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Sleep
Published in Carolyn Torkelson, Catherine Marienau, Beyond Menopause, 2023
Carolyn Torkelson, Catherine Marienau
L-theanine is a compound found naturally in the tea plant (Camellia sinensis). It is thought to promote relaxation and facilitate sleep by contributing to a number of changes in the brain. It boosts levels of neurotransmitters like GABA (gamma-aminobutyric acid), serotonin, and dopamine, and it increases alpha brain wave activity that induces relaxation. Research shows that L-theanine may improve quality of sleep, not by acting as a sedative but by lowering anxiety and promoting relaxation. The recommended dose is 100–400 mg, taken 1–2 hours before bedtime.
Camellia sinensis
Published in Mehwish Iqbal, Complementary and Alternative Medicinal Approaches for Enhancing Immunity, 2023
In recent times, researchers have associated L-theanine with the emotional state of relaxation reported by those who consume green tea. Investigational research projects have also revealed that L-theanine seems to refute particular effects of caffeine. L-theanine eases the origination of α-waves in the brain assumed to be related to an alert yet relaxed mental state. A scientific study on L-theanine employing young females as research participants revealed that L-theanine appeared to have the highest impact on the generation of α-waves among those females who had been classified as subjects of raised anxiety (Talbott, 2007). Theanine is considered to decrease levels of cortisol in the period of stress. This organic relaxant functions to reduce worry, stress and apprehension, permitting the nervous system to concentrate and focus better (Cooper, 2012).
Solving pet problems
Published in Clive R. Hollin, An Introduction to Human–Animal Relationships, 2021
Michelazzi et al. (2015) used the drug l-Theanine in treating 20 dogs with a noise phobia. l-Theanine is an amino acid present in tea leaves and is commercially available, for people as well as animals, as an aid to relaxation with the benefit of not causing drowsiness. The dogs were divided into two groups: the drug was administered to ten dogs but not to the ten dogs in the control group. All 20 dog owners were given identical instructions on managing the dog's behaviour such as ignoring phobic behaviours and demands for attention while rewarding relaxed behaviours. This study has a strong design as it allows inferences to be drawn about the role of the behavioural component. The results showed an improvement in the phobic behaviours of both the treatment and control groups. Michelazzi et al. reach the view that behaviour management “Is to be considered essential for the treatment of noise phobias” (p. 57).
L-theanine improves neurophysiological measures of attention in a dose-dependent manner: a double-blind, placebo-controlled, crossover study
Published in Nutritional Neuroscience, 2022
Tharaka L. Dassanayake, Chanaka N. Kahathuduwa, Vajira S. Weerasinghe
L-theanine is a non-protein-forming amino acid structurally similar to glutamic acid. Naturally occurring in an edible form almost exclusively in tea (Camellia sinensis), the amount of L-theanine in drinking tea varies with the type and the brewing time: one cup of black tea contains 5–24 mg of L-theanine [1–3]. In rats, L-theanine peaks in plasma around 30 min after oral administration [4], crosses the blood–brain barrier [5], and is completely eliminated from plasma and the brain in 24 h [6]. In humans, peak plasma concentration of L-theanine occurs 45–50 min following ingestion, and the substance is completely cleared of plasma within 24 h [7]. Resting-state α-wave activity increases in electroencephalography (EEG) around 40 min after ingestion of 200 mg of L-theanine, indicating that theanine reaches the brain around that time in humans [8,9]. Animal models suggest L-theanine, a low-affinity glutamate receptor antagonist, binds NMDA receptors and exert a neuroprotective effect against excitotoxic neural damage [10,11]. Animal studies also show that administration of L-theanine cause acute changes of dopamine (in striatum), serotonin (in striatum, hippocampus and hypothalamus) and GABA levels [12–15]. L-theanine has been found to be safe to humans in high doses given up to several weeks [16,17].
An Examination of a Novel Weight Loss Supplement on Anthropometry and Indices of Cardiovascular Disease Risk
Published in Journal of Dietary Supplements, 2021
Ryan J. Sowinski, Tyler J. Grubic, Ryan L. Dalton, Jessica Schlaffer, Aimee G. Reyes-Elrod, Victoria M. Jenkins, Susannah Williamson, Christopher Rasmussen, Peter S. Murano, Conrad P. Earnest, Richard B. Kreider
Ashwagandha, in ayurvedic medicine, is purported to be a natural sleep aid (Raut et al. 2012), and theanine has been shown to improve sleep quality with administration of 400 mg/d (Lyon et al. 2011). According to a review by Juneja et al. (Juneja 1999; Haskell et al. 2008; Einother et al. 2010; Foxe et al. 2012), theanine is reported to have various cognition-related effects including relaxing effects with as little as a one-time dose of 50 mg. For context, the current study’s DG treatment ingested 100 mg of theanine daily, while the DG + C treatment did not include theanine in the ingredient panel. The DG treatment group reported falling asleep between 5 and 6 minutes faster by weeks 8 and 12, with slightly more ease, and fewer interruptions such as waking to use the bathroom, in comparison to the DG + C treatment that reported increased bathroom use. As well, participants in the DG + C treatment reported taking longer to fall asleep than those in placebo treatment on average. Arguably, these outcomes could be the result of simply consuming caffeine, of which DG + C ingested around 400 mg/d. Nevertheless, ingestion of the supplements studied appeared to be well tolerated but did not result in significant improvements in glucose, cholesterol, or low-density lipoprotein cholesterol when administered to overweight and obese individuals following their normal diet and activity levels.
GABA and l -theanine mixture decreases sleep latency and improves NREM sleep
Published in Pharmaceutical Biology, 2019
Suhyeon Kim, Kyungae Jo, Ki-Bae Hong, Sung Hee Han, Hyung Joo Suh
γ-Glutamylethylamine, also known as l-theanine, and γ-aminobutyric acid (GABA) are known agents for improving sleep disturbances (Khan et al. 2018). GABA is a non-proteinogenic amino acid and is the main inhibitory neurotransmitter in the mammalian brain. Hence GABAA receptors are a primary target in the search for natural anxiolytic compounds or sedatives (Khom et al. 2007; Trauner et al. 2008). There is an increasing interest in investigating the effect of GABA-mediated inhibitory neurotransmission, in respect to its potential benefit on counteracting sleep disruption caused by various conditions, such as stress, diseases and caffeine intake, etc. (Wong et al. 2003). Therefore, GABA is widely used in functional food and pharmaceutical industries, and various researches have been investigated for biosynthesis and their efficacy as metabolites of plants and microorganisms produced by the decarboxylation of glutamic acid (Coda et al. 2010; Dhakal et al. 2012; Yang et al. 2018) l-Theanine, an amino acid exclusively found in tea leaves, composes only 1–2% (w/w) of the weight of dried tea leaves (Graham 1992) and is chemically or biologically synthesized for use as an active ingredient that induces sedation (Juneja et al. 1999; Yan et al. 2003). There are several reports indicating that l-theanine exerts neuroprotective effects (Kim et al. 2009), modulates neurotransmitter activity (Kakuda 2011) and reduces psychological stress (Kimura et al. 2007) and sleep disturbances (Jang et al. 2012). Nathan et al. (2006) also reported that l-theanine intake increases serotonin, dopamine and GABA levels in the brain.