Lu Cha
StarCamellia sinensis (L.) O. Kuntze
☯ TCM Properties
Clears the Head and Brightens the Eyes; Eliminates Irritability and Relieves Thirst; Resolves Phlegm; Promotes Digestion and Resolves Food Stagnation; Promotes Urination; Resolves Toxicity
Traditional Chinese Uses
Lu Cha (green tea) is a cool, bitter-sweet beverage-herb with a history of medicinal use in Chinese medicine spanning millennia. It clears internal Heat, relieves headaches and mental fogginess from Heat, aids digestion after rich meals, and quenches thirst. Modern research supports its antioxidant, cardiovascular, and metabolic benefits. It is best suited for those with robust constitutions and is used cautiously by those with cold or weak digestion, as its cold nature can weaken Spleen Yang with excessive consumption.
Western Herbalism Properties
Botanical Description
Camellia sinensis, the tea plant, is an evergreen shrub or small tree of the family Theaceae native to a broad region of southern China, northeastern India, Myanmar and northern Indochina, where it grows naturally as an understorey tree up to 10-15 m tall but is maintained at 1-1.5 m in cultivation by regular plucking. The alternate, leathery, elliptic to oblanceolate leaves are 4-15 cm long with finely serrate margins, dark glossy green above and lighter beneath, the young shoots silvery-pubescent. Solitary or paired axillary flowers about 2.5-4 cm across have five to seven white obovate petals surrounding numerous yellow stamens, and are followed by woody three-celled capsules containing one to three rounded brown seeds. For green tea (Lu Cha) the freshly plucked terminal shoots are heat-fixed (pan-fired or steamed) to inactivate polyphenol oxidase and then rolled and dried.
Active Constituents
(-)-Epigallocatechin-3-gallate (EGCG)
Flavan-3-ol (catechin)Concentration: The most abundant and pharmacologically important catechin, often 50–80% of the total catechin content of green tea
The signature green-tea polyphenol with potent antioxidant, anti-inflammatory and anticancer activity. It modulates drug-metabolising enzymes and transporters and is responsible for several documented herb–drug interactions.
Other catechins (EGC, ECG, EC, catechin)
Flavan-3-ols (catechins)Concentration: Together with EGCG make up the major polyphenol fraction of the leaf
Contribute the astringency and antioxidant capacity of green tea; support the traditional actions of clearing heat, relieving thirst and promoting digestion.
Caffeine
Purine (methylxanthine) alkaloidConcentration: Roughly 2–4% of the dry leaf
A CNS stimulant and mild diuretic underpinning the traditional functions of clearing the head, brightening the eyes, promoting urination and dispelling drowsiness.
L-Theanine
Non-protein amino acidConcentration: A characteristic free amino acid of tea leaves
Promotes relaxation without sedation and modulates the stimulant effect of caffeine, contributing to green tea's calming yet alertness-sharpening quality.
Flavonols (quercetin, kaempferol and glycosides)
Flavonol polyphenolsConcentration: Minor polyphenol constituents
Antioxidant flavonoids adding to the radical-scavenging and vascular-protective properties of the infusion.
Gallic acid and theogallin
Phenolic acidsConcentration: Present as free acids and catechin gallate esters
Antioxidant phenolics; gallic acid moieties on gallated catechins (EGCG, ECG) are key to transporter/enzyme interactions and to reduced non-heme iron absorption.
Vitamin K (phylloquinone)
Fat-soluble vitaminConcentration: Present in tea leaves; concentrated in the dried leaf and matcha
Relevant to the potential antagonism of vitamin-K-antagonist anticoagulants; large intakes of leaf material can reduce warfarin efficacy.
⚠ Drug Interactions
Bortezomib (and other boronic-acid proteasome inhibitors)
EGCG and other 1,2-benzenediol (catechol/pyrogallol) polyphenols react directly with the boronic-acid group of bortezomib, forming a boronate ester that inactivates its proteasome-inhibitory activity. This blocks bortezomib-induced ER stress and tumour-cell death in vitro and in vivo.
Clinical note: Patients on bortezomib (or MG-262/PS-IX-type boronic-acid inhibitors) should avoid green tea and EGCG supplements during treatment.
Nadolol (and other OATP1A2 substrate beta-blockers)
Green tea catechins inhibit the intestinal uptake transporter OATP1A2. In a controlled human study, green tea reduced nadolol Cmax and AUC by roughly 85% without changing renal clearance, attenuating its blood-pressure-lowering effect.
Clinical note: Separate green tea from nadolol dosing and monitor blood pressure; the interaction may extend to other OATP1A2-transported drugs.
Warfarin
Large volumes of green tea supply vitamin K, which can antagonise vitamin-K-antagonist anticoagulants and lower the INR; a classic case report described loss of anticoagulation with very high green-tea intake.
Clinical note: Keep green tea intake consistent and moderate; report large changes in consumption to the anticoagulation clinic and monitor INR.
Non-heme (dietary) iron
Tea tannins/gallated catechins chelate non-heme iron in the gut lumen and inhibit its absorption, which can worsen iron-deficiency when tea is taken with meals or iron supplements.
Clinical note: Take iron supplements and iron-rich meals at least 1–2 hours apart from green tea, especially in iron-deficiency anaemia.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 6-15g | Daily | — | — | — |
Preparation Methods
Infusion (steeped tea)
Parts: Dried unfermented leaf and bud
Steep roughly 2–3 g of leaf in hot (70–85°C) water for a few minutes and drink as a beverage to clear heat, relieve thirst, refresh the head and promote digestion. Lower temperatures preserve catechins and reduce bitterness.
Matcha (whole-leaf powder)
Parts: Powdered shade-grown leaf
Finely milled green-tea powder whisked into water so the whole leaf is consumed, giving higher catechin, caffeine and vitamin K intake per serving.
Standardized green tea extract
Parts: Leaf (concentrated polyphenol extract)
Concentrated catechin/EGCG extracts used as supplements; because they deliver much higher polyphenol doses than brewed tea, they carry greater interaction and (rarely) hepatotoxicity risk and should be used cautiously.
Clinical Studies
Green Tea Ingestion Greatly Reduces Plasma Concentrations of Nadolol in Healthy Subjects
Ten healthy subjects took 30 mg nadolol after 14 days of green tea (700 mL/day) or water. Green tea decreased nadolol Cmax and AUC0–48 by ~85% without altering renal clearance, and blunted its systolic-blood-pressure-lowering effect. Uptake assays identified nadolol as an OATP1A2 substrate, attributing the interaction to intestinal OATP1A2 inhibition by catechins.
Green tea polyphenols block the anticancer effects of bortezomib and other boronic acid-based proteasome inhibitors
EGCG and related polyphenols with 1,2-benzenediol moieties prevented bortezomib-induced tumour-cell death in vitro and in vivo. EGCG reacted directly with bortezomib's boronic acid, blocking proteasome inhibition, ER stress and caspase-7 activation. The authors concluded green tea products may be contraindicated during bortezomib therapy.
Historical Texts
Cha Jing (The Classic of Tea), Lu Yu
Tang dynasty, c. 760 CEBencao Gangmu (Compendium of Materia Medica), Li Shizhen
Ming dynasty, 1578Shennong Bencao Jing tradition
Han dynasty compilation (classical era)References
- Kyriacou C, et al.. Green Tea Catechins as Perpetrators of Drug Pharmacokinetic Interactions . Clinical Pharmacology & Therapeutics (2025) [DOI]
- Werba JP, Misaka S, et al.. Update of green tea interactions with cardiovascular drugs and putative mechanisms . Journal of Food and Drug Analysis (2018) [DOI]
- Golden EB, Lam PY, Kardosh A, et al.. Green tea polyphenols block the anticancer effects of bortezomib and other boronic acid-based proteasome inhibitors . Blood (2009) [DOI]
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.
📝 Notes
Public notes from the community and your own private notes on Lu Cha.
No notes yet.