Camellia sinensis
Tea plant
Generally recognised as safeOther names: Tea plant, Green tea
Tea plant—widespread culture in Myanmar and neighbouring countries.
Evergreen shrub to small tree with serrated leaves.
- Family
- Theaceae
- Plant type
- Shrub / tree
What the safety levels mean (expand legend)
- Generally recognised as safe. Often a common herb with reasonable harvest and use; still read the specific warnings on the card.
- Information. Primarily informational — details in the text and warnings below matter most.
- Caution. Needs extra care (dose, duration, sensitive groups, interactions).
- Risky. Significant risks — verify sources, contraindications and professional guidance.
- Not for home experimentation. Not suitable to experiment with at home without knowledge and certainty.
- High risk for internal use. Particular risk with internal use (e.g. alkaloids); avoid prolonged or irresponsible dosing.
- Not specified. Level not filled in yet — rely on individual warnings and links below.
Photograph on Wikimedia Commons (Public domain).
Plant habit
Safety — read before use
For this herb it is important to check warnings, mix-ups and cautions. Start with the Safety section.
Quick overview
A practical summary; details are in the sections below.
- Safety grade
- Generally recognised as safe details
- Scientific sources on the card
- Yes — sources are listed with claims Science section
- When and what to harvest
- Leaf — April–May
- Processing methods
Herbal infusion (tea), Powder, Culinary use
All methods and recipes on the card- Topics and symptoms
Fatigue and low energy, Focus and attention
Topics section, Symptoms overview
Identification and mix-ups
Ornamental flowers; leaf harvest follows tea culture.
Possible mix-ups and risks
Ornamental camellias by cultivation purpose.
Similar herbs
No related herbs are linked yet.
Topics and symptoms
More topics are in the symptoms and topics overview.
- Fatigue and low energyTraditional· Traditional / cultural framing
- Focus and attentionTraditional· Traditional / cultural framing
Geographic occurrence
Myanmar
Common (expected wild occurrence in the region)
Japan
Common (expected wild occurrence in the region)
Brazil
Common (expected wild occurrence in the region)
Mexico
Common (expected wild occurrence in the region)
India
Common (expected wild occurrence in the region)
Indonesia
Common (expected wild occurrence in the region)
Thailand
Common (expected wild occurrence in the region)
Viet Nam
Common (expected wild occurrence in the region)
Harvest
- LeafApril–May
jaro
Region: JapanNotes: The first spring picking (ichibancha in Japan, first flush in India) — the terminal bud and two youngest leaves — gives the finest tea; further pickings follow in summer. Green tea is made by heating the leaf quickly to stop oxidation.
Storage
- Airtight storage(Leaf)
Green tea keeps 6–12 months, black and oolong 2 years, in an opaque airtight caddy away from odours; an opened packet of green tea fades fast.
- Light:
- Light destroys aroma and colour — never in glass on a shelf.
- Moisture:
- Leaf is hygroscopic and picks up odours (spices, coffee) — give it its own caddy.
Processing methods on this herb card
Infusion or brief extraction in hot water; usually without long boiling.
Full method description (from the catalogue)
In the narrow sense, "tea" often means an infusion: you pour water just off the boil over the dried plant matter and let it steep for a few minutes. Temperature, steep time, and the herb-to-water ratio change both flavour and what dissolves into the liquid.
Compared with a decoction, heat exposure is shorter and gentler; tender leaves and flowers are often better as an infusion than with prolonged simmering. For each herb, always follow the plant card for suitable plant part, preparation, and safety notes — general rules never replace species-level judgement.
Traditional context for this method: yes·Scientific context for this method: yes
Finely ground dried herb; dosing and solubility depend on species.
Full method description (from the catalogue)
Powder increases surface area for liquids or food. Home milling needs a clean grinder and control of fineness; very fine powder may clog tea filters.
Store airtight against moisture and pests.
Traditional context for this method: yes·Scientific context for this method: no
Powdered leaf (matcha) is swallowed whole, so the dose of caffeine and catechins is higher than from an infusion.
Cooking, baking, seasoning as food — general category without therapeutic claims.
Full method description (from the catalogue)
Culinary use covers herbs as ingredients in dishes, drinks, or spice mixes. This overview does not evaluate medicinal effects — only reminds you about species intent, allergies, and heat treatment where needed (e.g. some fruits or plant parts).
Combining with alcohol, sugar, or long cooking changes outcomes; verify culinary sources.
Traditional context for this method: yes·Scientific context for this method: no
Traditional / spiritual use
Kept separate from science — entries are cultural or symbolic, not medical advice.
Chanoyu — the way of tea
General
Spiritual usePsychosomatic interpretationsRitualSymbolismThe Japanese tea ceremony (chanoyu, chadō) grew out of Zen monastic practice in the 15th–16th centuries; master Sen no Rikyū built it around harmony, respect, purity and tranquillity (wa, kei, sei, jaku). Preparing and serving tea is meditation and hospitality here, not treatment. A record of cultural and spiritual tradition.
- Form:
- obřadní příprava (čanoju), meditační praxe
- Claim strength:
- Tradition
- Source note:
- Japanese tea tradition (chadō); Sen no Rikyū, 16th century; Okakura Kakuzō, The Book of Tea (1906).
Scientific notes
Each claim lists a study type and a source (URL or DOI) where available. Dose notes from the literature are informational only.
How to read evidence strength and study type labels
Labels summarise how the catalogue entry is tagged — they are not a medical verdict on efficacy. For every row, read the summary, limitations and source link.
Evidence strength
- Evidence level not specified
- The author did not grade the record; judge from the summary, limitations and source link.
- Narrative / orientational literature
- Descriptive or expert literature without controlled group comparison — context rather than proof of effect.
- Weak evidence
- Study or conclusion with major methodological limits; treat only as a pointer for further reading.
- Preliminary findings
- First or smaller studies — interesting direction, not the final word on efficacy or safety.
- Moderate strength of evidence
- Moderate strength by study design; sample and context limits still apply.
- Stronger evidence
- Stronger design or consistency of results within the study's stated limits.
- Review article
- A review summarises multiple sources; quality depends on review method and field.
Study type
- Narrative / expert text
- Expert text or overview without a classical study design.
- In vitro study
- Cell culture or test-tube experiment — does not show an effect in the body.
- Animal study
- Animal model — transfer to humans is not automatic.
- Observational study
- Observing groups without random treatment assignment; confounding is possible.
- Clinical trial
- Human clinical trial; sample size and control group matter.
- Randomised controlled trial
- Randomised controlled trials are among the stronger designs when well conducted.
- Review study
- A review aggregates multiple papers — quality depends on selection rules.
- Systematic review
- Systematic review with explicit search and selection methodology.
- Meta-analysis
- Statistical pooling of studies; outcome depends on input data and heterogeneity.
- Regulatory assessment / monograph (EMA, WHO…)
- Regulatory body summary for a herbal product — different context from a single RCT; often about products, not home tea.
- Expert monograph (herbal preparations)
- Structured literature summary for a plant or drug — quality depends on author and edition year.
The HMPC accepted, on the basis of long-standing use, non-fermented (green) tea leaf as a traditional preparation for relief of fatigue and sensation of weakness in adults.
Review articleRegulatory assessment / monograph (EMA, WHO…)Year: 2013Limitations: Traditional use; the effect is explained mainly by caffeine. The monograph covers tea leaf and infusion, not concentrated extracts.
EMA Committee on Herbal Medicinal Products (HMPC)
European Union herbal monograph on Camellia sinensis (L.) Kuntze, non fermentatum folium
EFSA assessed the safety of green tea catechins: traditionally prepared infusion is safe, whereas food supplements providing ≥ 800 mg EGCG a day were associated with raised liver enzymes and reported cases of liver injury.
Review articleRegulatory assessment / monograph (EMA, WHO…)Year: 2018Limitations: A safety, not efficacy, assessment. Average EGCG intake from infusion is estimated at tens to low hundreds of mg a day; the risk concerns concentrated extracts.
EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS) — EFSA Journal
Images
The main photo is in the card header. More images will appear here when available.
Safety
What the warning types mean
The type on each warning helps group themes — it does not replace the separate severity badge.
- Internal use
- Risks from swallowing, extracts, duration of use or concentration for internal use.
- Interactions / medicines
- Possible effect on medicines or concurrent treatment — check sources and a professional.
- Raw plant parts
- Raw, unripe or poorly prepared plant parts can be dangerous.
- Toxins and regulation
- Toxic constituents or regulated compounds (e.g. in distillates).
- Contact with the plant
- Skin or mucosa irritation from contact with fresh plant or sap.
- Allergy
- Allergic reactions, often linked to family sensitisation.
- Harvesting and contamination
- Contamination, species mix-ups or harvesting from unsuitable places.
- Concentrated extracts and liver enzymesModerate severityInternal use
According to the EFSA opinion (2018), food supplements providing ≥ 800 mg EGCG a day were associated with raised liver enzymes and reported liver injury; no such risk was found for traditionally prepared infusion. 'Slimming' extract supplements are not the same as a cup of tea.