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Compare supplements

Put up to three ingredients next to each other. See where the evidence, dosing, timing, and tradeoffs differ.

Supplement 1Supplement 2Supplement 3

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Evidence

Strong evidence

Common protocol8–18 mg/day total intake for most adults; treatment is clinical——

Protocols mapped

1 goal-specific

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Timing

Empty stomach if tolerated; separate from competing minerals

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Expected effect

Days to months when intake or status is inadequate

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Primary uses

Documented deficiencyIron-deficiency anemiaNutritional adequacy

Watch for

Constipation · Nausea

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