Selenium (Elemental Se) vs. Vitamin C (L-Ascorbic Acid)
Comparing 2 standards across 9 specifications. 9 key differences identified.
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.
Vitamin C is a water-soluble electron donor and antioxidant essential for collagen proline/lysine hydroxylation, non-heme iron absorption, and immune phagocyte function. Adult RDA is 90mg (men) / 75mg (women), with a Tolerable Upper Limit of 2,000mg/day.
Specification Comparison Table
9 Parameters| Parameter / Spec | ||
|---|---|---|
|
Nutrient Type
|
Essential Trace Element | Water-Soluble Vitamin |
|
Adult RDA / RDI
|
55 µg / day (60 µg pregnancy, 70 µg lactation) | 90 mg (Men) / 75 mg (Women) (+35mg for smokers) |
|
Tolerable Upper Limit (UL)
|
400 µg / day (Avoid selenosis / garlic breath, hair/nail brittleness) | 2,000 mg / day (Avoid osmotic diarrhea) |
|
Chemical Forms
|
Selenomethionine (Plant organic), Selenocysteine (Animal selenoprotein), Sodium Selenite / Selenate (Inorganic) | L-Ascorbic Acid, Sodium Ascorbate, Calcium Ascorbate |
|
Primary Biological Function
|
Glutathione Peroxidase (GPx1-4) lipid hydroperoxide neutralization, Iodothyronine Deiodinases (Converts thyroid T4 into active T3), Thioredoxin Reductase (TXNRD) | Prolyl/Lysyl Hydroxylase cofactor (Collagen), ROS scavenger, Carnitine synthesis |
|
Deficiency Condition
|
Keshan Disease (Endemic juvenile cardiomyopathy), Kashin-Beck Disease (Deforming osteoarthropathy), Impaired thyroid metabolism | Scurvy (Collagen breakdown, capillary fragility, impaired wound healing) |
|
Top Whole Food Sources
|
Brazil Nuts (1 single nut provides ~70–90µg / 130–160% RDA), Eastern Oysters, Yellowfin Tuna, Halibut, Sardines, Beef Liver, Eggs | Red Bell Pepper, Strawberries, Citrus, Kiwi, Broccoli, Brussels Sprouts |
|
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 | — |
|
Thermolability
|
— | Highly heat- and oxygen-sensitive (degrades rapidly with prolonged boiling) |