Selenium Amino Acid Chelate vs. Sodium Selenate
Among 4,693 on-market selenium products with an identifiable primary form, 17.3% use Selenium Amino Acid Chelate (811 products) and 14% use Sodium Selenate (657).
| Selenium Amino Acid Chelate | Sodium Selenate | |
|---|---|---|
| Quality tier | Unrated | Tier 2 |
| Selenium by weight | — | 21.4% |
| Share of market | 17.3% | 14% |
| On-market products | 811 | 657 |
| Median declared dose | 50 elemental mcg middle half: 20–100 | 55 elemental mcg middle half: 20–100 |
| Most common brands | Airborne, Ultima, Douglas Laboratories | 21st Century, Vitamin World, Nature's Way |
Doses are declared per serving in elemental mcg. “By weight” is the share of the ingredient that is the nutrient itself (e.g. elemental magnesium in a magnesium salt).
Why Selenium Amino Acid Chelate is unrated
Terminology inconsistent across manufacturers; composition cannot be determined from the name alone.
Source: none (definitional caveat; no source defines the composition of "selenium amino acid chelate")
Why Sodium Selenate is tier 2
Inorganic selenate is well absorbed but, like selenite, less well retained in tissue than organic selenomethionine, per a general bioavailability review (organic forms show higher retention than inorganic forms); no selenate-specific human study is cited.
Source: Fairweather-Tait SJ et al. 2010, Am J Clin Nutr 91(5):1484S-1491S, PMID 20200264