Fo-Ti is one of the better-known Chinese herbal medicines in the West, often marketed alongside ginseng for anti-ageing and hair health. But I should be upfront: the evidence base here is thin, and the safety concerns are real.

What is Fo-Ti?

Fo-Ti (Polygonum multiflorum, also called He Shou Wu) is a climbing plant in the buckwheat family. The medicinal part is its tuberous root, which is dark brown when harvested. The name “He Shou Wu” translates roughly as “Mr He’s black hair” - a reference to a Tang Dynasty legend about a man whose grey hair supposedly turned black after taking the herb.

The herb was first formally documented in the Kaibao Bencao, a Chinese pharmacopoeia published during the Song Dynasty (around 973 CE). It’s now commercially cultivated in China and sold worldwide as a dietary supplement.

Raw versus processed forms

Traditional Chinese medicine distinguishes between two forms of Fo-Ti, and this matters because they’re used quite differently:

Raw Fo-Ti (sheng he shou wu): The unprocessed dried root. In traditional use, it’s prescribed for constipation (it has laxative effects), skin infections, and detoxification. The raw form is considered more cooling and has stronger purgative action.

Processed Fo-Ti (zhi he shou wu): The root is stewed with black beans and sometimes rice wine, which changes its chemical composition. The processed form is traditionally used for different purposes: supporting liver and kidney function, nourishing blood, and treating greying hair. Most commercial supplements use the processed form.

This distinction isn’t just traditional - the processing does change the phytochemical profile. Processed Fo-Ti has lower levels of emodin (an anthraquinone with laxative and potentially hepatotoxic effects) and higher levels of some stilbene glycosides.

Active compounds

Researchers have identified several classes of compounds in Fo-Ti:

Stilbene glycosides (including 2,3,5,4’-tetrahydroxystilbene-2-O-β-glucoside)
Anthraquinones (emodin, physcion, rhein)
Phenolic acids
Flavonoids
Phospholipids

The stilbene glycosides get the most attention from researchers because they have antioxidant properties in laboratory studies. Whether these translate to meaningful effects in humans at typical supplement doses is another question.

What are the potential benefits of Fo-Ti?

I’ve reviewed the available clinical research. The honest summary: most evidence comes from animal studies or small human trials, and nothing here would count as well-established in Western medicine.

1. Alzheimer’s disease - mixed results

Alzheimer’s disease affects memory, language, and cognitive function. It’s a devastating condition with limited treatment options, so there’s understandable interest in alternative approaches.

One clinical study from 2010 enrolled 209 patients with Alzheimer’s disease and compared a combined Fo-Ti extract against a single-herb Fo-Ti extract and conventional treatment over 12 weeks [1]. The combination extract group showed better improvements on cognitive assessments (the Mini-Mental State Examination and Activities of Daily Living Scale) compared to the other groups.

My honest assessment: this is one study, from over a decade ago, with a relatively short duration. The combination product makes it hard to attribute effects specifically to Fo-Ti. I wouldn’t recommend Fo-Ti for dementia based on this evidence, but it’s at least a data point suggesting the herb might warrant more research.

2. Greying hair - animal data only

The traditional use of Fo-Ti for greying hair is arguably its most famous claim. The “He Shou Wu” legend specifically involves hair colour restoration.

An animal study from 2017 tested Fo-Ti extracts on mice whose hair had been discoloured using hydrogen peroxide [2]. The extract (particularly the crude/raw form) increased melanin production and appeared to reverse the artificial greying.

The mechanism seems to involve upregulation of melanocyte-stimulating hormone (α-MSH) and tyrosinase, an enzyme involved in melanin synthesis.

Here’s my scepticism: hydrogen peroxide-induced greying in mice is quite different from natural age-related greying in humans. We don’t have any proper clinical trials showing Fo-Ti can reverse grey hair in people. The traditional reputation may come from confirmation bias over centuries rather than genuine efficacy.

3. Hair loss - also animal data only

Hair loss affects roughly half of men and women by middle age. Existing treatments (finasteride, minoxidil) have variable effectiveness and side effects, so there’s a market for alternatives.

A 2011 animal study applied Fo-Ti extract topically to mice and found it increased hair follicle number and size [3]. The researchers suggested it might promote hair growth.

Again, topical application in mice doesn’t tell us much about oral supplements in humans. Hair growth studies are notoriously difficult because of the placebo effect and natural hair cycling. Without controlled human trials, I’d treat this as preliminary at best.

4. Bone health - early-stage research

Osteoporosis involves loss of bone mass and deterioration of bone microstructure, increasing fracture risk. It’s common in postmenopausal women and older adults generally.

A 2019 animal study found that Fo-Ti water extract improved bone density and bone mass in rats by affecting osteoclast-related genes [4]. Osteoclasts are cells that break down bone tissue, so inhibiting them could theoretically preserve bone.

This is interesting basic research but hasn’t been tested in humans. For bone health, there are better-studied options like calcium, vitamin D, and resistance exercise.

5. Allergic asthma - one animal study

Allergic asthma is a chronic inflammatory lung condition affecting over 300 million people worldwide. It causes wheezing, difficulty breathing, and coughing, typically triggered by allergens.

A 2016 animal study found that Fo-Ti reduced allergic asthma symptoms in mice by inhibiting inflammation, goblet cell proliferation (mucus-producing cells), and airway hyperresponsiveness [5].

One animal study doesn’t support human use. Asthma is a serious condition that requires proper medical management. I wouldn’t suggest anyone use Fo-Ti as an asthma treatment based on this research.

Are there side effects of Fo-Ti?

Yes, and they can be serious. This is where the rubber meets the road.

Liver toxicity

The biggest concern with Fo-Ti is hepatotoxicity (liver damage). Multiple case reports have documented liver injury associated with Fo-Ti use, including some cases requiring liver transplantation [6].

The mechanism isn’t fully understood, but may involve:

Anthraquinone compounds (especially emodin)
Individual genetic susceptibility
Interactions with other herbs or medications
Quality control issues in supplements

The risk appears higher with:

Higher doses
Prolonged use
The raw (unprocessed) form
Pre-existing liver conditions

The UK’s Medicines and Healthcare products Regulatory Agency (MHRA) has issued warnings about Fo-Ti products, and Australia’s Therapeutic Goods Administration requires warning labels [7].

Gastrointestinal effects

Common side effects include:

Diarrhoea (especially with raw Fo-Ti, which has laxative properties)
Nausea
Abdominal pain
Vomiting

These are more likely with the unprocessed form due to its higher anthraquinone content.

Safety precautions (13 contraindications)

Given the potential risks, here’s who should avoid Fo-Ti:

Anyone without medical supervision - Don’t self-treat with Fo-Ti. If you’re interested in trying it, discuss with a healthcare provider who can monitor for problems.
Children - Safety hasn’t been established in children.
Pregnant or breastfeeding women - The anthraquinones may affect foetal development and can pass into breast milk, potentially causing diarrhoea in nursing infants.
People with diabetes or taking blood sugar medications - Fo-Ti may affect blood glucose levels. Common diabetes medications that could interact include glimepiride, glyburide, insulin, pioglitazone, rosiglitazone, and glipizide.
People with liver or kidney disease - Given the documented hepatotoxicity risk, anyone with compromised liver or kidney function should avoid Fo-Ti entirely.
People with hormone-sensitive conditions - Fo-Ti may have oestrogenic effects. Avoid if you have breast cancer, uterine cancer, ovarian cancer, endometriosis, or uterine fibroids.
People on anticoagulants or with bleeding disorders - Fo-Ti may have anticoagulant properties that could increase bleeding risk. This includes people taking warfarin, aspirin, clopidogrel, or other blood thinners.
Two weeks before surgery - Stop Fo-Ti at least two weeks before any scheduled surgery due to potential effects on blood clotting and blood sugar.
People taking digoxin - Fo-Ti may increase digoxin side effects, potentially causing dangerous cardiac effects.
People taking medications metabolised by cytochrome P450 enzymes - Fo-Ti may affect how these drugs are processed, changing their effectiveness or increasing side effects. This is a long list including: amitriptyline, haloperidol, ondansetron, propranolol, theophylline, verapamil, omeprazole, lansoprazole, pantoprazole, diazepam, nelfinavir, diclofenac, ibuprofen, meloxicam, piroxicam, celecoxib, losartan, lovastatin, ketoconazole, itraconazole, fexofenadine, and triazolam.
People taking potentially hepatotoxic medications - Combining Fo-Ti with other liver-stressing drugs compounds the risk. These include paracetamol (acetaminophen), amiodarone, carbamazepine, isoniazid, methotrexate, methyldopa, fluconazole, erythromycin, phenytoin, and statins (lovastatin, pravastatin, simvastatin).
People taking stimulant laxatives - Fo-Ti has its own laxative effect. Combining with bisacodyl, cascara, castor oil, or senna could cause excessive fluid and electrolyte loss.
People taking diuretics - The combination may cause excessive electrolyte loss (sodium, potassium). This includes chlorothiazide, chlorthalidone, furosemide, and hydrochlorothiazide. People with frequent urination or bladder conditions should be particularly cautious about fluid and electrolyte balance.

The bottom line

Fo-Ti has a long history in traditional Chinese medicine, but the clinical evidence for its benefits is weak - mostly animal studies and small trials. The safety concerns, particularly liver toxicity, are better documented than the benefits.

If you’re interested in Fo-Ti for hair health or cognitive function, there are better-studied alternatives. For greying hair, the evidence doesn’t support any supplement. For cognitive health, fish oil and regular exercise have much stronger evidence bases.

If you still want to try Fo-Ti, use only the processed form, keep doses low, and have your liver function monitored regularly. But honestly, I’d question whether the potential risk is worth the uncertain benefit.

References

Zhong ZM, et al. Clinical study of Fo-Ti compound for Alzheimer’s disease. Chinese Journal of Integrative Medicine. 2010;16(3):224-8. https://pubmed.ncbi.nlm.nih.gov/20622335/
Sun YN, et al. Hair growth-promoting effect of He Shou Wu glycosides in cultured dermal papilla cells of human scalp hair follicles and C57BL/6 mice. Journal of Ethnopharmacology. 2017;195:289-295. https://pubmed.ncbi.nlm.nih.gov/27984226/
Park HJ, et al. Hair growth-promoting effect of Polygonum multiflorum on mouse models and C57BL/6 mice. Journal of Ethnopharmacology. 2011;134(3):753-60. https://pubmed.ncbi.nlm.nih.gov/21419834/
Liu Y, et al. Polygonum multiflorum Thunb. water extract promotes osteogenic differentiation and bone formation through BMP signaling pathway. Journal of Ethnopharmacology. 2019;234:18-27. https://pubmed.ncbi.nlm.nih.gov/31328115/
Lin L, et al. Inhibition of allergic airway inflammation by the ethanol extract of Polygonum multiflorum in a murine asthma model. International Journal of Molecular Medicine. 2016;37(5):1265-72. https://pubmed.ncbi.nlm.nih.gov/26916919/
Lei X, et al. Liver injury associated with Polygonum multiflorum Thunb.: a systematic review of case reports and case series. Evidence-Based Complementary and Alternative Medicine. 2019;2019:9586471. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6745159/
Medicines and Healthcare products Regulatory Agency. Herbal medicines containing Polygonum multiflorum: risk of liver injury. Drug Safety Update. 2006. https://www.gov.uk/drug-safety-update/herbal-medicines-containing-polygonum-multiflorum-risk-of-liver-injury