Supplement Label Index

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 ChelateSodium Selenate
Quality tierUnratedTier 2
Selenium by weight21.4%
Share of market17.3%14%
On-market products811657
Median declared dose50 elemental mcg
middle half: 20–100
55 elemental mcg
middle half: 20–100
Most common brandsAirborne, Ultima, Douglas Laboratories21st 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; needs manual review to determine actual composition.

Source: uncertain -- needs review

Why Sodium Selenate is tier 2

Inorganic selenate is well absorbed but, like selenite, less well retained in tissue than organic selenomethionine per general bioavailability literature.

Source: uncertain -- needs review for a direct comparative citation

Tiers summarize published comparative bioavailability or outcome evidence for each form (see methodology). This page describes the market; it is not a recommendation to take either form. Talk to a clinician about what's right for you.

Other selenium comparisons