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Pure Energy

Swanson
4.5
★ ★ ★ ★ ★
(324 ratings)
Theanine 160 mg
Caffeine 100 mg
Rhodiola
Product Image
Score83
A measured caffeine dose paired with more theanine offers useful daytime energy with a calmer profile. Rhodiola is secondary, and late dosing can still interfere with sleep.
How scoring works
Quantity:60 Capsule(s) • (30 servings)
Goals:
Mental Focus
Energy
Productivity Boost
Fitness
Cognitive Support
Brain Health
Mood Support
Weight Loss
Metabolism Boost
Stress Relief

Score 83

A measured caffeine dose paired with more theanine offers useful daytime energy with a calmer profile. Rhodiola is secondary, and late dosing can still interfere with sleep.
How scoring works
$16.09($0.53 per serving)
iHerb
$ 0.00
Amazon
$ 16.09
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Analysis

Caffeine is supplied at 100 mg, enough for noticeable alertness without entering a very-high-dose range. L-theanine at 160 mg is sensibly paired to support calmer focus and may reduce some stimulant edge.

Rhodiola rosea root extract adds 100 mg and identifies rosavins, but the marker percentage is not stated. The amount is modest for stand-alone adaptogen use, so it should be viewed as secondary to the caffeine-theanine pair.

Two capsules and reasonable value make the formula practical for daytime use. It fits energy, focus, and workout motivation better than sleep or nighttime stress support.

Who is it for
  • Adults seeking moderate daytime stimulation
  • People who prefer caffeine paired with theanine
  • Users who tolerate 100 mg caffeine
Best for
  • Daytime energy
  • Calm mental focus
  • Pre-work or pre-exercise alertness

Pros

  • Provides 100 mg caffeine
  • Pairs caffeine with 160 mg L-theanine
  • Uses Rhodiola rosea root extract
  • Clearly lists all three amounts

Cons

  • Rhodiola is modestly dosed
  • Rhodiola marker percentage is missing
  • Not appropriate for sleep support
  • Can still cause stimulant effects

Warnings

  • Caffeine may cause jitteriness, headache, faster heartbeat, or anxiety in sensitive users.
  • Late-day dosing can delay sleep even with the included theanine.
  • Count the 100 mg serving toward total daily caffeine from coffee, tea, energy drinks, and other supplements.

Nutrient quality

89 Highest impact

L-theanine and a rosavin-linked rhodiola extract support quality, though the rhodiola marker percentage is missing; caffeine and L-theanine are meaningfully dosed, while rhodiola sits at the lower end for a blend. The stimulant amount is moderate, but sensitive users may experience anxiety or sleep disruption; all three actives logically support energy with a calmer stimulant profile; the concise formula contains no obvious filler actives.

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Ingredient transparency

78 High impact

Every listed active has a specific amount; no proprietary blend hides key doses. The active ingredients are clearly named, with only the caffeine source and rhodiola standardization left incomplete; serving directions and inactive ingredients are not included in the supplied details.

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Customer satisfaction

70 High impact

The supplied aggregate average is favorable, though no individual feedback is available; the large rating sample improves confidence in the aggregate average, but no individual feedback is supplied. Detailed feedback is absent, so repeated complaints cannot be assessed; real-world fit with the intended purpose remains uncertain.

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Value for money

94 Highest impact

A concise and useful formula supports strong value; each serving provides meaningful actives at a modest cost. No low-value extras inflate the formula; the price-to-formula balance compares well within energy supplements.

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Report analysis

Goals

Mental Focus
Mental Focus
Impact
Highest effect
A+ Goal FitA Strength of SupportA CoverageA+ Formula Quality
Theanine · 160 mgCaffeine · 100 mg

Caffeine, L-theanine, and rhodiola create a well-balanced approach to alertness, calm attention, and stress resilience. The 100 mg caffeine and 160 mg theanine amounts are well matched, while rhodiola adds supportive but modest adaptogenic coverage.

All three actives are clearly disclosed and serve distinct cognitive roles without label clutter. Caffeine can still cause anxiety or sleep disruption, and rhodiola may feel activating when the product is taken late in the day.

Study evidence
Caffeine Supportive 128 studies
Rhodiola Supportive 15 studies
Theanine Supportive 19 studies
Energy
Energy
Impact
Highest effect
A Goal FitA- Strength of SupportA CoverageA+ Formula Quality
Caffeine · 100 mg

Caffeine provides direct alertness, while L-theanine may smooth the mental feel and Rhodiola rosea adds stress-related fatigue support. Their individually disclosed amounts create a well-balanced blend across acute focus and resilience.

Rhodiola lists rosavins but not salidrosides, and the caffeine source is described only as natural, which leaves some quality details uncertain. The 100 mg caffeine dose may worsen anxiety or disturb sleep, especially for sensitive users or when taken late in the day.

Study evidence
Caffeine Supportive 68 studies
Rhodiola Supportive 18 studies
Theanine Not classified

No linked studies yet.

Productivity Boost
Productivity Boost
Impact
Highest effect
A Goal FitA- Strength of SupportA- CoverageA+ Formula Quality
Theanine · 160 mgCaffeine · 100 mg

Caffeine provides acute alertness, L-theanine may smooth the subjective stimulation, and rhodiola adds fatigue-resistance support. The caffeine-theanine pairing has credible human evidence, while rhodiola evidence is useful but more variable.

The 100 mg caffeine and 160 mg theanine amounts are well balanced, although rhodiola at 100 mg is modest and incompletely standardized. Caffeine may worsen anxiety or disrupt sleep in sensitive users, especially when taken later in the day.

Study evidence
Caffeine Supportive 108 studies
Rhodiola Supportive 7 studies
Theanine Supportive 5 studies
Fitness
Fitness
Impact
Highest effect
A Goal FitB+ Strength of SupportB CoverageA+ Formula Quality
Caffeine · 100 mg

Caffeine provides direct pre-workout alertness and endurance support, while L-theanine may smooth stimulation. Rhodiola adds a plausible fatigue-resistance component for demanding sessions.

The 100 mg caffeine amount is moderate, and the 160 mg theanine amount creates a balanced stimulation profile. Rhodiola is only 100 mg and lists rosavins without a fuller standardization, so its performance contribution is less certain.

Study evidence
Caffeine Supportive 255 studies
Rhodiola Supportive 13 studies
Cognitive Support
Cognitive Support
Impact
Highest effect
A- Goal FitB+ Strength of SupportB CoverageA+ Formula Quality
Theanine · 160 mg

Caffeine, L-theanine, and Rhodiola form a practical stack for alertness, calm focus, and stress-related fatigue. The combination is better suited to near-term mental performance than long-term memory support.

The L-theanine amount is well aligned, while Rhodiola sits at the lower end and lacks complete marker details. The disclosed caffeine can cause jitteriness or sleep disruption in sensitive users, especially later in the day.

Study evidence
Rhodiola Supportive 7 studies
Theanine Supportive 25 studies
Brain Health
Brain Health
Impact
Highest effect
A- Goal FitB Strength of SupportB+ CoverageA+ Formula Quality

Caffeine, L-theanine, and rhodiola form a practical blend for alert focus and mental fatigue under pressure. Theanine is well dosed, while rhodiola is more modest and incompletely standardized.

The formula covers stimulation, calm attention, and adaptation without becoming overly broad. The 100 mg caffeine amount may cause jitteriness, palpitations, or sleep disruption in sensitive users.

Study evidence
Rhodiola Supportive 8 studies
Theanine Supportive 17 studies

Ingredients

IngredientAmount per serving
Naturally sourced Caffeine
100 mg
Rhodiola rosea root extract (Rosavins)
 100 mg
L-Theanine
160 mg
Adults 18–50
Report overview
Theanine · 160 mg OverallScore88
B+ Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyB+ Value

The clearly disclosed 160 mg L-theanine amount sits well within the preferred range. Generic sourcing lacks premium purity evidence, but the cost per active amount is competitive. The 100 mg caffeine dose may worsen anxiety or disrupt sleep in sensitive users, especially when taken late in the day.

View ingredientView products
Caffeine · 100 mg OverallScore68
D- Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyC Value

The 100 mg caffeine dose reaches the lower end of the optimal range and is clearly disclosed. A natural origin is claimed, but the botanical source and standardization are not identified, and no modified-release system is stated. Rhodiola and L-theanine have exact amounts, while the serving cost remains near the collection's typical level.

View ingredientView products
Rhodiola (Rosavins) · 100 mg OverallScore66
B Active Ingredient Quality & BioavailabilityB Dose, Safety & Label TransparencyF Value
+1

Rhodiola rosea root extract is clearly identified, but only rosavins are disclosed. The amount fits a lower-dose energy blend rather than the preferred standalone range. Added caffeine may increase stimulation and can contribute to jitteriness or sleep disruption in sensitive users.

View ingredientView products
Loading alternative details
77 Performance

Pulse Fruit Punch

Legion
A full pre-workout blend adds citrulline malate, beta-alanine, betaine, and Alpha-GPC to the caffeine-theanine base, giving it much broader exercise support. The caffeine amount is very high, so it is less suitable for stimulant-sensitive users.
68 Performance

Prolific Pre-Workout Cotton Candy

PEScience
Citrulline, betaine, taurine, citicoline, theanine, and rhodiola provide substantially more workout and cognitive depth. Label data make the split between its two caffeine entries unclear, which raises an important safety and transparency concern.
79 Performance

Cortisol Calm

Pure Encapsulations
Standardized rhodiola, ashwagandha, magnolia, and theanine offer deeper stress-focused support without caffeine. It is less suited to immediate stimulation, but it better serves users who want rhodiola and calm focus without a stimulant load.
84 Budget

L-Theanine & Caffeine

SR Sports Research
A two-to-one theanine-to-caffeine ratio supports calm alertness with fully stated amounts and favorable serving economics. The added medium-chain triglycerides are unnecessary for these actives, but the moderate stimulant dose is easier to assess than a complex blend.
84 Budget

Smart Caffeine with L-Theanine

NS Natural Stacks
The simple two-to-one theanine-to-caffeine pairing supports focused energy at favorable value. It omits rhodiola, but its green-coffee caffeine source and clear amounts make the formula straightforward to use.
83 Budget

TheanineUP Focused Energy

California Gold Nutrition
Equal amounts of theanine and coffee-fruit caffeine support alert focus at favorable serving economics. Matcha and cocoa add mild complementary stimulation, although the formula does not provide rhodiola.
82 Value

Elite

Eu Natural
A clear two-to-one theanine-to-caffeine ratio delivers a similar calm-focus effect with strong serving value. The caffeine source is unspecified and rhodiola is absent, but the concise label is easy to evaluate.
70 Value

Energy + Focus

ZHOU
Theanine and caffeine provide economical focus support, but the label lists three caffeine entries at the same amount. That ambiguity weakens safety confidence, so users should verify the total stimulant amount before choosing it.
74 Value

Hydroxycut Hardcore Elite

MuscleTech Performance Series
The formula offers low-cost stimulant support with caffeine, green coffee, and theanine. Yohimbe and the aggressive stimulant mix create greater anxiety, heart-rate, blood-pressure, and sleep trade-offs than the original.
Report alternatives

Sources

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

  1. Differential cognitive effects of energy drink ingredients: caffeine, taurine, and glucose.
    Giles GE; Mahoney CR; Brunyé TT; Gardony AL; Taylor HA; Kanarek RB · Pharmacology, biochemistry, and behavior · 2013
    Randomized trial48 participantsEnergy forCaffeine
  2. No effects of caffeine on cycling to exhaustion and perceptual responses in non-caffeine-restricted subjects.
    Weippert M; Behrens M; Schlegel M; Schröder T; Tillmann M; Rühe N; Römer R; Mau-Möller A; Bruhn S · Journal of the International Society of Sports Nutrition · 2025
    Randomized trial56 participantsEnergy forCaffeine
  3. Promising, but Not Completely Conclusive-The Effect of l-Theanine on Cognitive Performance Based on the Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Clinical Trials.
    Mátyus RO; Szikora Z; Bodó D; Vargáné Szabó B; Csupor É; Csupor D; Tóth B · Journal of clinical medicine · 2025
    Meta-analysis148 participants5 studies pooledMental Focus forTheanine
  4. Time for tea: mood, blood pressure and cognitive performance effects of caffeine and theanine administered alone and together.
    Rogers PJ; Smith JE; Heatherley SV; Pleydell-Pearce CW · Psychopharmacology · 2008
    Randomized trial48 participantsMental Focus Productivity Boost forTheanine
  5. Dose-Response Effects of Short-Term Rhodiola rosea (Golden Root Extract) Supplementation on Anaerobic Exercise Performance and Cognitive Function in Resistance-Trained Athletes: A Randomized, Crossover, Double-Blind, and Placebo-Controlled Study.
    Koozehchian MS; Newton AT; Mabrey G; Bonness FM; Rafajlovska R; Naderi A · Nutrients · 2025
    Randomized trial27 participantsBrain Health Fitness Mental Focus forRhodiola
  6. A combination of green tea, rhodiola, magnesium and B vitamins modulates brain activity and protects against the effects of induced social stress in healthy volunteers.
    Boyle NB; Billington J; Lawton C; Quadt F; Dye L · Nutritional neuroscience · 2022
    Randomized trial100 participantsBrain Health forRhodiola
  7. Rosenroot (Rhodiola rosea): traditional use, chemical composition, pharmacology and clinical efficacy.
    Panossian A; Wikman G; Sarris J · Phytomedicine : international journal of phytotherapy and phytopharmacology · 2010
    Narrative reviewBrain Health forRhodiola
  8. Rhodiola rosea in stress induced fatigue--a double blind cross-over study of a standardized extract SHR-5 with a repeated low-dose regimen on the mental performance of healthy physicians during night duty.
    Darbinyan V; Kteyan A; Panossian A; Gabrielian E; Wikman G; Wagner H · Phytomedicine : international journal of phytotherapy and phytopharmacology · 2001
    Randomized trial56 participantsBrain Health Productivity Boost forRhodiola
  9. Effects of a Rhodiola rosea extract on mental resource allocation and attention: An event-related potential dual task study.
    Koop T; Dienel A; Heldmann M; Münte TF · Phytotherapy research : PTR · 2021
    Single-arm trial50 participantsBrain Health Cognitive Support forRhodiola
  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 participantsBrain Health Cognitive Support forTheanine
  11. 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 trialBrain Health Stress Relief forTheanine
  12. 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.
    Payne ER; Aceves-Martins M; Dubost J; Greyling A; de Roos B · Nutrition reviews · 2025
    Meta-analysis50 studies pooledBrain Health Cognitive Support Mental Focus forTheanine
  13. Assessing the effects of caffeine and theanine on the maintenance of vigilance during a sustained attention task.
    Foxe JJ; Morie KP; Laud PJ; Rowson MJ; de Bruin EA; Kelly SP · Neuropharmacology · 2012
    Randomized trial27 participantsBrain Health Cognitive Support forTheanine
  14. Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study.
    Baba Y; Inagaki S; Nakagawa S; Kaneko T; Kobayashi M; Takihara T · Journal of medicinal food · 2021
    Randomized trialBrain Health Mental Focus Productivity Boost forTheanine
  15. Evidence-based efficacy of adaptogens in fatigue, and molecular mechanisms related to their stress-protective activity.
    Panossian A; Wikman G · Current clinical pharmacology · 2009
    Narrative reviewCognitive Support Mental Focus forRhodiola
  16. Central additive effect of Ginkgo biloba and Rhodiola rosea on psychomotor vigilance task and short-term working memory accuracy.
    Al-Kuraishy HM · Journal of intercultural ethnopharmacology · 2016
    Clinical trial112 participantsCognitive Support forRhodiola
  17. Clinical evidence for the adaptogenic effects of Withania somnifera and Rhodiola rosea - A systematic review with molecular interpretation of psychometric outcomes.
    Łuszczak J; Kocki J · Annals of agricultural and environmental medicine : AAEM · 2026
    Systematic review19 studies pooledCognitive Support Stress Relief forRhodiola
  18. A randomised, double-blind, placebo-controlled, parallel-group study of the standardised extract shr-5 of the roots of Rhodiola rosea in the treatment of subjects with stress-related fatigue.
    Olsson EM; von Schéele B; Panossian AG · Planta medica · 2009
    Randomized trial60 participantsCognitive Support Productivity Boost forRhodiola
  19. Dose-response effect of L-theanine on psychomotor speed, sustained attention, and inhibitory control: a double-blind, placebo-controlled, crossover study.
    Dassanayake TL; Wijesundara D; Kahathuduwa CN; Weerasinghe VS · Nutritional neuroscience · 2023
    Randomized trial32 participantsCognitive Support forTheanine
  20. Acute effects of theanine, caffeine and theanine-caffeine combination on attention.
    Kahathuduwa CN; Dassanayake TL; Amarakoon AMT; Weerasinghe VS · Nutritional neuroscience · 2018
    Clinical trial20 participantsCognitive Support Mental Focus forTheanine
  21. Cognitive and mood improvements of caffeine in habitual consumers and habitual non-consumers of caffeine.
    Haskell CF; Kennedy DO; Wesnes KA; Scholey AB · Psychopharmacology · 2005
    Randomized trial48 participantsEnergy forCaffeine
  22. Caffeine-containing energy drink improves physical performance of elite rugby players during a simulated match.
    Del Coso J; Ramírez JA; Muñoz G; Portillo J; Gonzalez-Millán C; Muñoz V; Barbero-Álvarez JC; Muñoz-Guerra J · Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme · 2016
    Randomized trial26 participantsEnergy forCaffeine
  23. Does Single or Combined Caffeine and Taurine Supplementation Improve Athletic and Cognitive Performance without Affecting Fatigue Level in Elite Boxers? A Double-Blind, Placebo-Controlled Study.
    Ozan M; Buzdagli Y; Eyipinar CD; Baygutalp NK; Yüce N; Oget F; Kan E; Baygutalp F · Nutrients · 2022
    Randomized trial20 participantsEnergy forCaffeine
  24. Trait Energy and Fatigue Modify the Effects of Caffeine on Mood, Cognitive and Fine-Motor Task Performance: A Post-Hoc Study.
    Fuller DT; Smith ML; Boolani A · Nutrients · 2021
    Randomized trialEnergy forCaffeine
  25. The Effect of Short-Term Rhodiola rosea Supplementation on Simulated Game Time, Perceived Fatigue, and Performance in Basketball Players.
    Wang J; Zhao H; Yu L; Zhao K; Jiang W; Liu S; Dai J; Xu L; Sun P; Yun H; Liu C · Nutrients · 2025
    Randomized trial48 participantsEnergy Fitness forRhodiola
  26. Effects of Rhodiola rosea on Physical and Decision-Making Performance in Football Players: A Randomised Controlled Trial.
    Dou Y; Wang Y; Zhang W; Jiang Y; Zhang J; Yang T; Han Z; Li Y; Liu C; Ren D · Nutrients · 2026
    Randomized trial24 participantsEnergy Fitness Mental Focus forRhodiola
  27. Combined Effects of Rhodiola Rosea and Caffeine Supplementation on Straight Punch Explosive Power in Untrained and Trained Boxing Volunteers: A Synergistic Approach.
    Tao B; Sun H; Li H; Xu Z; Xu Y; Chen L; Ma C; Zhang X; Yu L; Bao S; Liu C · Metabolites · 2025
    Randomized trial96 participantsEnergy forRhodiola
  28. Rhodiola rosea in Subjects with Prolonged or Chronic Fatigue Symptoms: Results of an Open-Label Clinical Trial.
    Lekomtseva Y; Zhukova I; Wacker A · Complementary medicine research · 2019
    Single-arm trial100 participantsEnergy Stress Relief forRhodiola
  29. Combined Rhodiola rosea and eccentric training boost endurance performance and lower-limb reactive strength in recreationally active women.
    Wang IL; Su Y; Zhang L; Tang M; Chen YM · Frontiers in physiology · 2025
    Randomized trial30 participantsEnergy Fitness forRhodiola
  30. Effect of caffeine ingestion on cycling performance: a systematic review and meta-analysis.
    Wu J; Xu K; Yin M; Ding X; Wang T; Zhang Q; Wu X; Xiao N · Frontiers in nutrition · 2026
    Meta-analysis226 participants20 studies pooledFitness forCaffeine
  31. Effects of Caffeine Intake on Endurance Running Performance and Time to Exhaustion: A Systematic Review and Meta-Analysis.
    Wang Z; Qiu B; Gao J; Del Coso J · Nutrients · 2023
    Meta-analysis254 participants21 studies pooledFitness forCaffeine
  32. Acute Effects of Caffeine Supplementation on Movement Velocity in Resistance Exercise: A Systematic Review and Meta-analysis.
    Raya-González J; Rendo-Urteaga T; Domínguez R; Castillo D; Rodríguez-Fernández A; Grgic J · Sports medicine (Auckland, N.Z.) · 2021
    Meta-analysis12 studies pooledFitness forCaffeine
  33. Sex Differences in the Ergogenic Response of Acute Caffeine Intake on Muscular Strength, Power and Endurance Performance in Resistance-Trained Individuals: A Randomized Controlled Trial.
    Montalvo-Alonso JJ; Ferragut C; Del Val-Manzano M; Valadés D; Roberts J; Pérez-López A · Nutrients · 2024
    Randomized trial76 participantsFitness forCaffeine
  34. Can I Have My Coffee and Drink It? A Systematic Review and Meta-analysis to Determine Whether Habitual Caffeine Consumption Affects the Ergogenic Effect of Caffeine.
    Carvalho A; Marticorena FM; Grecco BH; Barreto G; Saunders B · Sports medicine (Auckland, N.Z.) · 2022
    Meta-analysis60 studies pooledFitness forCaffeine
  35. The Impact of Rhodiola Rosea Extract on Strength Performance in Alternative Bench-Press and Bench-Pull Exercises Under Resting and Mental Fatigue Conditions: A Randomized, Triple-Blinded, Placebo-Controlled, Crossover Trial.
    Marcos-Frutos D; Leban Ž; Li Z; Zhang X; Lara PM; Alix-Fages C; Jiménez-Martínez P; Zebboudji N; Caillet A; Redondo B; Vera J; Janicijevic D; García-Ramos A · Nutrients · 2025
    Randomized trial18 participantsFitness forRhodiola
  36. Effects of modafinil and caffeine on night-time vigilance of air force crewmembers: A randomized controlled trial.
    Wingelaar-Jagt YQ; Bottenheft C; Riedel WJ; Ramaekers JG · Journal of psychopharmacology (Oxford, England) · 2023
    Randomized trial32 participantsMental Focus forCaffeine
  37. Acute effects of caffeine on attention: a comparison of non-consumers and withdrawn consumers.
    Smith AP; Christopher G; Sutherland D · Journal of psychopharmacology (Oxford, England) · 2013
    Randomized trial70 participantsMental Focus forCaffeine
  38. Performance and alertness effects of caffeine, dextroamphetamine, and modafinil during sleep deprivation.
    Wesensten NJ; Killgore WD; Balkin TJ · Journal of sleep research · 2006
    Randomized trial48 participantsMental Focus forCaffeine
  39. Effects of caffeine on mood and performance: a study of realistic consumption.
    Brice CF; Smith AP · Psychopharmacology · 2003
    Clinical trial24 participantsMental Focus forCaffeine
  40. Effects of caffeine or diphenhydramine on visual vigilance.
    Fine BJ; Kobrick JL; Lieberman HR; Marlowe B; Riley RH; Tharion WJ · Psychopharmacology · 1995
    Randomized trial24 participantsMental Focus forCaffeine
  41. The effectiveness and efficacy of Rhodiola rosea L.: a systematic review of randomized clinical trials.
    Hung SK; Perry R; Ernst E · Phytomedicine : international journal of phytotherapy and phytopharmacology · 2012
    Systematic review11 studies pooledMental Focus forRhodiola
  42. Effects of Rhodiola rosea supplementation on mental performance, physical capacity, and oxidative stress biomarkers in healthy men.
    Jówko E; Sadowski J; Długołęcka B; Gierczuk D; Opaszowski B; Cieśliński I · Journal of sport and health science · 2022
    Randomized trial26 participantsMental Focus Productivity Boost forRhodiola
  43. 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 participantsMental Focus Productivity Boost Stress Relief forTheanine
  44. 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.
    Karunaratne UW; Dassanayake TL · Nutritional neuroscience · 2025
    Randomized trial24 participantsMental Focus forTheanine
  45. A Randomized Study to Examine the Ability of a Caffeine-Based Energy Drink to Impact Energy Expenditure, Fat Oxidation, and Cognitive Performance.
    Krieger J; Schrautemeier A; Hagele A; Gaige C; Mennemeyer O; Tolbert S; Iannotti J; Kerksick C; Noonan C; Mumford P · Nutrients · 2025
    Randomized trial60 participantsMetabolism Boost forCaffeine
  46. Oolong tea increases metabolic rate and fat oxidation in men.
    Rumpler W; Seale J; Clevidence B; Judd J; Wiley E; Yamamoto S; Komatsu T; Sawaki T; Ishikura Y; Hosoda K · The Journal of nutrition · 2001
    Randomized trial12 participantsMetabolism Boost forCaffeine
  47. Effect of caffeine intake on fat oxidation rate during exercise: is there a dose-response effect?
    Gutiérrez-Hellín J; Aguilar-Navarro M; Ruiz-Moreno C; Muñoz A; Varillas-Delgado D; Amaro-Gahete FJ; Del Coso J · European journal of nutrition · 2023
    Randomized trial18 participantsMetabolism Boost forCaffeine
  48. Comparison of changes in energy expenditure and body temperatures after caffeine consumption.
    Koot P; Deurenberg P · Annals of nutrition & metabolism · 1995
    Randomized trial12 participantsMetabolism Boost forCaffeine
  49. Caffeine Increases Work Done above Critical Power, but Not Anaerobic Work.
    Silveira R; Andrade-Souza VA; Arcoverde L; Tomazini F; Sansonio A; Bishop DJ; Bertuzzi R; Lima-Silva AE · Medicine and science in sports and exercise · 2018
    Randomized trial9 participantsMetabolism Boost forCaffeine
  50. Efficacy of Pharmacological Interventions in Milder Depression: A Systematic Review and Meta-Analysis.
    Urata M; Sakurai H; Ueno F; Maruki T; Tada T; Uchida T; Matsumoto Y; Murao M; Tomita M; Baba H; Kato M; Tsuboi T; Watanabe K · Neuropsychopharmacology reports · 2025
    Meta-analysis1,049 participants2 studies pooledMood Support forRhodiola
  51. The Effect of Acute Rhodiola rosea Ingestion on Exercise Heart Rate, Substrate Utilisation, Mood State, and Perceptions of Exertion, Arousal, and Pleasure/Displeasure in Active Men.
    Duncan MJ; Clarke ND · Journal of sports medicine (Hindawi Publishing Corporation) · 2015
    Clinical trial10 participantsMood Support forRhodiola
  52. Herbal medicine for depression, anxiety and insomnia: a review of psychopharmacology and clinical evidence.
    Sarris J; Panossian A; Schweitzer I; Stough C; Scholey A · European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology · 2012
    Systematic review66 studies pooledMood Support forRhodiola
  53. Medicinal Plants in the Treatment of Depression. II: Evidence from Clinical Trials.
    Moragrega I; Ríos JL · Planta medica · 2022
    Systematic reviewMood Support forRhodiola
  54. Multicenter, open-label, exploratory clinical trial with Rhodiola rosea extract in patients suffering from burnout symptoms.
    Kasper S; Dienel A · Neuropsychiatric disease and treatment · 2020
    Single-arm trial118 participantsMood Support forRhodiola
  55. l-theanine adjunct to sertraline for major depressive disorder: A randomized, double-blind, placebo-controlled clinical trial.
    Shamabadi A; Kafi F; Arab Bafrani M; Asadigandomani H; A Basti F; Akhondzadeh S · Journal of affective disorders · 2023
    Randomized trial60 participantsMood Support forTheanine
  56. 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 participantsMood Support Stress Relief forTheanine
  57. The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systematic Review.
    Williams JL; Everett JM; D'Cunha NM; Sergi D; Georgousopoulou EN; Keegan RJ; McKune AJ; Mellor DD; Anstice N; Naumovski N · Plant foods for human nutrition (Dordrecht, Netherlands) · 2020
    Systematic review9 studies pooledMood Support forTheanine
  58. 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 participantsMood Support Stress Relief forTheanine
  59. Anti-stress effect of theanine on students during pharmacy practice: positive correlation among salivary α-amylase activity, trait anxiety and subjective stress.
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