Tea
Chinese chá, Amoy te; thea
- Known today as
- The dried leaves of Camellia sinensis; a ship of the Dutch East India Company brought the first green tea to Amsterdam from China early in the seventeenth century.
- Kind
- Food & Drink, in 1 older authority
- Constituents
- caffeine, L-theanine, epigallocatechin gallate
- Earliest authority here
- Thomas Garway
- In other databases
- GBIF search · Wikidata search
Revised October 3, 2026: Checked against its sources, each read in full, in part, or in its abstract. Version 1, first published September 30, 2026.
Tea: what was it used for?
A remedy before it was a pleasure: for headache, drowsiness, the stone, and to help digestion.
Tea: how is it taken as a tea?
The leaf under boiling water: rarely used as a medicine, Grieve says, but the infusion is useful to relieve neuralgic headaches.
All the herbal teas of the database. Historical directions, not medical advice.
Tea: what does modern science say?
Its caffeine is the stimulant; the European Food Safety Authority found too little evidence that theanine improves cognitive function.
Pharmacognosy & Toxicology
- Constituents
- caffeine ChEMBL30–90 mg a cup
- L-theanine ChEMBL
- epigallocatechin gallate ChEMBLEGCG, in green tea
- Mechanism
- Caffeine, some 30 to 90 mg a cup, is the stimulant; claims that theanine improves cognition or sleep were not upheld by the European Food Safety Authority in 2011, and the catechins are under study.
- Toxic dose
- Green-tea extracts taken as food supplements at 800 mg EGCG a day or more raised liver enzymes in trials; rare cases of liver injury have followed even the infusion.
- Standing
- A food; in 2018 the European Food Safety Authority found that 800 mg of EGCG a day or more, taken as a supplement, raised markers of liver damage.
- European Food Safety Authority (2018). “Scientific opinion on the safety of green tea catechins.” EFSA Journal 16. Read in full · the text read
Constituent names open the compound’s record at PubChem, and “ChEMBL” beside a name opens its record at ChEMBL, the European Bioinformatics Institute’s database of bioactive molecules. Where a mechanism line was checked against ChEMBL (ChEMBL 37, read 1 October 2026), the check is shown with the measured value and its source paper, or says plainly that nothing has been measured. Doses are as the references give them, for description only; this is not medical advice. Each source carries the result of its check against Crossref, PubMed, or the authority’s page: see Verification.
Tea: what lore surrounds it?
The Dutch physician Cornelis Bontekoe made his reputation with a treatise advocating tea-drinking, which appeared in 1678.
Tea: what did the older authorities say?
- Thomas Garway
- The London merchant advertised it in a broadside of 1660 as good for nearly every complaint.
Sources
- Garway, T. (1660). An Exact Description of the Growth, Quality, and Vertues of the Leaf Tea. Read in full · the text read
- Grieve, M. A Modern Herbal, “Tea.” As published on botanical.com.
- “History of tea.” Wikipedia (read 2 October 2026). Read in part · the text read
- “Tea.” Wikipedia (read 2 October 2026). Read in part · the text read
- “Theanine.” Wikipedia (read 2 October 2026). Read in full · the text read
- “Cornelis Bontekoe.” Wikipedia (read 2 October 2026). Read in full · the text read
- “Epigallocatechin gallate.” Wikipedia (read 2 October 2026). Read in part · the text read
- Text Creation Partnership. TCP catalogue (TCP.csv), github.com/textcreationpartnership. Read in part · the text read
Verification
- Checked
- October 1, 2026, and October 3, 2026
- Passes
- Every sentence read against its sources, in the pass over the remaining 343 entries
- The Standing line checked against the authority it names (EMA, WHO, FDA, CITES, Commission E)
- Every dated or regulatory claim checked by category across the database
- Every source read, in full, in part, or in its abstract, and every sentence checked against what was read (October 3, 2026)
- Sources
- 9 cited: 4 read in full, 4 read in part, 1 not yet checked.
- Corrections
- None were needed.
What was checked, how, and what was found is set out on the Verification page. A checked source is one whose record was found; it does not make the entry medical advice.
Cite This Entry
Version 1 · first published September 30, 2026 · last revised October 3, 2026
- Chicago
“Tea.” In Materia Medica, edited by B. C. P. Statema. Version 1. The Thinking Press, 2026–. Last modified October 3, 2026. https://thethinkingpress.org/materia-medica/tea.
- MLA
“Tea.” Materia Medica, edited by B. C. P. Statema, version 1, The Thinking Press, 3 Oct. 2026, thethinkingpress.org/materia-medica/tea. Accessed 8 Oct. 2026.
- APA
Tea. (2026, October 3). In B. C. P. Statema (Ed.), Materia medica (Version 1). The Thinking Press. Retrieved October 8, 2026, from https://thethinkingpress.org/materia-medica/tea
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See Also
Sharing caffeine
Drawing on the same sources: Grieve
Nearby in the alphabet
Teasel (Dipsacus fullonum) · Teonanácatl (Small brown mushrooms that stain blue when bruised) · Tamarind (The pod pulp of Tamarindus indica) · Terra sigillata (A clay dug on the island of Lemnos and stamped with a seal) · Sweet woodruff · Tetragrammaton (not pronounced in Jewish practice) · Sweet flag (Acorus calamus)
Historical description, not medical advice.