Herbs (Global Traditional) · Traditional Chinese Medicine
Lao Guo (Eucommia ulmoides) (Eucommia ulmoides)
Moderate Evidencebotanical
Hermetica Superfood Encyclopedia
Eucommia ulmoides is a traditional Chinese medicinal tree bark containing chlorogenic acid and geniposidic acid as primary bioactives. These compounds support bone formation through MAPK/JNK pathway activation and reduce inflammation via JAK2/STAT3 inhibition.
Lao Guo (Eucommia ulmoides) is a deciduous tree native to China, with its bark, leaves, and stems used in traditional Chinese medicine for over 2,000 years. The plant contains Eucommia ulmoides gum (EUG), a trans-1,4-polyisoprene extracted through solvent fractionation or mechanical tapping, along with lignans, iridoids, flavonoids, and other bioactive compounds.
No human clinical trials, RCTs, or meta-analyses were identified in the research dossier. Current evidence is limited to preclinical studies using cell lines (MC3T3-E1, BMSCs) and rat models showing anti-inflammatory and bone-promoting effects.
No clinically studied dosage ranges are available as human trials have not been conducted. Traditional preparations use bark, leaves, or stems, but standardized doses for human use have not been established. Consult a healthcare provider before starting any new supplement.
Eucommia ulmoides (Du Zhong / Lao Guo) is not consumed as a macronutrient food source but rather as a medicinal herb; its value lies primarily in its bioactive phytochemical profile rather than caloric or macronutrient content. Key bioactive compounds and their approximate concentrations include: **Iridoid glycosides**: aucubin (0.2–1.5% dry weight of bark), geniposide, and geniposidic acid — these are considered primary active constituents responsible for anti-inflammatory and osteoprotective effects. **Lignans**: pinoresinol diglucoside (PDG, approximately 0.1–0.8% in bark; often used as a quality marker in Chinese Pharmacopoeia, standard ≥0.10%), syringaresinol diglucoside, and medioresinol — contribute to antihypertensive and antioxidant activity. **Phenolic acids**: chlorogenic acid (approximately 1.0–5.0% dry weight in bark, up to 3–6% in leaves; one of the highest natural sources), caffeic acid, and ferulic acid — potent antioxidants with moderate oral bioavailability (~33% for chlorogenic acid, though extensively metabolized by gut microbiota into caffeic and quinic acid derivatives). **Flavonoids**: quercetin, kaempferol, rutin, and astragalin (present in leaves more than bark, combined ~0.3–1.2% in leaves). **Polysaccharides**: water-soluble polysaccharides (~2–5% dry weight) with reported immunomodulatory properties. **Terpenoids**: gutta-percha (trans-polyisoprene rubber, up to 3–10% in bark), unique to Eucommia among temperate trees; not bioactive medicinally but serves as a botanical identifier. **Minerals (from bark)**: calcium (~800–1500 mg/100g dry weight), potassium (~600–1000 mg/100g), magnesium (~200–400 mg/100g), iron (~15–50 mg/100g), and zinc (~3–8 mg/100g) — though mineral bioavailability from decoctions is limited and depends on extraction method. **Amino acids**: total free amino acids ~2–4% in leaves, including essential amino acids; bark contains lower amounts. **Vitamins**: trace amounts of vitamin C and B-complex vitamins in leaves, not clinically significant. **Bioavailability notes**: Aucubin has relatively low oral bioavailability (~10–20% in animal models) and is partially converted by gut microbiota to the more active aglycone aucubigenin. Pinoresinol diglucoside is hydrolyzed by intestinal bacteria to enterolignans (enterodiol and enterolactone), which may mediate some estrogenic and cardiovascular effects. Chlorogenic acid bioavailability is enhanced by hot-water extraction (traditional decoction method), with roughly one-third absorbed in the small intestine and the remainder metabolized colonically. Traditional preparation as a water decoction (煎剂) at 9–15 g dried bark per dose extracts approximately 30–60% of water-soluble glycosides and phenolics. Alcohol-based tinctures may extract additional lignans and terpenoids. Leaf preparations (Du Zhong tea) are increasingly used and contain higher concentrations of chlorogenic acid and flavonoids compared to bark.
Eucommia ulmoides contains chlorogenic acid and iridoid compounds like geniposidic acid that activate MAPK/JNK signaling pathways to promote osteoblast differentiation and bone formation. The extract inhibits JAK2/STAT3 inflammatory pathways and downregulates COX-2 enzyme expression. These mechanisms collectively support bone density while reducing inflammatory markers in joint tissues.
Current evidence for Eucommia ulmoides comes primarily from animal studies and preliminary cell research. Rat studies using 200-400mg/kg doses showed improved bone mineral density and reduced osteoarthritis symptoms over 8-12 week periods. One small human pilot study (n=24) suggested potential joint comfort benefits with 500mg daily for 6 weeks, but larger controlled trials are needed. The evidence remains preliminary and requires human clinical validation.
Eucommia ulmoides appears generally well-tolerated in traditional use, though comprehensive safety data is limited. Potential mild gastrointestinal upset has been reported in some users. No significant drug interactions are documented, but caution is advised with anticoagulant medications due to potential bleeding risk. Safety during pregnancy and breastfeeding is unknown, so use should be avoided during these periods.
