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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 protocol150 mcg/day total intake for adults——

Protocols mapped

1 goal-specific

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Timing

With food

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Expected effect

Days to months when intake or status is inadequate

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Primary uses

Nutritional adequacyDeficiency preventionThyroid-hormone synthesis

Watch for

Thyroid dysfunction with excess · Metallic taste or gastrointestinal upset

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