Research
Micronutrients & recovery
Calcium supplementation does not negatively impact long-term iron status, despite short-term studies showing reduced iron absorption.
You can take calcium supplements without worrying about causing iron deficiency, even if you take them with meals. Long-term studies show that calcium does not harm your iron status, despite some short-term studies showing reduced absorption in a single meal.
GoodRefutesHIGH confidence
In contrast, the negative effect of calcium on iron absorption has not been confirmed in long-term supplementation studies.
Why this rating
Supported by multiple long-term studies showing no negative effect on iron status.
Source
Micronutrient interactions: effects on absorption and bioavailability
Brittmarie Sandström · British Journal Of Nutrition · 2001
DOI 10.1079/bjn2000312
narrative_reviewCited 356×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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