Typical dose

Oral: 100-500 mg of standardized extract (typica...

Oral Oral safety: very low

About this supplement

Polygonum cuspidatum extract is derived from the root of Japanese knotweed, a perennial plant native to East Asia. It is primarily standardized for its high content of resveratrol (a stilbenoid polyphenol), along with other bioactive compounds including emodin, polydatin (resveratrol glucoside), and anthraquinones. The extract is widely used in dietary supplements for its antioxidant, anti-inflammatory, and potential cardioprotective properties. In topical applications, it is valued for skin anti-aging, brightening, and photoprotection due to its ability to inhibit collagen degradation and reduce hyperpigmentation.

How much to take

Typical amount
Oral: 100-500 mg of standardized extract (typically providing 20-100 mg resveratrol) daily, often divided. Topical: Formulations typically contain 0.1-1% resveratrol from the extract.
Suggested range
Oral: 200-1000 mg of extract daily. Topical: 0.1-1% concentration in final product.

Potential benefits

Benefits linked to this supplement form:

Things to watch for

Possible side effects linked to this form:

Health goals

Needs and goals this form may help with:

Other forms of Resveratrol

Compare absorption and active amounts with sibling forms:

Technical details â–¼

Chemical ID (CAS)

84744-66-7 (for extract); 501-36-0 (for resveratrol)

Physical properties

Typically a brown to reddish-brown powder. Soluble in ethanol, glycerin, and water (depending on formulation). Hygroscopic. Characteristic mild herbal odor.

How it’s made

Produced by harvesting the dried rhizomes and roots of Polygonum cuspidatum. The plant material is cleaned, dried, and milled. Bioactive compounds are extracted using solvents such as ethanol, water, or supercritical CO2. The extract is then concentrated, purified, and often standardized to a specific resveratrol or polydatin content via chromatographic methods.