He Shou Wu (Fo-Ti, Polygonum Multiflorum): Traditional Use and Liver Injury Reports

What it is

He Shou Wu is the root of Polygonum multiflorum Thunb. It is called Fo-Ti in North America. It is official in the Chinese Pharmacopoeia. [1]

Traditional use

In traditional Chinese medicine the raw root and the processed root are treated as two different materials. Traditional texts describe the processed root as tonifying the liver, nourishing blood and "blackening hair". [2] The NIDDK LiverTox entry says extracts have been used for centuries for backache, dizziness, liver disease, graying of the hair and constipation. [3] These are traditional uses, not tested outcomes.

What research shows

Evidence label: traditional use only, with preclinical research. The reviews we read describe mostly animal and cell studies of the processed root for liver conditions. [2] A review of clinical studies lists sleep disorders, dyslipidemia (raised blood fats) and neurodegenerative disease as areas where human data exist, but it is a summary of what was published and does not show that the root is an effective treatment. [1] We did not find a large, well-controlled trial showing a benefit that outweighs the liver risk below. Proper evidence not found for hair color, hair loss or anti-aging in people; we searched PubMed for trials and reviews and found only the reviews cited here.

Liver injury reports

Evidence label: evidence of harm (case reports and cohort data).

• LiverTox, a US government database on drug-induced liver injury, says Polygonum multiflorum has been implicated in numerous reports of acute liver injury that can be severe and even fatal. [3]
• A 2019 systematic review of herb-induced liver injury across 31 studies named Polygonum multiflorum among the main herbs responsible. [4]
• A 2026 review of 571 published cases of liver injury linked to Chinese medicines found it among the three most frequently documented herbs. [5]
• Reviews note that reports on both the raw root and the processed root have increased, and that the compounds responsible are not yet identified. [6]

Why some people are affected

Reviews describe this as an immune-mediated, idiosyncratic reaction, meaning it affects a minority of users unpredictably rather than everyone. [7] A study in Han Chinese patients found a gene variant, HLA-B*35:01, in 45.4% of patients with the injury compared with 2.7% of the general population. In a prospective group of 72 outpatients, a symptom-free rise in liver enzymes was far more common in carriers (37.5%) than non-carriers (4.7%). [8] This is a research finding in one population, not a test you can use to make taking it safe.

Processing and quality

Reviews say processing lowers the toxicity of the raw root, but also that the processing mechanism is unclear and quality control of the processed product is lacking. [9] Another review stresses that improper use of processed root can cause liver injury, and that standardization of processing matters. [2] In practice this means a label saying "prepared" is not a guarantee of safety.

Where to read more

For the wider picture see Liver Injury From Chinese Herbal Products and Chinese Herbal Products: Quality, Contamination and Medicine Interactions. For general supplement liver safety see Liver Safety and Supplements. The herb sits within Chinese Herbal Medicine, and the term "tonify" is explained in Qi, Yin and Yang, Five Phases and Meridians as Traditional Concepts.