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.
Uses[edit | edit source]
Theanine is has suggested for:
- Brain fog symptoms (cognitive impairment), e.g. to improve concentration mental alertness, and memory, particularly in combination with green tea extract or caffeine
- Improving response to conventional cancer treatment or reducing cancer treatment side effects
- Immune system support
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
Risks and side effects[edit | edit source]
Headache, dizziness and gastrointestinal symptoms have been reported.
Availability[edit | edit source]
Theanine is inexpensive and available over the counter.
Evidence[edit | edit source]
Evidence is limited for most suggested uses and some trials have reported no benefits or mixed results.
ME/CFS[edit | edit source]
Learn more[edit | edit source]
See also[edit | edit source]
References[edit | edit source]
- "L-Theanine". Memorial Sloan Kettering Cancer Center. Retrieved Sep 28, 2020.
- "L-Theanine Uses, Benefits & Dosage - Drugs.com Herbal Database". Drugs.com. Retrieved Sep 28, 2020.
- 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.
glutamate (Glu) - Glutamate is one of the amino acids used by the body to make proteins. It is a salt or ester of glutamic acid, and the terms glutamate and glutamic acid are often used interchangeably. It also functions as the principal excitatory neurotransmitter in the brain.
adverse reaction - Any unintended or unwanted response to the treatment under investigation in a clinical trial.