From MEpedia, a crowd-sourced encyclopedia of ME and CFS science and history

Theanine or L-theanine, also known as boletus badius, camellia sinensis, gamma-ethylamino-L-glutamic acid or suntheanine, is an amino acid found in green tea that is sometimes taken as a herbal or alternative medicine.[1][2]

Uses[edit | edit source]

Theanine is has suggested for:

Dosage[edit | edit source]

Doses used in short term clinical trials include:

  • Anxiolytic / anxiety - 200 - 250mg in a single dose
  • Cognitive performance and mental alertness - 97 - 100mg, taken with caffeine
  • Psychiatric symptoms - 240 to 400mg daily, in divided doses[2]

Risks and side effects[edit | edit source]

Headache, dizziness and gastrointestinal symptoms have been reported.[2]

Availability[edit | edit source]

Theanine is inexpensive and available over the counter.[1]

Evidence[edit | edit source]

Evidence is limited for most suggested uses and some trials have reported no benefits or mixed results.[1]

ME/CFS[edit | edit source]

Learn more[edit | edit source]

See also[edit | edit source]

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 1.4 1.5 "L-Theanine". Memorial Sloan Kettering Cancer Center. Retrieved September 28, 2020.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 "L-Theanine Uses, Benefits & Dosage - Herbal Database". Retrieved September 28, 2020.
  3. Park, Sang-Ki; Jung, In-Chul; Lee, Won Kyung; Lee, Young Sun; Park, Hyoung Kook; Go, Hyo Jin; Kim, Kiseong; Lim, Nam Kyoo; Hong, Jin Tae (April 2011). "A combination of green tea extract and l-theanine improves memory and attention in subjects with mild cognitive impairment: a double-blind placebo-controlled study". Journal of Medicinal Food. 14 (4): 334–343. doi:10.1089/jmf.2009.1374. ISSN 1557-7600. PMID 21303262.