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 September 28, 2020.
- "L-Theanine Uses, Benefits & Dosage - Drugs.com Herbal Database". Drugs.com. Retrieved September 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 a treatment, whether in a clinical trial or licensed treatment. May be minor or serious.