Side by side

Compare supplements

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

Supplement 1Supplement 2Supplement 3

Measure

Add a supplement

Evidence

Moderate evidence

Common protocol200 mg——

Protocols mapped

3 goal-specific

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Timing

30–60 minutes before an acute attention task, or evening in sleep studies

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Expected effect

Within about 1 hour acutely; 2–8 weeks in repeated-dose studies

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Primary uses

AttentionStress researchSleep quality

Watch for

Headache · Drowsiness

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