reductase (TXNRD) Extracellular fluid osmolality maintenance, Blood pressure / volume homeostasis, Action potential depolarization (voltage-gated Na+ channels), SGLT1 glucose cotransport
Deficiency Condition
Keshan Disease (Endemic juvenile cardiomyopathy), Kashin-Beck Disease (Deforming osteoarthropathy), Impaired thyroid metabolism Hyponatremia (Serum Na+ < 135 mmol/L): Cerebral edema, Nausea, Muscle cramps, Seizures, Coma (often exercise-associated from over-hydration)
Top Whole Food Sources
Brazil Nuts (1 single nut provides ~70–90µg / 130–160% RDA), Eastern Oysters, Yellowfin Tuna, Halibut, Sardines, Beef Liver, Eggs Table Salt (NaCl), Cured Bacon, Soy Sauce, Parmigiano-Reggiano, Pickles, Olives, Bread (Processed food accounts for 70% of intake)
Adult RDA / RDI
55 µg / day (60 µg pregnancy, 70 µg lactation) —
Tolerable Upper Limit (UL)
400 µg / day (Avoid selenosis / garlic breath, hair/nail brittleness) —
Soil Selenium Geographical Variability
Plant selenium reflects regional soil content; volcanic soils (South America, Great Plains) are rich, while parts of China, Scandinavia, and New Zealand are depleted —
Adult Adequate Intake (AI)
— 1,500 mg / day (Equal to 3.8 g table salt NaCl)
Chronic Disease Limit (CDRR)
— 2,300 mg / day (Equal to 5.8 g table salt / 1 level teaspoon)
Renal Renin-Angiotensin System
— Juxtaglomerular apparatus senses low tubular sodium/pressure, secreting renin to stimulate aldosterone and renal Na+ reabsorption

Other Alternatives to Compare

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