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Can You Take Calcium Citrate and Iron Together?
May affect absorption
The short answer
Calcium (as Calcium Citrate) competes with iron for DMT1 transporter absorption. Co-administration may reduce iron uptake by 30-50%.
How to arrange timing
Consider separating this calcium form and iron by at least 2 hours for optimal absorption.
Reference
Reference noted for this combination: NIH ODS Iron Fact Sheet; Hallberg L, Am J Clin Nutr 1991
Important context
Whether supplements suit you together also depends on dose, product formulation, health conditions, and medication use. Ask a doctor or pharmacist first if you take medication, are pregnant or breastfeeding, or have a chronic condition.