Supplement analysis backed by scientific evidence · PT

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Limited evidenceJoints & skin

Achyranthes (Niu Xi)

A root used in Chinese formulas for the knees and lower back, almost always as one component of a multi-herb prescription. Nearly all published research is in animals and cells; there are no placebo-controlled human trials of the herb on its own.

Evidence last reviewed: August 2026

What the science says

  • Bone loss in animal models Limited evidence

    A systematic review and meta-analysis of preclinical studies found that Achyranthes bidentata root extract improved bone density and structural parameters in osteoporotic rats. The finding is consistent across rodent studies but has not been tested in people.

  • Joint and back complaints Limited evidence

    A comprehensive pharmacology review describes anti-inflammatory, analgesic and osteoprotective activity in laboratory models and long traditional use for knee and lumbar pain. The same review notes the absence of well-designed clinical trials of the single herb.

  • Isolated use versus traditional formulas Limited evidence

    In practice the herb is used inside multi-ingredient prescriptions, so even the clinical impressions behind its reputation cannot be attributed to Achyranthes specifically.

Dosage & safety

Studied doseTraditional decoctions use 9–15 g of the dried root per day. Supplement extracts vary widely in concentration and no dose has been established in trials.
SafetyTraditionally contraindicated in pregnancy because of reported uterine-stimulating activity, and generally avoided with heavy menstrual bleeding. Human safety data are sparse. As with other imported herbal materials, check for third-party testing for heavy metals and adulteration. Not a substitute for assessment of persistent joint or back pain.

Scientific references

Where to buy

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