Theanine
Summary of Theanine
Primary Information, Benefits, Effects, and Important Facts
L-Theanine is an amino acid that is not common in the diet (not one of the essential amino acids or even one of the common nonessential amino acids), and is deemed a nondietary amino acid similar to L-Ornithine or L-Citrulline. L-Theanine has structural similarity to glutamine and both neurotransmitters that are produced from it (GABA and glutamate) and is known to reach the brain and act in the brain following oral ingestion.
The properties of L-theanine can be summed up as being a relaxing agent without sedation (relative to something like lemon balm which relaxes but may also sedate), and is also implicated in reducing the perception of stress and slightly improving attention. While L-theanine does not appear to induce sleep, it may (quite weakly) help with sleep although its potency suggests it may not be a good first line treatment for this.
Interestingly, the relaxing and attention promoting properties of L-theanine coupled with the lack of sedation may have its most significant supplemental role in attenuating the 'edge' of many stimulants. A combination of L-Theanine with caffeine (200mg each) is noted to be synergistic in promoting cognition and attention.
L-Theanine, for the most part, is a relaxing but not sedating amino acid that is synergistic with stimulants such as caffeine as it can 'take the edge off'. It is effective by itself in the standard supplemental dosages as well, and although it can be attained via a diet high in green tea ingestion that is the only dietary source of L-Theanine
There are some health benefits associated with green and black tea ingestion that are thought to be more reflective of the Theanine content rather than the green tea catechins or the theaflavins, and this is thought to be related to cardiovascular health (as L-Theanine positively regulates nitric oxide) and some cognitive benefits.
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L-Theanine tends to be taken in the dosage of 100-200mg, usually alongside caffeine
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Human Effect Matrix
The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what effects theanine has on your body, and how strong these effects are.
| Grade | Level of Evidence [show legend] |
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Robust research conducted with repeated double-blind clinical trials |
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Multiple studies where at least two are double-blind and placebo controlled |
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Single double-blind study or multiple cohort studies |
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Uncontrolled or observational studies only |
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Level of Evidence
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The amount of high quality evidence. The more
evidence, the more we can trust the results.
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Outcome |
Magnitude of effect
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The direction and size of the supplement's impact on
each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
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Consistency of research results
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Scientific research does not always agree. HIGH or
VERY HIGH means that most of the scientific research agrees.
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Notes |
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Notable
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Very High See all 3 studies |
A notable increase in relaxation (usually without sedation) appears to occur, as assessed by neural measurements (such as alpha-waves) or self-report surveys. Occurs within 30 minutes to an hour
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Minor
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Moderate See all 5 studies |
Possible anxiety reducing effects, although anticipatory anxiety appears to be unaffected.
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Notable
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- See study |
A single study that used 200 mg of Suntheanine® observed a notable improvement in attentional task performance in subjects with high anxiety, whereas subjects with low anxiety didn't see a notable improvement.
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Minor
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- See study |
Sleep quality has been noted to improve in persons with hyperactivity during sleep (such as ADHD). Sleep duration and latency do not appear to be affected
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Minor
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- See study |
Activation and anxiety symptoms of schizophrenia appear to be reduced with high dose (400mg) Theanine
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- | - See 2 studies |
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- | - See study |
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- | - See study |
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- | - See study |
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- | - See study |
No significant influence on subjective well being and mood state per se
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- | - See study |
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- | - See study |
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Things to Note
Is a Form Of
Primary Function:
Also Known As
L-Theanine, 5-N-Ethyl-Glutamine, γ-glutamylethylamide
Goes Well With
Caffeine (attention promotion)
Theanine is relaxing, but does not appear to induce sedation (cause sleep)
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