Supplement Label Index

Copper Amino Acid Chelate vs. Copper Sulfate

Among 3,989 on-market copper products with an identifiable primary form, 33.8% use Copper Amino Acid Chelate (1,347 products) and 8.4% use Copper Sulfate (336).

Copper Amino Acid ChelateCopper Sulfate
Quality tierTier 1Tier 2
Copper by weight30.0%25.4%
Share of market33.8%8.4%
On-market products1,347336
Median declared dose1,000 elemental mcg
middle half: 500–2,000
1,650 elemental mcg
middle half: 900–2,000
Most common brandsDouglas Laboratories, NOW, BluebonnetNature's Way, 21st Century, GNC Women's Ultra Mega

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 Copper Amino Acid Chelate is tier 1

The specific form used in the one human RCT with a defined copper chelate that demonstrated a measurable physiological effect (raised SOD1/ceruloplasmin).

Source: DiSilvestro RA et al. 2012, Metabolism 61(9):1242-6, PMID 22444781

Why Copper Sulfate is tier 2

Used as the reference/comparator form in most animal copper-bioavailability research; highly soluble but not shown superior to organic/chelated forms.

Source: animal comparator evidence, PMID 7883634, not a human RCT

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 copper comparisons