Supplement Label Index

Iron Amino Acid Chelate vs. Ferrous Gluconate

Among 1,931 on-market iron products with an identifiable primary form, 8.6% use Iron Amino Acid Chelate (167 products) and 7.1% use Ferrous Gluconate (138).

Iron Amino Acid ChelateFerrous Gluconate
Quality tierTier 1Unrated
Iron by weight11.6%
Share of market8.6%7.1%
On-market products167138
Median declared dose10 elemental mg
middle half: 5–18
9 elemental mg
middle half: 3–17.25
Most common brandsNaturesPlus, Douglas Laboratories, MH Michael's Health Naturopathic ProgramsWonder Laboratories, DC, ALLMAX

Doses are declared per serving in elemental mg. “By weight” is the share of the ingredient that is the nutrient itself (e.g. elemental magnesium in a magnesium salt).

Why Iron Amino Acid Chelate is tier 1

If equivalent to ferrous bisglycinate chelate, showed substantially higher apparent bioavailability than ferrous sulfate.

Source: Pineda O, Ashmead HD. 2001, Nutrition 17(5):381-384, PMID 11377130

Why Ferrous Gluconate is unrated

Commonly used clinically as a milder-tolerated alternative to sulfate, but no comparative human bioavailability citation was independently verified.

Source: uncertain -- needs review

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 iron comparisons