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Herbal Extract

Polygala Tenuifolia

A traditional herb used in Chinese medicine to support memory, mood, and cognitive clarity.

Evidence gradeCross-checked · Moderate
B
WeakModerateStrong
3.7/ 5 rating

KÖGN Health grades Polygala Tenuifolia as B (Moderate evidence) and rates it 3.7 out of 5.

Last reviewed · June 2026

CategoryNatural · Herbal Extract
Typical doseThere is no well-established standalone human dose; it is traditionally used in decoctions and combination formulas, and extract potency varies widely.
AvailabilityOTC

Primary effects

  • Improved memory
  • Mood support
  • Cognitive clarity

How it works

Modulates neurotransmitter systems associated with memory and emotional balance.

Overview

Polygala Tenuifolia has a long history of use in traditional medicine for cognitive and emotional support. Modern research suggests it may influence neurotransmitter systems related to learning and mood regulation. However, human clinical evidence is still limited, and its effects are considered mild and gradual.

The evidence

Polygala tenuifolia (yuan zhi) is a traditional Chinese herb used for memory and calm. Preclinical studies are interesting — its saponins raise neurotrophins (BDNF, NGF) and protect neurons — but robust human trials are scarce, and most evidence is from animals or traditional combination formulas. Promising mechanistically, largely unproven in people.

How to dose it

There is no well-established standalone human dose; it is traditionally used in decoctions and combination formulas, and extract potency varies widely.

When to take it

Chronic — traditional use is sustained.

Safety & side effects

Can irritate the stomach and cause nausea, partly due to its saponins; quality and identity of products vary.

Who should avoid it

Use care with stomach ulcers or gastritis (it is a GI irritant) and in pregnancy (it can stimulate the uterus). Choose tested products and discuss with a clinician; the human evidence is thin.

References

Related ingredients

Graded entries that target the same cognitive goals.

Categories

Natural NootropicsMemory & LearningMood & Emotional RegulationSerotonergics (Serotonin Support)Long-Term Cognitive SupportOver-the-Counter (OTC)Moderate Evidence

Draft — the dose, safety and evidence notes on this entry were prepared from the published literature and are pending editorial and clinical review.

Educational information, not medical advice. The evidence grade is KÖGN’s editorial assessment of published research, not a health claim. Speak to a qualified clinician before changing what you take.