Is copper glycinate the same as copper bisglycinate?
The short answer
In nearly all supplement contexts, the two terms refer to the same compound: a copper ion chelated to two glycine molecules. "Bisglycinate" is the more precise term — "bis" means "two" — but most products labeled "copper glycinate" are functionally identical to those labeled "copper bisglycinate."
The naming convention
Strictly speaking, there are two possible chelate compounds:
- Copper monoglycinate — a 1:1 copper-to-glycine ratio. Less stable, rarely used in commercial supplements.
- Copper bisglycinate — a 1:2 copper-to-glycine ratio. The form used in virtually all reputable supplements. "Bisglycinate" or "diglycinate" both refer to this form.
When a product is labeled simply "copper glycinate," it is almost always the bisglycinate form in practice. Supplement manufacturers use the terms interchangeably, and the FDA does not require strict differentiation in product labeling.
How to verify what you are actually buying
If you want to confirm a product is the 1:2 chelated form, check the Supplement Facts panel for one of these specific listings:
- Copper bisglycinate
- Copper diglycinate
- TRAACS® Copper Bisglycinate Chelate (the branded, patented form from Balchem)
- Albion® Copper Bisglycinate (older naming, same manufacturer)
A product labeled only "copper glycinate" is most likely the bisglycinate form, but you cannot verify it from the label alone. If precision matters to you, look for one of the more specific designations.
Does the distinction matter clinically?
Probably not. In practice, the supplement market has standardized around the 1:2 chelate form. The clinical difference between a hypothetical "1:1 copper glycinate" and a "1:2 copper bisglycinate" has not been characterized in human trials, because the 1:1 form is rare in commercial supplements.
Sources
- NIH Office of Dietary Supplements — Copper Fact Sheet for Health Professionals — ods.od.nih.gov
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