From the Guidelines
Taking a 30 mg zinc picolinate supplement daily can potentially cause a copper deficiency over time, as high zinc intake can reduce copper absorption, and it is recommended to maintain a ratio of 8- to 15-mg zinc to 1-mg copper to avoid zinc-induced copper deficiency. This is based on the guidelines from the British Obesity and Metabolic Surgery Society, which suggest that zinc and copper have an inverse relationship for absorption, and high zinc intake can lead to copper deficiency 1. The guidelines recommend starting with 30 mg d−1 zinc after BPD/DS, but also emphasize the importance of monitoring both zinc and copper levels to avoid zinc-induced copper deficiency.
Some key points to consider:
- Zinc and copper compete for absorption in the intestines, and high zinc intake can reduce copper absorption 1.
- For most adults, zinc intake should not exceed 40 mg daily from all sources (including supplements and diet) to avoid adverse effects such as copper deficiency 1.
- If you need to take zinc supplements long-term, consider periodic monitoring of copper levels, especially after 2-3 months of supplementation, and maintain a ratio of 8- to 15-mg zinc to 1-mg copper 1.
- You might also benefit from taking a multivitamin/mineral supplement that contains copper (about 2 mg) or ensuring your diet includes copper-rich foods like shellfish, nuts, seeds, and dark chocolate.
- Early signs of copper deficiency include fatigue, weakened immune function, anemia, and neurological symptoms, and if you experience these symptoms while taking zinc supplements, consult your healthcare provider for evaluation 1.
From the Research
Zinc Supplementation and Copper Deficiency
- Daily supplementation with 30 milligrams of zinc picolinate (Zn) may lead to copper (Cu) deficiency, specifically hypocupremia, as high intakes of zinc relative to copper can cause copper deficiency 2, 3.
- Studies have shown that excessive zinc intake can induce copper deficiency, characterized by anemia, neutropenia, and impaired immune function 2, 4, 5.
- The risk of copper deficiency is particularly high when zinc supplements are taken in high doses, as this can block the intestinal absorption of copper 4, 6.
- Copper deficiency can cause a range of symptoms, including anemia, neutropenia, and neurological symptoms, which may be misdiagnosed or attributed to other conditions 6.
- It is essential to be aware of the potential risk of copper deficiency when taking zinc supplements, particularly at high doses, and to monitor plasma copper levels to prevent iatrogenic copper deficiency 6.