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L-Theanine 100 mg

Life Extension
4.7
★ ★ ★ ★ ★
(145 ratings)
Theanine 100 mg
Product Image
Score93

A gentle 100 mg dose of L-theanine to help support a calm mind and focused alertness throughout the day.

How scoring works
Quantity:60 Capsule(s) • (60 servings)
Goals:
Brain Health
Sleep Support
Stress Relief
Mood Support
Mental Focus
Cognitive Support
Productivity Boost

Score 93

A gentle 100 mg dose of L-theanine to help support a calm mind and focused alertness throughout the day.

How scoring works
$18.00($0.30 per serving)
Walmart
$ 12.75
Pure Formulas
$ 18.00
Vitacost
$ 18.00
Vitacost
$ 18.00
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Analysis

L-theanine is an amino acid found in green tea that helps support relaxation by modulating brain waves. This 100 mg dose is a gentle starting point for anyone looking to stay calm and productive during a busy workday.

It works well for supporting sleep by quieting mental chatter before bed, or for mental focus by reducing jitters. The single-ingredient approach from Life Extension ensures a high standard of purity.

Pros

  • Supports relaxation without sleepiness
  • Great for focus and stress relief
  • Clean, single-ingredient formula
  • Well-trusted brand

Cons

  • Dose may be too low for some
  • Relatively simple for the price

Warnings

  • Monitor how you feel before driving
  • Safe for most adults

Nutrient quality

91 Highest impact

Utilization of the pure L-isomer supports efficient crossing of the blood-brain barrier for neurotransmitter modulation. Dosing matches established clinical thresholds for daily maintenance of focus.

Ingredient transparency

98 Highest impact

Active amounts are explicitly disclosed, ensuring users can accurately track their daily amino acid intake. Serving instructions are concise and well-defined for daily use.

Customer satisfaction

93 Highest impact

Consumer ratings reflect a high degree of trust and consistent performance for cognitive and stress goals. Broad usage suggests the capsule format is well-tolerated by most individuals.

Value for money

91 Highest impact

Cost per serving is competitive for a reputable brand known for stringent quality control measures. Quality of the raw materials justifies the investment for long-term support.

Report analysis

Goals

Brain Health
Impact
Highest effect
A+ Goal FitA Strength of SupportB- CoverageA+ Formula Quality

L-Theanine is provided at a 100mg dose to support mental focus and a calm mental state. This amino acid may contribute to the induction of alpha brain waves, facilitating attention without jittery side effects.

A standard 100mg dose provides a foundational level of support for mental resilience under stress. This single-ingredient approach appears well aligned with research supporting its role in non-sedative relaxation.

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Sleep Support
Impact
Highest effect
A Goal FitA+ Strength of SupportC- CoverageA+ Formula Quality

L-theanine provides focused support for inducing a state of mental relaxation without excessive sedation. This single-active formula appears well aligned with reducing the stress that can interfere with sleep quality.

L-theanine may contribute to improved sleep latency and a calm nervous system. A 100mg dose supports the transition into a restful nighttime state.

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Stress Relief
Impact
Highest effect
A Goal FitA Strength of SupportC- CoverageA Formula Quality

L-theanine at 100mg supports the body's natural production of inhibitory neurotransmitters and may contribute to a state of relaxed alertness. This amino acid appears well-aligned for those seeking to modulation their nervous system response to acute stress without causing significant drowsiness.

Providing 100mg is a meaningfully potent dose that fits squarely within effective clinical ranges for inducing relaxation. This single-ingredient formula offers deep support for the alpha-wave pathway but lacks the broad adaptogenic or mineral support found in complex products.

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Mood Support
Impact
Highest effect
A Goal FitB+ Strength of SupportC+ CoverageA+ Formula Quality

L-theanine is provided at a dose of 100 mg per serving to support a calm and balanced mental state. This amino acid is recognized for its ability to promote relaxation without causing drowsiness.

While the dose is on the lower end of the clinical range, it provides steady support for emotional resilience. The simple, single-ingredient formula avoids unnecessary complexity and maintains high alignment with relaxation goals.

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Mental Focus
Impact
Highest effect
A+ Goal FitB Strength of SupportC- CoverageA+ Formula Quality

L-Theanine supports a state of calm focus by Promoting alpha brain wave activity and modulating neurotransmitters involved in attention. This 100mg dose provides a foundational level of support for mental clarity and stress management.

Improved concentration and reduced mental tension may contribute to more productive focus during demanding tasks. It is a clean and straightforward supplement for those seeking a single-ingredient nootropic.

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Cognitive Support
Impact
Highest effect
A Goal FitB+ Strength of SupportC CoverageA- Formula Quality

Calm focus and relaxation are supported using a foundational amino acid.

L-Theanine provides a 100mg dose per capsule to support alpha brain wave activity without sedation.

View goal →
Productivity Boost
Impact
Highest effect
B+ Goal FitA- Strength of SupportD+ CoverageA+ Formula Quality

This single-active supplement provides L-theanine to support a state of calm focus and mental clarity. It appears well aligned for users seeking to manage stress without compromising alertness or cognitive performance.

The 100mg dose is an effective baseline for inducing alpha-wave brain activity associated with relaxed wakefulness. The clean capsule format ensures efficient delivery of the active isomer.

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Ingredients

IngredientAmount per serving
L-Theanine
100 mg
Adults 18–50
Report overview
Theanine · 100 mg OverallScore88
B+ Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyB+ Value
This straightforward L-Theanine supplement provides a clean 100mg dose in a single capsule. It is an ideal entry-level product for those looking to test the focus-enhancing effects of theanine without other active ingredients.
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Double Strength L-Theanine 200 mg

NOW
4.7
★★★★★
(42894 ratings)
The significant 200mg dose and addition of inositol provide much better cognitive support for a very similar overall cost. It represents a high-performing and value-driven choice for daily focus.
Other sellers (5)
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L-Theanine 200 mg Double Strength

Swanson
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★★★★★
(1058 ratings)
Features 200mg of Suntheanine, providing more of the high-quality active ingredient per serving for excellent long-term value. It balances premium sourcing with a very sustainable price structure.
Other sellers (2)
95 Value

L-Theanine 150 mg

Doctor's Best
4.6
★★★★★
(8423 ratings)
Offers a higher 150mg dose in a bulk 90-count bottle, providing consistent results and high transparency for a better cost. It is an ideal choice for users who want clinical-strength focus daily.
Other sellers (4)
97 Performance

L-Theanine 100 mg

California Gold Nutrition
4.7
★★★★★
(24551 ratings)
Uses the premium AlphaWave branded ingredient, ensuring higher purity and standardized performance compared to generic theanine. This specific source is superior for inducing a state of relaxed wakefulness.
Other sellers (1)
95 Performance

Suntheanine L-Theanine 125 mg

Natural Factors Stress-Relax
4.7
★★★★★
(1505 ratings)
Increases the active dose to 250mg of branded Suntheanine, offering a therapeutic level of support for relaxation. The focus on high-purity materials provides a more reliable and potent state of calm.
Other sellers (2)
95 Performance

ZenMind

NutriCology
4.6
★★★★★
(230 ratings)
Pairs high-purity GABA with theanine for a multi-faceted approach to nervous system relaxation. This synergistic formula is more effective at quieting a busy mind than theanine alone.
Other sellers (3)
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