Calcium & Zinc

Caution Absorption Caution Timing
Calcium → Zinc →
Caution Absorption

Calcium may reduce zinc absorption when taken in large doses together.

Mechanism

High-dose calcium can interfere with zinc absorption in the intestine.

Recommendation

Separate calcium and zinc supplements by 2 hours if taking high doses.

Caution Timing

Take calcium and zinc supplements at different times for optimal absorption of both.

Mechanism

High-dose calcium can interfere with zinc absorption in the intestine.

Recommendation

Separate by at least 2 hours if taking high doses of both.

Sources

  • NIH ODS

Drug interaction context

Known drug category interactions for these supplements. Especially relevant if you take prescription medications.

Warning Calcium × Thyroid medication (levothyroxine)

Calcium reduces levothyroxine absorption, potentially causing thyroid levels to fluctuate.

Take levothyroxine at least 4 hours before or after calcium supplements.

Check your full stack including medications →

Tolerable upper intake limits

Reference values for safe daily intake of these supplements.

Calcium
2500.000 mg
adults NIH ODS / IOM

Excess may increase kidney stone risk and potentially cardiovascular risk.

Zinc
40.000 mg
adults NIH ODS / IOM

Chronic high intake can cause copper deficiency and immune dysfunction.

All interactions Check your stack
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Medical Disclaimer: Noyemi provides information from published research for educational purposes only. This content is not medical advice and does not replace consultation with a qualified healthcare provider. Always consult your doctor before starting, stopping, or changing any supplement regimen, especially if you take medications or have existing health conditions.