Supplement × Supplement·timing-sensitive·Moderate evidence
Dairy calcium and some protein matrices can reduce non-heme iron absorption when taken together.
Every entry follows the same shape: what is happening, the mechanism, and the recommendation.
What is happening. Dairy calcium and some protein matrices can reduce non-heme iron absorption when taken together.
Mechanism. Mineral absorption competition and meal-matrix effects.
Recommendation. Separate iron supplements from whey or calcium-rich shakes by at least 2 hours when treating deficiency.
Space the doses apart by at least this window to avoid the conflict.
Effect on the composite score
If both Iron and Whey Protein are in the same stack, this pair applies −5 to your Stack Score (per scored timing-sensitive row).
The full algorithm, the clamping rules, and four worked stacks are at /methodology/stack-score.
Every claim on this page is cited. PMIDs link straight to PubMed.
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NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.
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