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Pure Tranquility Liquid

Pure Encapsulations
4.3
★ ★ ★ ★ ★
(17 ratings)
GABA 100 mg
Glycine 50 mg
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Score68
Branded theanine and GABA offer a clean liquid relaxation formula. Token glycine and very high cost limit value.
How scoring works
Quantity:116 Milliliter(s) • (29 servings)
Goals:
Stress Relief
Sleep Support

Score 68

Branded theanine and GABA offer a clean liquid relaxation formula. Token glycine and very high cost limit value.
How scoring works
$51.00($1.75 per serving)
Pure Formulas
$ 51.00
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Analysis

Suntheanine and GABA are each supplied at 100 mg, creating a concise two-pathway calming core. Liquid delivery supports flexible and easy use for people who avoid capsules.

Glycine at 50 mg is far below gram-level sleep use and adds little independent depth. GABA is clearly dosed but lacks a branded fermented source or enhanced-delivery detail.

The three-active formula avoids stimulants and is easy to understand. Only 29 servings and a high serving cost make value weak compared with simpler theanine or GABA products.

Who is it for
  • Adults seeking a liquid calming formula
  • People who value Suntheanine
  • Users who avoid capsules
Best for
  • Short-term stress relief
  • Evening relaxation
  • Flexible liquid dosing

Pros

  • Uses 100 mg Suntheanine
  • Provides 100 mg GABA
  • Simple stimulant-free formula
  • Liquid format

Cons

  • Glycine amount is tiny
  • Very high serving cost
  • Only 29 servings
  • GABA source is not premium identified

Warnings

  • Theanine and GABA may cause drowsiness
  • Alcohol or sedative medicines may increase the calming effect
  • Avoid driving until individual response is known

Nutrient quality

84 Highest impact

Branded Suntheanine supports form quality, while GABA and glycine use conventional forms. Theanine is meaningful, but GABA and glycine remain modest for standalone use.

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Ingredient transparency

81 Highest impact

Active amounts are stated and no proprietary blend hides a core dose. Missing excipient details and complete use directions leave the supplied label information incomplete.

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Customer satisfaction

53 Moderate impact

The supplied aggregate satisfaction average provides a broad signal, while the response volume determines how stable it appears. No comment-level evidence is available to assess repeated complaints or confirm intended-use experiences.

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Value for money

45 Lower impact

Quality, safety trade-offs, or serving economics materially weaken value. The focused three-active formula shows no low-value padding.

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Goals

Stress Relief
Stress Relief
Impact
Highest effect
B+ Goal FitB- Strength of SupportB CoverageA+ Formula Quality
Glycine · 50 mgGABA · 100 mgTheanine · 100 mg

Branded theanine provides direct calm-focus support, while GABA adds an inhibitory signaling pathway. The liquid format allows flexible use and each active is clearly listed.

Glycine is far below sleep-support amounts and oral GABA evidence remains less consistent because brain uptake is uncertain. The compact formula is still logically built for short-term relaxation without stimulants.

Study evidence
GABA Supportive 6 studies
Glycine Supportive 1 study
Theanine Supportive 16 studies
Sleep Support
Sleep Support
Impact
High effect
C+ Goal FitD+ Strength of SupportD+ CoverageA Formula Quality
Theanine · 100 mgGlycine · 50 mg

L-theanine and GABA target mental relaxation, while glycine adds a separate sleep-related mechanism. The concept is coherent, but the ingredient amounts are mostly modest.

Branded Suntheanine is a quality strength and GABA is clearly dosed. Glycine at 50 mg is far below the gram-level amounts used in sleep research, and oral GABA has uncertain brain availability.

Study evidence
GABA Supportive 4 studies
Glycine Supportive 3 studies
Theanine Supportive 8 studies

Ingredients

IngredientAmount per serving
GABA
100 mg
Suntheanine (L-Theanine)
 100 mg
Glycine
50 mg
Gluten Free Adults 18–50
Report overview
GABA · 100 mg OverallScore66
B- Active Ingredient Quality & BioavailabilityB+ Dose, Safety & Label TransparencyF Value

A clearly disclosed 100 mg GABA dose fits a multi-ingredient calming liquid, but the source is not identified as fermented or branded. Liquid delivery is convenient, while the lack of liposomal or sublingual detail limits confidence in enhanced absorption. The high serving cost and incomplete excipient disclosure weaken value.

View ingredientView products
Glycine · 50 mg OverallScore64
C- Active Ingredient Quality & BioavailabilityC+ Dose, Safety & Label TransparencyB- Value

The liquid includes only a small glycine amount within a calming blend. Liquid dosing is convenient for this use, but it is impractical for reaching typical high-dose glycine targets, and source purity is unverified. Branded theanine and GABA support neutral full-formula value despite very poor glycine-specific efficiency.

View ingredientView products
Loading alternative details
85 Performance

Pharma GABA 250 mg

Natural Factors Stress-Relax
Pharma GABA supplies a clearly named 200 to 250 mg form in a focused calming formula. Its formulation quality and curcumin focus compare favorably with the original, although the formula does not retain the original product’s glycine component.
83 Performance

GABA 500 mg

Swanson
A focused 500 mg GABA serving provides a clearly disclosed and practical amount of the main calming ingredient. Its formulation quality and curcumin focus compare favorably with the original, although the formula does not retain the original product’s glycine component.
83 Performance

GABA 750 mg

NOW
A focused 750 mg GABA serving provides substantially more of the main calming ingredient than the original. Its formulation quality and curcumin focus compare favorably with the original, although the formula does not retain the original product’s glycine component.
84 Budget

GABA

NOW
A focused 500 mg GABA serving provides a clearly disclosed and practical amount of the main calming ingredient. A lower serving cost improves everyday value, although the formula does not retain the original product’s glycine component.
81 Budget

GABA Powder

Source Naturals Serene Science
A focused 750 mg GABA serving provides substantially more of the main calming ingredient than the original. A lower serving cost improves everyday value, although the formula does not retain the original product’s glycine component.
83 Budget

GABA 500 mg

Nutricost
Curcumin remains the main active, but the supplied label does not clearly state its active curcuminoid yield. A lower serving cost improves everyday value, although some active-form details remain incomplete.
84 Value

GABA 500 mg

NOW
A focused 500 mg GABA serving provides a clearly disclosed and practical amount of the main calming ingredient. Useful formulation quality and efficient serving economics create a favorable quality-to-cost balance, although the formula does not retain the original product’s glycine component.
81 Value

GABA 750 mg

Source Naturals Serene Science
A focused 750 mg GABA serving provides substantially more of the main calming ingredient than the original. Useful formulation quality and efficient serving economics create a favorable quality-to-cost balance, although the formula does not retain the original product’s glycine component.
82 Value

GABA 750 mg

AN Amazing Nutrition Amazing Formulas
A focused 750 mg GABA serving provides substantially more of the main calming ingredient than the original. Useful formulation quality and efficient serving economics create a favorable quality-to-cost balance, although the formula does not retain the original product’s glycine component.
Report alternatives

Sources

Published studies used for the product analysis and the top-ranked studies for each ingredient and goal.

  1. New therapeutic strategy for amino acid medicine: glycine improves the quality of sleep.
    Bannai M; Kawai N · Journal of pharmacological sciences · 2012
    Narrative reviewSleep Support forGlycine
  2. Oral intake of γ-aminobutyric acid affects mood and activities of central nervous system during stressed condition induced by mental tasks.
    Yoto A; Murao S; Motoki M; Yokoyama Y; Horie N; Takeshima K; Masuda K; Kim M; Yokogoshi H · Amino acids · 2012
    Randomized trial63 participantsStress Relief forGABA
  3. Oral supplementation with glycine reduces oxidative stress in patients with metabolic syndrome, improving their systolic blood pressure.
    Díaz-Flores M; Cruz M; Duran-Reyes G; Munguia-Miranda C; Loza-Rodríguez H; Pulido-Casas E; Torres-Ramírez N; Gaja-Rodriguez O; Kumate J; Baiza-Gutman LA; Hernández-Saavedra D · Canadian journal of physiology and pharmacology · 2014
    Randomized trial60 participantsStress Relief forGlycine
  4. Safety and Efficacy of Gamma-Aminobutyric Acid from Fermented Rice Germ in Patients with Insomnia Symptoms: A Randomized, Double-Blind Trial.
    Byun JI; Shin YY; Chung SE; Shin WC · Journal of clinical neurology (Seoul, Korea) · 2020
    Randomized trial40 participantsSleep Support forGABA
  5. Analysis of the Effects of Known Sleep-Support Supplements in Relation to Life Habits, Sleep Conditions, and Sleep Problems.
    Imafuku F; Yamamoto K; Tanaka E; Aoki R; Nishino S · Nutrients · 2023
    Randomized trial160 participantsSleep Support forGABA
  6. Reduced γ-aminobutyric acid in occipital and anterior cingulate cortices in primary insomnia: a link to major depressive disorder?
    Plante DT; Jensen JE; Schoerning L; Winkelman JW · Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2012
    Case-control study40 participantsSleep Support forGABA
  7. GABA Supplementation, Increased Heart-Rate Variability, Emotional Response, Sleep Efficiency and Reduced Depression in Sedentary Overweight Women Undergoing Physical Exercise: Placebo-Controlled, Randomized Clinical Trial.
    Guimarães AP; Seidel H; Pires LVM; Trindade CO; Baleeiro RDS; Souza PM; Silva FGDE; Coelho DB; Becker LK; Oliveira EC · Journal of dietary supplements · 2024
    Randomized trial30 participantsSleep Support Stress Relief forGABA
  8. The effect of glycine administration on the characteristics of physiological systems in human adults: A systematic review.
    Soh J; Raventhiran S; Lee JH; Lim ZX; Goh J; Kennedy BK; Maier AB · GeroScience · 2024
    Systematic reviewSleep Support forGlycine
  9. The effects of glycine on subjective daytime performance in partially sleep-restricted healthy volunteers.
    Bannai M; Kawai N; Ono K; Nakahara K; Murakami N · Frontiers in neurology · 2012
    Clinical trial7 participantsSleep Support forGlycine
  10. Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial.
    Hidese S; Ogawa S; Ota M; Ishida I; Yasukawa Z; Ozeki M; Kunugi H · Nutrients · 2020
    Randomized trial30 participantsSleep Support forTheanine
  11. Comparison Between Efficacy of Oral Melatonin and Oral L-theanine in Improving Sleep in Cancer Patients Suffering From Insomnia: A Randomised Double-blinded Placebo-controlled Study.
    Kurdi MS; As A; Ladhad DA; Mitragotri MV; Baiju A · Indian journal of palliative care · 2024
    Randomized trial120 participantsSleep Support forTheanine
  12. The effects of L-theanine consumption on sleep outcomes: A systematic review and meta-analysis.
    Bulman A; D'Cunha NM; Marx W; Turner M; McKune A; Naumovski N · Sleep medicine reviews · 2025
    Meta-analysis897 participants19 studies pooledSleep Support forTheanine
  13. In Search of a Safe Natural Sleep Aid.
    Rao TP; Ozeki M; Juneja LR · Journal of the American College of Nutrition · 2016
    Narrative reviewSleep Support forTheanine
  14. L-theanine in the adjunctive treatment of generalized anxiety disorder: A double-blind, randomised, placebo-controlled trial.
    Sarris J; Byrne GJ; Cribb L; Oliver G; Murphy J; Macdonald P; Nazareth S; Karamacoska D; Galea S; Short A; Ee C; Birling Y; Menon R; Ng CH · Journal of psychiatric research · 2020
    Randomized trial46 participantsSleep Support forTheanine
  15. Relieving occupational fatigue by consumption of a beverage containing γ-amino butyric acid.
    Kanehira T; Nakamura Y; Nakamura K; Horie K; Horie N; Furugori K; Sauchi Y; Yokogoshi H · Journal of nutritional science and vitaminology · 2011
    Clinical trial30 participantsStress Relief forGABA
  16. Cortical gamma-aminobutyric acid and glutamate in posttraumatic stress disorder and their relationships to self-reported sleep quality.
    Meyerhoff DJ; Mon A; Metzler T; Neylan TC · Sleep · 2014
    Case-control study45 participantsStress Relief forGABA
  17. 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.
    Deshpande SS; Kurdi M; Baiju A; Athira AS; Sarasamma AG; Gangadharan AK · Journal of anaesthesiology, clinical pharmacology · 2025
    Randomized trial168 participantsStress Relief forGABA Stress Relief forTheanine
  18. Anti-Stress, Behavioural and Magnetoencephalography Effects of an L-Theanine-Based Nutrient Drink: A Randomised, Double-Blind, Placebo-Controlled, Crossover Trial.
    White DJ; de Klerk S; Woods W; Gondalia S; Noonan C; Scholey AB · Nutrients · 2016
    Randomized trial34 participantsStress Relief forTheanine
  19. 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.
    Ritsner MS; Miodownik C; Ratner Y; Shleifer T; Mar M; Pintov L; Lerner V · The Journal of clinical psychiatry · 2011
    Randomized trial60 participantsStress Relief forTheanine
  20. Safety and Efficacy of AlphaWave® L-Theanine Supplementation for 28 Days in Healthy Adults with Moderate Stress: A Randomized, Double-Blind, Placebo-Controlled Trial.
    Moulin M; Crowley DC; Xiong L; Guthrie N; Lewis ED · Neurology and therapy · 2024
    Randomized trial30 participantsStress Relief forTheanine
  21. 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.
    Evans M; McDonald AC; Xiong L; Crowley DC; Guthrie N · Neurology and therapy · 2021
    Randomized trialStress Relief forTheanine