Longevity, Hair Health, and Safety

How Polygonum multiflorum (He Shou Wu / Fo-Ti) supports hair growth, anti-aging via the TSG antioxidant, cardiovascular health — and why processing and dosage matter for liver safety

He Shou Wu (Polygonum multiflorum, also known as Fo-Ti in North America) is one of the most revered roots in traditional Chinese medicine — used for over two thousand years as a longevity tonic believed to darken graying hair, strengthen the kidneys and liver, and slow aging. Modern research has found real biochemical mechanisms behind several of these traditional claims. The root's primary active compound, a stilbene glucoside called TSG, is a potent antioxidant with neuroprotective and cardiovascular effects. [3] Separate studies confirm that root extracts genuinely stimulate hair follicle cycling and counteract androgen-driven hair thinning. [2] [5] However, He Shou Wu carries a meaningful liver injury risk — particularly from raw or improperly prepared forms — and this cannot be dismissed. [4] Understanding how the herb is processed, and using appropriate doses, is essential for anyone considering it.

What's in He Shou Wu

The root contains hundreds of identified compounds. Three chemical families drive most of the biological activity:

Stilbene glucosides — primarily TSG (2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside). This is the compound most responsible for antioxidant, neuroprotective, cardiovascular, and anti-aging effects. TSG has stronger free radical-scavenging activity than resveratrol in several assays. [3]

Anthraquinones — including emodin, physcion, and chrysophanol. These have laxative effects and are the compounds most strongly implicated in liver toxicity. They are significantly reduced by traditional processing methods. [4]

Stilbene dimers and flavonoids — contributing additional anti-inflammatory and anti-aggregation effects.

The distinction between raw He Shou Wu (sheng he shou wu) and processed He Shou Wu (zhi he shou wu) matters enormously for both efficacy and safety. Traditional processing involves steaming the root with black bean juice for hours, which reduces anthraquinone content and alters the ratio of bioactive compounds. Most of the documented liver injury cases involve raw or minimally processed preparations. Reputable supplements for internal use should specify the processed form.

Hair: The Most-Studied Traditional Claim

He Shou Wu's reputation for reversing gray hair and preventing hair loss has significant mechanistic support, though robust human clinical trials are still limited.

Stimulating Hair Follicle Growth

Hair cycles through active growth (anagen), regression (catagen), and rest (telogen). He Shou Wu extract promotes the transition from telogen back into active anagen growth. In mouse studies, topical application upregulated two key hair growth signals — Sonic hedgehog (Shh) and β-catenin — both essential for follicle activation, and increased the number and size of hair follicles. [2]

In human dermal papilla cell cultures (the connective tissue cells that govern hair follicle activity), PM extract extended the anagen growth phase and significantly reduced the suppressive effects of dihydrotestosterone (DHT) — the androgen responsible for androgenetic alopecia (pattern hair loss). The extract appeared to work partly by inhibiting 5α-reductase, the enzyme that converts testosterone to DHT. [5]

Restoring Hair Pigmentation

In C57BL/6 mice with hydrogen peroxide-induced hair graying, both raw and processed PM extracts — as well as isolated TSG — restored pigmentation by upregulating the melanin synthesis pathway: increasing expression of MITF (the master regulator of melanocytes), tyrosinase (TYR), and related enzymes TRP-1 and TRP-2. The processed form showed stronger pigmentation restoration than raw in this model. [6]

The proposed mechanism: TSG and related compounds protect melanocytes from oxidative stress (a major driver of pigment cell loss with aging) and stimulate melanogenesis signaling. This aligns with the traditional use, though human trials confirming gray hair reversal at clinically meaningful levels are still lacking.

Antioxidant and Anti-Aging Effects of TSG

TSG is the compound that has attracted the most pharmacological research. A 2025 systematic review synthesized evidence across dozens of studies and found consistent anti-aging effects across multiple organ systems:

Neuroprotection: TSG protects dopaminergic and cholinergic neurons from oxidative damage, with relevance to Alzheimer's and Parkinson's disease models. It inhibits amyloid-β aggregation and reduces neuroinflammation.
Cardiovascular protection: TSG reduces atherosclerotic plaque formation, lowers LDL oxidation, protects endothelial cells from oxidized LDL damage, and reduces markers of arterial senescence.
Mitochondrial support: TSG activates the AMPK/SIRT1/PGC-1α signaling axis — the same longevity pathway targeted by caloric restriction and exercise — improving mitochondrial biogenesis in aging cells.
Bone density: TSG supports osteoblast differentiation and reduces osteoclast activity, showing protective effects in osteoporosis models.
Hematopoietic stem cell rejuvenation: TSG has been shown to rejuvenate aging blood-forming stem cells, which typically drift toward inflammatory myeloid lineages with age. [3]

Cholesterol and Cardiovascular Support

Clinical reviews note that PM preparations have demonstrated lipid-lowering effects in human studies — reducing total cholesterol and LDL, with modest increases in HDL — consistent across multiple small trials. The anthraquinone stilbene-glycoside TSG appears to inhibit cholesterol synthesis and enhance LDL receptor expression. [1]

Liver Safety: What You Need to Know

This cannot be treated as a footnote. He Shou Wu is one of the most commonly cited traditional Chinese herbs in reports of drug-induced liver injury, with cases ranging from mild transaminase elevation to acute liver failure.

A retrospective clinical study of 29 patients with He Shou Wu-induced liver injury found:

Median patient age 53 years; 76% were women
Most common presentation: jaundice (79% of cases)
Liver biopsy patterns: primarily acute cholestatic or hepatocellular injury
Most patients recovered fully after stopping the herb; however, chronic liver disease and death have occurred in documented cases [4]

The liver injury is thought to involve immune-mediated hypersensitivity triggered by stilbene glycosides interacting with specific metabolic variants (notably CYP1A2 polymorphisms), rather than simple dose-dependent toxicity. This means not everyone is equally at risk — but there is no reliable pre-screening test available outside research settings.

Practical guidance for safety:

Always use the processed (zhi) form for internal supplementation — not raw
Stick to standard doses: typically 500–1,500 mg/day of standardized processed extract for general use; traditional tonic doses in TCM formulas are 9–15 g of prepared root per day
Do not use for extended periods without liver function monitoring — most reported injuries occurred after weeks to months of regular use
Avoid combining with other potentially hepatotoxic substances (alcohol, acetaminophen, hepatotoxic herbs)
Stop immediately if you notice jaundice, dark urine, or unexplained fatigue
Those with pre-existing liver conditions or CYP enzyme polymorphisms should approach with particular caution or avoid entirely

See our Milk Thistle page for a complementary herb with liver-protective properties, and our Astragalus page for a well-tolerated TCM longevity herb with a stronger safety record.

Evidence Review

Bounda & Feng 2015 — Clinical Studies Review

This review [1] in Pharmacognosy Research synthesized clinical pharmacokinetics and efficacy data for PM. Key findings: human trials demonstrate cholesterol-lowering effects — one trial in hyperlipidemic patients showed PM preparations reduced total cholesterol by approximately 15% and LDL by 12% versus baseline after 12 weeks. Other reviewed trials documented improvements in neurodegenerative symptom markers and sleep quality. The authors note that most trials were conducted in China with small sample sizes and that methodological quality varies substantially, limiting generalizability. The pharmacokinetic data show TSG is well-absorbed orally with peak plasma concentrations within 1–2 hours and a half-life of approximately 4 hours, supporting once or twice daily dosing.

Park, Zhang & Park 2011 — Topical Hair Growth in Mice

This study [2] from Journal of Ethnopharmacology assessed topical PM extract on the shaved dorsal skin of C57BL/6 mice in telogen (resting) phase. Polygonum multiflorum extract was applied daily; control mice received vehicle only.

Results:

Hair growth was significantly accelerated in the PM group versus control
Immunohistochemistry showed earlier and stronger expression of β-catenin in hair follicle cells — a key signal for the dermal papilla to re-enter anagen
Shh (Sonic hedgehog) expression was upregulated at the follicle base, confirming activation of the anagen-induction pathway
Follicle number and size were greater in the PM group

The study is animal-only (no human subjects), limiting direct clinical translation, but the molecular mechanisms identified are consistent with known human hair follicle biology and provide a credible basis for the traditional use.

Shin et al. 2020 — Human Dermal Papilla Cells and Androgen Antagonism

This cell culture study [5] in BMC Complementary Medicine and Therapies used human dermal papilla cells (DPCs) — the primary regulatory cells of hair follicles — isolated from patients with and without androgenetic alopecia.

PM extract treatment:

Significantly extended the anagen survival phase of DPCs in culture, measured by reduced apoptosis and maintained growth factor secretion
Reduced DHT-induced suppression of key hair growth factors including IGF-1 and VEGF in balding DPCs
Inhibited 5α-reductase activity in cell culture, reducing conversion of testosterone to DHT
Upregulated Wnt/β-catenin signaling in treated cells

The study design (human cells, androgenic alopecia model) is more clinically relevant than rodent studies, and the dual mechanism — both extending the growth phase and blocking the androgen pathway that causes miniaturization — provides a plausible explanation for why He Shou Wu has been used specifically for age-related and androgen-driven hair loss. Clinical RCTs in human patients are needed to confirm the effect size.

Han et al. 2015 — Hair Graying Mechanisms

This study [6] in BioMed Research International investigated the mechanisms by which PM root preparations reverse oxidative gray hair in C57BL/6 mice.

The oxidative graying model used hydrogen peroxide to suppress melanogenesis. Both raw PM root, processed PM root (steamed with black bean), and isolated TSG were tested.

Key findings:

All three treatments upregulated MITF (microphthalmia-associated transcription factor, the master controller of melanocyte identity and function)
Tyrosinase (TYR) — the rate-limiting enzyme in melanin synthesis — was significantly increased in all treatment groups
TRP-1 and TRP-2 expression was restored toward normal levels
The processed form (PMRP) showed stronger restoration of pigmentation than raw PM in this model, suggesting that processing does not eliminate the pro-pigmentation activity while reducing anthraquinone content
TSG alone partially reproduced the effect, confirming it is a meaningful contributor to this mechanism

The evidence supports a specific molecular basis for the traditional hair-darkening claim. Oxidative stress is a genuine driver of premature and age-related graying, and protecting melanocytes from peroxide damage while restoring tyrosinase activity is a mechanistically coherent strategy.

Zhu et al. 2025 — TSG Anti-Aging Systematic Review

This comprehensive 2025 systematic review [3] in International Journal of Molecular Sciences synthesized evidence from dozens of experimental studies on TSG's anti-aging effects across multiple biological systems.

Notable data points from the compiled evidence:

TSG extended lifespan in multiple model organisms and delayed senescence markers in cell culture
In Parkinson's disease models, TSG reduced dopaminergic neuron loss by 40–60% via PI3K/Akt pathway activation
TSG reduced atherosclerotic plaque area by approximately 35% in ApoE-knockout mouse models
In aging hematopoietic stem cell models, TSG activated Tet2-dependent epigenetic reprogramming, partially rejuvenating the lymphoid differentiation capacity that declines with age
AMPK/SIRT1/PGC-1α activation was confirmed across multiple studies, with TSG increasing mitochondrial biogenesis markers comparably to moderate-dose resveratrol

Importantly, the review distinguishes TSG's antioxidant mechanism from the anthraquinones implicated in hepatotoxicity — TSG itself is not considered hepatotoxic in experimental models. The safety concern centers on emodin and related anthraquinones, which are reduced in the processed form and further separated in standardized TSG extracts.

Wang et al. 2019 — Liver Injury Clinical Series

This retrospective clinical study [4] from Beijing Friendship Hospital in Liver International is among the most rigorous analyses of He Shou Wu hepatotoxicity in a clinical population.

Methodology: All patients admitted to the hospital between August 2005 and August 2017 who met RUCAM (Roussel Uclaf Causality Assessment Method) criteria for PM-induced drug-induced liver injury were enrolled. RUCAM is the standard validated tool for attributing liver injury to a specific agent.

Results (n=29 patients):

Median age: 53 years (range 15–74); 75.9% women
Common presenting symptoms: jaundice (79.3%), fatigue, anorexia
Biochemistry: significant elevations in ALT (median ~700 U/L), ALP, and total bilirubin
Biopsy findings (n=9): acute cholestatic hepatitis (6), acute hepatocellular injury (2), chronic hepatocellular injury (1)
Outcomes: most patients recovered fully after stopping PM; one patient developed chronic liver disease; one death attributed to acute liver failure

The study design (retrospective, single-centre) is limited, and the study cannot determine incidence rate (how often liver injury occurs in PM users overall). However, the pattern of injury — predominantly cholestatic, immune-mediated, not simply dose-dependent — is consistent with other reports and with proposed mechanisms involving immune hypersensitivity reactions to stilbene glycoside metabolites in genetically susceptible individuals.

Evidence Strength Summary

Hair growth stimulation: Moderate — consistent mechanistic evidence in animal and cell studies; human RCTs are lacking. Confidence: moderate.

Hair graying reversal: Moderate — mechanistic data on melanocyte protection and tyrosinase restoration is compelling; human clinical evidence is limited. Confidence: moderate.

Antioxidant and anti-aging (TSG): Moderate to high for mechanisms; mostly preclinical. Human trials are sparse but consistent with the biology. Confidence: moderate.

Cholesterol lowering: Moderate — multiple small clinical trials, but quality is variable and trials are predominantly from one country. Confidence: moderate.

Liver injury risk: High — well-documented across multiple case series, systematic reviews, and biologically plausible mechanisms. This is a real risk that must be respected. Confidence: high.

Overall: He Shou Wu has genuine biological credibility for several of its traditional uses, particularly hair-related applications and antioxidant/anti-aging effects via TSG. It should not be dismissed as folk medicine — but the hepatotoxicity risk is real enough that it warrants careful use of processed forms, appropriate dosing, and awareness of warning signs.

References

Review of clinical studies of Polygonum multiflorum Thunb. and its isolated bioactive compoundsBounda GA, Feng YU. Pharmacognosy Research, 2015. PubMed 26130933 →
Topical application of Polygonum multiflorum extract induces hair growth of resting hair follicles through upregulating Shh and β-catenin expression in C57BL/6 micePark HJ, Zhang N, Park DK. Journal of Ethnopharmacology, 2011. PubMed 21419834 →
2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-glucoside (TSG) from Polygonum multiflorum Thunb.: A Systematic Review on Anti-AgingZhu C, Li J, Tang W, Li Y, Lin C, Peng D, Yang C. International Journal of Molecular Sciences, 2025. PubMed 40244282 →
Clinicopathological features of He Shou Wu-induced liver injury: This ancient anti-aging therapy is not liver-friendlyWang Y, Jiang Y, Fan X, Tan H, Zeng H, Wang Y, Chen P, Huang M, Bi H. Liver International, 2019. PubMed 30066422 →
Polygonum multiflorum extract support hair growth by elongating anagen phase and abrogating the effect of androgen in cultured human dermal papilla cellsShin JY, Choi Y, Kim J, Park SY, Nam YJ, Lee SY, Jeon JH, Jin MH, Lee S. BMC Complementary Medicine and Therapies, 2020. PubMed 32398000 →
Mechanistic Studies on the Use of Polygonum multiflorum for the Treatment of Hair GrayingHan MN, Lu JM, Zhang GY, Yu J, Zhao RH. BioMed Research International, 2015. PubMed 26640791 →