Limited evidenceEye health

Cassia Seed (Jue Ming Zi)

Roasted Cassia obtusifolia seeds, brewed as a tea in Chinese medicine for eye strain and constipation. The name literally means 'brighten the eyes', but the eye claim has never been tested clinically, and the seeds carry a real hepatotoxicity concern.

Evidence last reviewed: August 2026

What the science says

Eye strain and vision Limited evidence
A comprehensive review of Cassiae Semen documents its principal traditional indication as clearing the liver and brightening the eyes, but reports no controlled clinical trials for visual or ocular endpoints. The supporting pharmacology is limited to antioxidant and anti-inflammatory activity in laboratory systems.
Laxative effect Limited evidence
The same review describes anthraquinone constituents with documented laxative activity, consistent with the seed's traditional use for constipation. Human dosing and efficacy have not been established in randomised trials.
Hepatotoxicity risk Limited evidence
The review's toxicity section flags anthraquinone-related liver toxicity as the main safety concern with Cassiae Semen, particularly with prolonged or high-dose use. This is the best-characterised risk of the herb and argues against daily long-term consumption.

Dosage & safety

Studied doseNo clinically studied dose. Traditional decoction use is 9–15 g of roasted seeds per day, usually short term; the roasted form is standard and raw seeds are considered harsher.

SafetyAnthraquinones in cassia seed carry a documented hepatotoxicity signal and, like other anthraquinone laxatives, should not be used continuously — avoid long-term daily use and avoid entirely with existing liver disease. Diarrhoea and abdominal cramping are common at higher intakes. Avoid in pregnancy and breastfeeding, in children, and alongside other laxatives or hepatotoxic drugs. It may lower blood pressure, so monitor if taking antihypertensives.

Scientific references

Cassiae Semen: A comprehensive review of botany, traditional use, phytochemistry, pharmacology, toxicity, and quality control
Chen Y, Chen X, Yang X — J Ethnopharmacol, 2023

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