Nature's Trove L-Theanine 200mg 120 Vegetarian Capsules Review
Nature's Trove L-Theanine 200mg 120 Vegetarian Capsules is an individual amino acid dietary supplement designed for adult use to support relaxation, energy, vitality, and overall well-being. Each bottle contains 120 unflavored vegetarian capsules, providing a total of 120 servings per container with each capsule delivering a 200 milligram weight of L-Theanine. Found naturally in green tea, L-Theanine 200mg may promote relaxation without causing drowsiness and may also help restore a natural sense of calm. The product utilizes an osmotic release dose method and is formulated with natural ingredients under the brand philosophy of providing good health from the source. Manufactured by Nature's Trove in the USA within a GMP and NSF Certified facility, these capsules meet strict dietary and quality standards, being both Kosher Certified and Vegetarian. The product is packaged in a standard bottle container under model and manufacturer part number TRLTH120, with UPC 850056289016, Global Trade Identification Number 00850056289016, and ASIN B01D1YQBOK. For customers looking to save even more, Nature's Trove also offers a super value size option containing 365 vegetarian capsules, as well as convenient product bundles such as the Calm and Healthy Mood Stack pairing L-Theanine 200mg with 5-HTP 100mg 120 Vegetarian Capsules, and the Sleep, Calm and Stress Relief Bundle combining L-Theanine 200mg with Magtein Magnesium L-Threonate 2000mg 120 Vegetarian Capsules. In the Amazon store, this small business brand supplement is recognized as an Amazon's Choice product and holds high rankings across multiple health categories, including Sleep and Snoring Aids, Amino Acid Nutritional Supplements, and Herbal Supplements.
Study, Trial or Testing Result Summary
Members Only37 human studies · 24 improved
This product provides a full 200 mg daily dose of L-theanine. Most human studies suggest L-theanine offers modest help with stress, with 24 of 37 trials showing improvement. In a trial of 120 young adults, a single 200 mg dose lowered the rise in a saliva stress marker after a stress test compared with placebo [1]. Two four-week trials of 30 adults each, taking 200 mg or 400 mg daily, reduced stress symptoms and improved some thinking tests [2][3]. However, not all results agree. A 2026 analysis of 31 placebo-controlled trials with 1168 people found a single 200 mg dose improved attention and reaction time, but its stress-lowering effect was modest and relied on weaker studies, and anxiety results were inconsistent [4]. Furthermore, a 2022 analysis of 29 trials found that L-theanine did not reduce anxiety scores more than placebo [5]. Similarly, an eight-week trial in 46 adults with generalized anxiety disorder taking 450 to 900 mg daily found no anxiety benefit over placebo, though sleep satisfaction improved [6]. Animal and cell studies are never counted.
See all 37 studies →Hide the studies
- Across 31 placebo-controlled trials with 1168 people, a single 200 mg dose of L-theanine improved attention and reaction time, but its stress-lowering effect was modest and depended on studies with a high risk of bias, and anxiety results were inconsistent.Cognitive and affective effects of L-Theanine: a systematic review and meta-analysis of 31 randomized trials.
- In 11 placebo-controlled studies, L-theanine combined with caffeine moderately improved alertness and attention switching within 2 hours of a dose, with calmness and anxiety outcomes not clearly shown.Acute effects of tea constituents L-theanine, caffeine, and epigallocatechin gallate on cognitive function and mood: a s…
- In a network analysis of 29 trials of herbal treatments for anxiety, L-theanine did not reduce anxiety scores more than placebo.Medicinal herbs for the treatment of anxiety: A systematic review and network meta-analysis.
- A review of 22 studies found stress-related cortisol responses were most consistent with low-ratio matcha preparations and not with isolated compounds, with low-certainty evidence overall.A CE/TA-stratified systematic review and evidence map of matcha and green tea bioactives in endocrine stress regulation:…
- A review of 21 studies found green tea reduced anxiety and improved memory and attention, with the cognitive benefits seen mainly when L-theanine and caffeine were taken together.Green tea effects on cognition, mood and human brain function: A systematic review.
- A review of 9 controlled trials suggested 200 to 400 mg a day of L-theanine may reduce stress and anxiety in people under stressful conditions, though larger and longer studies are needed.The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systema…
- A review of 11 randomized trials found L-theanine reduced psychiatric symptoms more than control in people with schizophrenia, anxiety disorders and ADHD.The effects of L-theanine supplementation on the outcomes of patients with mental disorders: a systematic review.
- In 140 healthy volunteers, a daily spread with L-theanine, 5-hydroxytryptophan and GABA for 10 days improved memory, well-being and mood scores, but anxiety and depression scales did not change significantly.[Clinical evaluation of the efficacy of innovative spread of a given fatty acid composition enriched by adaptogens].
- In 120 healthy young adults, a single 200 mg dose of L-theanine, with or without arginine, lowered the rise in a stress marker in saliva after a stress test compared with placebo.Effect of Combined Ingestion of L-Theanine and L-Arginine for Short-Term Psychological Stress in Young Adults: A Randomi…
- In 103 healthy active adults, an evening blend containing 200 mg L-theanine, magnesium L-threonate and apigenin taken for two weeks did not clearly improve stress; only the morning ashwagandha and rhodiola group improved on stress, sleep and mood.Modulating stress and sleep through a multi-compound dietary supplement: a randomized, double-blind, placebo-controlled …
- In 100 chronically stressed healthy adults, a combination of magnesium, B vitamins, rhodiola and green tea with L-theanine taken for 28 days lowered stress scores more than placebo, with benefits still seen at day 56.Effect of a Combination of Magnesium, B Vitamins, Rhodiola, and Green Tea (L-Theanine) on Chronically Stressed Healthy I…
- In 80 young adults, a single 200 mg dose of L-theanine before a virtual reality active shooter drill and mental challenge did not change saliva stress markers, heart rate or anxiety scores compared with placebo.Impact of L-theanine and L-tyrosine on markers of stress and cognitive performance in response to a virtual reality base…
- In 60 people with schizophrenia or schizoaffective disorder taking antipsychotics, 400 mg daily of theanine for 8 weeks reduced anxiety and positive symptoms more than placebo, and it was well tolerated.L-theanine relieves positive, activation, and anxiety symptoms in patients with schizophrenia and schizoaffective disord…
- In 48 healthy adults, a single 200 mg dose of theanine did not significantly change mood, anxiety or alertness compared with placebo, though it did lower the blood pressure rise caused by caffeine and slowed reaction time on one task.Time for tea: mood, blood pressure and cognitive performance effects of caffeine and theanine administered alone and tog…
- In 46 adults with generalized anxiety disorder taking meds, 450-900 mg of L-theanine daily for 8 weeks did not reduce anxiety more than placebo, though it improved sleep satisfaction scores.L-theanine in the adjunctive treatment of generalized anxiety disorder: A double-blind, randomised, placebo-controlled t…
- In 40 people with schizophrenia or schizoaffective disorder taking 400 mg daily of theanine for 8 weeks, changes in blood BDNF and cortisol-to-DHEAS ratio were linked to symptom improvement, though this was an association analysis.Serum levels of brain-derived neurotrophic factor and cortisol to sulfate of dehydroepiandrosterone molar ratio associat…
- In 40 people with schizophrenia taking antipsychotics, 400 mg daily of L-theanine plus 50 mg pregnenolone for 8 weeks reduced negative symptoms and anxiety compared with placebo.Add-On Pregnenolone with L-Theanine to Antipsychotic Therapy Relieves Negative and Anxiety Symptoms of Schizophrenia: An…
- In 39 adults, drinking test matcha with a high theanine content lowered anxiety compared with placebo matcha, and the study notes that caffeine can counteract theanine's effect.Stress-Reducing Function of Matcha Green Tea in Animal Experiments and Clinical Trials.
- In 39 working adults with poor sleep, a 4-week RLX2 supplement containing L-theanine improved sleep quality scores compared with placebo, though the L-theanine dose was not stated.Effect of Alpha-S1-Casein Tryptic Hydrolysate and L-Theanine on Poor Sleep Quality: A Double Blind, Randomized Placebo-C…
- In 34 healthy adults aged 18-40, a single L-theanine drink reduced self-reported stress from a multitasking mental task compared with placebo, measured one hour after dosing.Anti-Stress, Behavioural and Magnetoencephalography Effects of an L-Theanine-Based Nutrient Drink: A Randomised, Double-…
- In 30 older adults with cognitive decline, two months of a combined nutraceutical containing L-theanine improved memory test scores and perceived stress compared with placebo; the L-theanine dose was not stated.Short-Term Impact of a Combined Nutraceutical on Cognitive Function, Perceived Stress and Depression in Young Elderly wi…
- In a 4-week placebo-controlled trial of 30 healthy adults taking 200 mg per day, L-theanine improved stress-related symptoms, sleep quality, and verbal fluency and executive function compared with placebo.Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized …
- In 30 healthy adults with moderate stress, 400 mg daily of theanine for 28 days reduced perceived stress and improved reaction time on a Stroop test, with some sleep changes, compared with placebo.Safety and Efficacy of AlphaWave® L-Theanine Supplementation for 28 Days in Healthy Adults with Moderate Stress: A Rando…
- In 20 pharmacy students, 200 mg of theanine twice daily during a stressful practice period lowered self-rated stress and a stress-linked salivary enzyme compared with placebo.Anti-stress effect of theanine on students during pharmacy practice: positive correlation among salivary α-amylase activ…
- In 20 pharmacy students over 10 days, drinking low-caffeine green tea providing about 15 mg of theanine daily lowered subjective stress and blunted the rise in a salivary stress marker compared with placebo tea.Anti-stress Effect of Green Tea with Lowered Caffeine on Humans: A Pilot Study.
- In 20 middle-aged adults, 7 days of low-caffeine green tea (which keeps more theanine) lowered a salivary stress marker and improved sleep quality compared with standard green tea.Reduced Stress and Improved Sleep Quality Caused by Green Tea Are Associated with a Reduced Caffeine Content.
- In 16 healthy volunteers, a single 200 mg dose of L-theanine did not reduce anticipatory anxiety under experimentally induced anxiety, though it showed some relaxing effect at rest.Read the study on PubMed (15378679) →
- In 14 adults under mental stress, L-theanine blunted the blood pressure rise in high-responders and reduced tension-anxiety mood scores compared with placebo; the dose was not stated.Effects of L-theanine or caffeine intake on changes in blood pressure under physical and psychological stresses.
- In a placebo-controlled study of 12 adults given a mental arithmetic stress task, L-theanine reduced heart rate and salivary immunoglobulin A responses to stress compared with placebo.L-Theanine reduces psychological and physiological stress responses.
- In 12 elite wrestlers, 3 mg/kg of L-theanine combined with caffeine improved performance and reduced anxiety compared with placebo, while L-theanine alone was not reported to show a clear anxiety benefit.Performance-enhancing effects of caffeine and L-Theanine among Iranian elite wrestlers: a focus on cognitive and specifi…
- In nine children with autism, a high L-theanine tea showed only sporadic improvements in balance and sleep, while a high GABA tea gave more consistent gains; the L-theanine dose was not stated.A double-blind, placebo-controlled, randomised-designed GABA tea study in children diagnosed with autism spectrum condit…
- In a crossover study of moderately stressed healthy adults, a single 200 mg dose of theanine increased frontal alpha brain wave activity and lowered salivary cortisol more than placebo after a stress task.A Randomized, Triple-Blind, Placebo-Controlled, Crossover Study to Investigate the Efficacy of a Single Dose of AlphaWav…
- In an 8-week placebo-controlled trial, a combined walnut peptide and theanine supplement improved self-reported sleep quality and sleep duration in adults with sleep disturbance; the theanine dose alone was not reported.Walnut peptide and theanine combination ameliorates sleep disorders: a multi-species study including a human trial.
- In 36 people shown stressful film clips, a single 200 mg dose of L-theanine sharpened one type of visual attention and altered another, while counteracting the effects of caffeine when taken together.Caffeine and theanine exert opposite effects on attention under emotional arousal.
- In 18 college archers given L-theanine or a placebo before a competition, the L-theanine group reported lower pre-competition anxiety and lower saliva stress markers at some time points.Effects of supplement L-theanine on cognitive anxiety, salivary alpha-amylase, and cortisol in archery competition.
- In 34 children with Tourette syndrome and anxiety, an L-theanine and vitamin B6 supplement reduced tics and anxiety more than psychoeducation alone in an open-label trial, though both groups improved and placebo-controlled trials are still needed.Use of Nutritional Supplements Based on L-Theanine and Vitamin B6 in Children with Tourette Syndrome, with Anxiety Disor…
- In an open-label study of 20 adults with major depression, 250 mg of L-theanine daily added to their medication for 8 weeks was linked to lower depression, anxiety and sleep scores and better attention and memory tests, though there was no placebo group.Effects of chronic l-theanine administration in patients with major depressive disorder: an open-label study.
Review Totals and Summary
Members Only27,939 reviews · 91% positive
Customer feedback for Nature's Trove L-Theanine 200mg 120 Vegetarian Capsules consistently highlights its efficacy in promoting relaxation and reducing feelings of stress and anxiety. Many users report that the supplement effectively helps them calm their minds, particularly before sleep, contributing to improved rest without causing morning grogginess or a "hungover" feeling, unlike some sedatives. This gentle yet effective action is a recurring positive theme, with customers appreciating that it restores a sense of calm without inducing drowsiness, allowing them to remain mentally alert and focused. Reviewers frequently praise the product for its ability to de-stress them after a busy day and help manage anxiety and irritability. Some individuals with conditions like ADHD have found it beneficial in managing stress associated with their condition. The supplement is also noted for enhancing mental focus and concentration, with some users experiencing improved productivity and the ability to complete tasks more efficiently. A notable qualitative observation is that the product "worked" for many, with sentiments like "It worked!" and "Happy with this product!" appearing frequently in reviews, indicating a tangible positive effect on their well-being. The value proposition of Nature's Trove L-Theanine is another strong point, with customers often commenting on its affordability compared to other L-Theanine supplements on the market. Many consider it a "great buy" and a "steal" for the quality and quantity provided, especially when purchasing larger counts. Some customers have also noted its effectiveness in managing blood-sugar related anxiety. Furthermore, the product has been recognized as a "Top Pick" in L-Theanine supplements by ConsumerLab.com, lending professional credibility to the positive customer experiences. A few users also mention combining it with caffeine to achieve a synergistic effect of calm focus, suggesting versatility in its application.
Biohacker Summary
Members Only0 of 10 recommend it
Our biohacker panel has not discussed this product’s ingredients yet.
RAL Summary
Members OnlyTier 4 for Stress and Calm
The studies do not show L-theanine is ineffective for stress, as 24 of 37 human studies showed improvement and the evidence is mixed rather than negative. So it is graded Tier 4, as the studies disagree.
- Emerging: not enough evidence to rank higher yet.
Where the evidence disagrees: 6 of the 37 human studies found no effect.
More Details
Members OnlyBody systems · Combine with · Possible side effects
Body systems: Nervous system
Combine with: To enhance the calming and stress-reducing effects of L-Theanine, consider combining it with Magnesium, which is crucial for nerve function and relaxation, or with Ashwagandha, an adaptogen known to help the body manage stress. For a more direct calming effect, GABA can be a good addition. If the goal is focused calm without jitters, L-Theanine is often synergistically paired with a small amount of Caffeine.
Possible side effects: No major side effects reported.
Supplement Facts
L-Theanine 200 mg
| L-Theanine | 200 mg | † |
Other ingredients: Vegetable Capsule (Cellulose), Microcrystalline Cellulose, Silicon Dioxide, Vegetable Magnesium Stearate.
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Graded November 3, 2026 by the Reverse Age Lab evidence engine, from human studies, real reviews and our biohacker panel. How we grade. Is this medical advice? No. Rala organizes the published evidence; go over any change with your doctor, especially if you take meds.
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