Why they compete
Zinc and copper share absorption transporters in the intestine. Excess zinc reduces copper absorption; excess copper reduces zinc absorption. The relationship is competitive.
Optimal ratio
- Zinc/copper ratio: 0.7-1.5
- Plasma zinc: 80-120 µg/dL
- Plasma copper: 90-150 µg/dL
Zinc functions
- Immune function (T-cell development, antiviral)
- Testosterone synthesis (cofactor)
- Wound healing
- Taste and smell
- DNA synthesis
- Insulin function
Copper functions
- Connective tissue (collagen crosslinking)
- Iron metabolism
- Neurotransmitter synthesis
- Antioxidant function (SOD)
- Energy production (cytochrome c)
Supplementation strategy
- Zinc: 15-30 mg daily; pair with copper if supplementing long-term
- Copper: 1-2 mg daily if pairing with zinc >30 mg
- Avoid zinc supplementation without copper if doing so chronically
- Test ratio before deciding to supplement
The clinical pearl: Don't supplement high-dose zinc without copper consideration. Test the ratio first.
Bottom line
Zinc and copper compete and balance. Ratio matters. Test before supplementing. Avoid imbalance from chronic single-mineral supplementation.
0.7-1.5
optimal zinc/copper ratio
Compete
for absorption
Both
essential trace minerals