Please wait while we load the content...
L-theanine is a naturally occurring amino acid found primarily in green tea that crosses the blood-brain barrier to modulate neurotransmitter activity. It is used to promote relaxation, reduce stress, and support cognitive function without causing sedation or impairment.
Sources: Health Canada LNHPD View full source list →
Sources: Health Canada LNHPD View full source list →
Sources: Health Canada LNHPD View full source list →
This ingredient appears in licensed Canadian natural health products in Health Canada's LNHPD.
Health Canada licensing applies to specific products and is not a general endorsement of this supplement for every person or use.
Biomedical literature indexed in PubMed (NCBI) for this ingredient. Study counts reflect a keyword search, not an efficacy verdict.
PubMed counts reflect a keyword search of the biomedical literature, not a curated efficacy verdict; results can include studies with mixed or negative findings.
This ingredient appears in supplement product labels in the NIH Dietary Supplement Label Database.
NIH DSLD reflects supplement product labels marketed in the US; a match indicates market presence, not a safety or efficacy endorsement.
Western Herbal View
Derived from current regulatory records and authoritative western-source citations. Shown separately from TCM and Ayurveda profiles.
(Used as a) sleep aid (to help promote sleep). Helps (to) prevent and/or reduce the effects of jet lag/minimize jet lag (e.g. daytime fatigue, sleep disturbance) (for people/if travelling by plane easterly across two or more time zones/flying east over two or more time zones) Helps (to) re-set the body’s sleep-wake cycle (aspect of the circadian rhythm). Helps (to) speed up/reduce the time it takes to fall asleep (sleep onset latency aspect of sleep quality) in people who fall asleep slowly/with delayed sleep phase disorder. Helps increase the total sleep time (aspect of sleep quality) in people suffering from sleep restriction or altered sleep schedule (e.g. shift-work and jet lag). Helps to temporarily promote relaxation.
Purpose listed on matched licensed products
Helps to temporarily promote relaxation. A factor in normal growth and development. A factor in the maintenance of good health. Contributes to maintaining general health. For maintaining general health. Helps in energy metabolism/(and) tissue formation. Helps to maintain/support normal electrolyte balance. Helps to maintain/support normal muscle function. Maintains/supports good health. Mineral supplement. Source of/Provides (an) electrolyte(s) for the maintenance of good health. Source of/Provides (an) electrolyte(s). Used in Herbal Medicine as a sleep aid (during times of mental stress). Used in Herbal Medicine to help relieve restlessness and/or nervousness (calmative).
Purpose listed on matched licensed products
Formulated with Chasteberry extract, clinically proven to help reduce the symptoms of PMS (Pre Menstrual Syndrome) such as mood changes and irritability; clinically showen to help reduce sweet or salt cravings. Includes all-natural l-theanine which helps to provide a temporary feeling of relaxation.
Purpose listed on matched licensed products
Health Canada LNHPD
Health Canada LNHPD
Health Canada LNHPD
Health Canada LNHPD
Health Canada LNHPD
Health Canada licensing applies to specific products and is not a general endorsement of this supplement for every person or use.
Continue with evidence-based reading for safer supplement decisions.
Sleep Support
The best sleep supplement is usually the one that fits the real problem, not the one with the loudest promise on the label.
Read guide →Sleep Support
L-theanine makes more sense when the problem is a busy mind at night, not when you are looking for a heavy sedative effect.
Read guide →Safety And Interactions
SSRIs do not make every supplement off-limits, but they do make casual experimentation a much worse idea.
Read guide →Matched ingredient: L-Theanine. 1763 licensed product records.
21 indexed studies. 5 top citations linked.
Matched group: Theanine. 2,031 products on the US market.
No NIH DSLD reference links recorded yet.
Disclaimer: This information is for educational purposes only and should not replace professional medical advice. Always consult with a healthcare provider before starting any new supplement regimen.