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

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Evidence

Moderate evidence

Common protocol1,500 mg/day crystalline glucosamine sulfate——

Protocols mapped

1 goal-specific

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Timing

Once daily with food if needed for tolerance

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Expected effect

8–12 weeks; some structure studies lasted years

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Primary uses

Knee osteoarthritis researchJoint painPhysical function

Watch for

Nausea · Heartburn

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