Can I take copper bisglycinate with zinc?
The short answer
Yes — and in many cases, you should. High-dose zinc supplementation can cause copper deficiency over time. Adding copper bisglycinate offsets this. The key is to separate the two doses by at least 2–4 hours rather than taking them simultaneously, and to keep the zinc-to-copper ratio reasonable.
Why zinc depletes copper
When zinc intake rises, intestinal epithelial cells produce more metallothionein, a metal-binding protein. Metallothionein has a higher binding affinity for copper than for zinc. So as more metallothionein is produced (induced by zinc), it preferentially traps any copper passing through the intestinal lining. The bound copper is then lost when those intestinal cells are sloughed off — a normal process that turns over the gut lining every few days.
The result, over months of high zinc intake, is reduced systemic copper absorption. This mechanism is well documented and has produced clinically significant copper deficiency in case reports — sometimes severe enough to mimic hematologic malignancies before being recognized. Our article on copper and zinc balance covers the evidence in depth.
How much zinc is too much without copper?
Zinc-induced copper deficiency has been reported at chronic intakes above approximately 50 mg/day, but case reports exist at lower habitual intakes when continued for years. The tolerable upper intake level for zinc is 40 mg/day for adults. Many immune-support supplements provide 30–50 mg of zinc, sometimes more. If you take any zinc above the RDA (8–11 mg/day) on an ongoing basis, copper supplementation deserves consideration.
Suggested ratio
A commonly used guideline is a zinc-to-copper ratio of roughly 10:1 to 15:1 when supplementing both. For example, if you take 15 mg of zinc, 1–1.5 mg of copper is reasonable. If you take 30 mg of zinc, 2–3 mg of copper is reasonable. This is rough guidance, not a clinical rule.
Separation in time
Take zinc and copper at different times of day. Common approach: zinc with dinner, copper with breakfast (or vice versa). A 2–4 hour separation is sufficient. Taking them simultaneously is not catastrophic but reduces the absorption of whichever one is in lower concentration.
What about copper-zinc combo supplements?
Some products combine zinc and copper in a single capsule. These are convenient but suboptimal from an absorption standpoint, because they put the two minerals in direct competition at the moment of absorption. They are still better than taking high-dose zinc with no copper at all. If you can split them into separate products taken at different times, do.
Sources
- Duncan et al. (2023). Iatrogenic copper deficiency: Risks and cautions with zinc prescribing. Br J Clin Pharmacol. — bpspubs.onlinelibrary.wiley.com
- Zinc-Induced Copper Deficiency Mimicking Myelodysplastic Syndrome (2025). PMC12334246 — pmc.ncbi.nlm.nih.gov
Related questions
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