$58.69 $0.97 per serving
Product analysis
200 mg of Zen may help with relaxation and winding down, with the clearest support coming from theanine.
AI assessment of the formula, label and price. How scoring works
Nutrient Quality20
The ingredient forms are unspecified, making their quality harder to judge. Ingredient names alone do not describe the preparations used.
Ingredient Transparency63
Both ingredient amounts are disclosed, allowing a clear serving comparison. Their forms are omitted, leaving the preparations less clearly described.
Value For Money46
Value is middling for theanine and less attractive for GABA. The serving cost therefore gives only a modest price case for the combination.
Customer Satisfaction78
Customer ratings are very positive across a substantial amount of feedback. That gives a broad satisfaction picture without proving a calming or sleep benefit.
Product Focus76
Relaxation is the clearest purpose, with possible help for winding down and some sleep-quality measures. Attention findings are limited or mixed, and the combination does not establish broad memory or productivity improvements.
- Format
Capsule - Container
- 120 Capsule(s)
- Per serving
- $0.97
- Customer rating
- 4.7 · 746 ratings
Goals
Impact
Highest effect
GABA · 550 mgTheanine · 200 mg
Impact
Highest effect
Theanine · 200 mg
Impact
High effect
Impact
Moderate effect
Impact
High effect
Theanine · 200 mg
Impact
High effect
Theanine · 200 mg
Impact
High effect
Theanine · 200 mg
Ingredients
| Ingredient | Amount per serving | Score |
|---|---|---|
GABA | 550 mg | |
L-Theanine | 200 mg |
Theanine · 200 mg OverallScore90
200 mg of L-theanine per serving comes at a moderate cost per 100 mg. That amount is within the range associated with relaxation and focus. A branded source is indicated, though its name is not specified.
How this ingredient is rated
Active Ingredient Quality & Bioavailability100
It uses L-theanine, the form associated with calming and focus. A branded source is indicated, though its name is not specified.
Isomer Specificity (L-Theanine)
It uses L-theanine, the form associated with calming and focus.
Branded Forms & Purity Standards
A branded source is indicated, though its name is not specified.
Dose, Safety & Label Transparency100
A serving provides 200 mg of L-theanine. That amount is within the range associated with relaxation and focus. The amount and source are individually stated.
Theanine Dosage Efficacy
A serving provides 200 mg of L-theanine. That amount is within the range associated with relaxation and focus.
Label Transparency & Blends
The amount and source are individually stated.
Value50
The cost per 100 mg of theanine is moderate.
Price per 100mg L-Theanine
The cost per 100 mg of theanine is moderate.
GABA · 550 mg OverallScore73
A serving supplies 550 mg of GABA at a high cost. The source is unspecified. The other ingredients include a flow agent, though its identity is not specified here.
How this ingredient is rated
Active Ingredient Quality & Bioavailability70
GABA is listed without a specific source or branded form.
GABA Source & Production Method
GABA is listed without a specific source or branded form.
Dose, Safety & Label Transparency93
The serving lists 550 mg of GABA. The other ingredients include a flow agent, though its identity is not specified here.
GABA Dosage Adequacy & Transparency
The serving lists 550 mg of GABA.
Label Purity & Excipient Quality
The other ingredients include a flow agent, though its identity is not specified here.
Value40
The cost per serving is high.
Price per Effective Dose
The cost per serving is high.
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Sources
Published studies used for the product analysis and the top-ranked studies for each ingredient and goal.
- Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial.
- A Randomized, Triple-Blind, Placebo-Controlled, Crossover Study to Investigate the Efficacy of a Single Dose of AlphaWave® L-Theanine on Stress in a Healthy Adult Population.
- Effects of Tea (Camellia sinensis) or its Bioactive Compounds l-Theanine or l-Theanine plus Caffeine on Cognition, Sleep, and Mood in Healthy Participants: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
- Assessing the effects of caffeine and theanine on the maintenance of vigilance during a sustained attention task.
- Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study.
- Dose-response effect of L-theanine on psychomotor speed, sustained attention, and inhibitory control: a double-blind, placebo-controlled, crossover study.
- Acute effects of theanine, caffeine and theanine-caffeine combination on attention.
- Safety and Efficacy of AlphaWave® L-Theanine Supplementation for 28 Days in Healthy Adults with Moderate Stress: A Randomized, Double-Blind, Placebo-Controlled Trial.
- Effect of L-theanine on selective attention in a traffic-related reaction task in sleep-deprived young adults: a double-blind placebo-controlled, crossover study.
- Oral intake of γ-aminobutyric acid affects mood and activities of central nervous system during stressed condition induced by mental tasks.
- Peripartum neuroactive steroid and γ-aminobutyric acid profiles in women at-risk for postpartum depression.
- The role of neurotransmitters in mediating the relationship between brain alterations and depressive symptoms in patients with inflammatory bowel disease.
- Occipital gamma-aminobutyric acid and glutamate-glutamine alterations in major depressive disorder: An mrs study and meta-analysis.
- Systematic review of gamma-aminobutyric-acid inhibitory deficits across the reproductive life cycle.
- l-theanine adjunct to sertraline for major depressive disorder: A randomized, double-blind, placebo-controlled clinical trial.
- L-theanine relieves positive, activation, and anxiety symptoms in patients with schizophrenia and schizoaffective disorder: an 8-week, randomized, double-blind, placebo-controlled, 2-center study.
- The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systematic Review.
- Comparison of the effects of two amino acids, Gamma-aminobutyric acid (GABA) and L-theanine, on sedation, anxiety, and cognition in preoperative surgical patients - A randomized controlled study.
- Anti-stress effect of theanine on students during pharmacy practice: positive correlation among salivary α-amylase activity, trait anxiety and subjective stress.
- Cognitive and affective effects of L-Theanine: a systematic review and meta-analysis of 31 randomized trials.