L-Theanine لـ Attention & Focus Difficulties
B الأدلة تدعم ذلك تجربة عشوائية واحدة على الأقل، مع نتائج متسقة في معظمها.The L-theanine + caffeine combination is one of the most replicated nootropic pairings in cognitive research, consistently showing improvements in attention, task switching, and alertness without jitteriness.
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B
الخلاصة
The L-theanine + caffeine combination is one of the most replicated nootropic pairings in cognitive research, consistently showing improvements in attention, task switching, and alertness without jitteriness.
Key Study Findings
Systematic Review
Efficiency of Different Supplements in Alleviating Symptoms of ADHD with or Without the Use of …
Dose: None
مقابل: Placebo or methylphenidate
Outcome: ADHD symptom severity (inattention, hyperactivity)
التأثير: None
None
المجتمع المدروس: ADHD patients (systematic review of supplements)
Systematic Review
The effects of L-theanine supplementation on the outcomes of patients with mental disorders: a systematic …
Dose: None
مقابل: None
Outcome: Anxiety symptoms
التأثير: None
None
المجتمع المدروس: Schizophrenia patients
Systematic Review
Association between sleep pattern and pharmacological treatment in children with attention deficit disorder with hyperactivity: …
Dose: None
مقابل: None
Outcome: sleep quality
التأثير: None
None
المجتمع المدروس: Children
Randomized Controlled Trial
4.3 weeks
Single-blind
Assessing brain function in stressed healthy individuals following the use of a combination of green …
Dose: None
مقابل: placebo
Outcome: Brain response to stress and quality of life
التأثير: None
p = 0.001
المجتمع المدروس: Chronically stressed but healthy subjects
Systematic Review
884 weeks
The Cognitive-Enhancing Outcomes of Caffeine and L-theanine: A Systematic Review.
Dose: 9.4%
مقابل: None
Outcome: None
التأثير: None
None
المجتمع المدروس: None
Randomized Controlled Trial
Effects of L-theanine-caffeine combination on sustained attention and inhibitory control among children with ADHD: a …
Dose: 2.5 mg/kg
مقابل: Placebo
Outcome: None
التأثير: None
p = 0.040
المجتمع المدروس: Children with ADHD
Key Statistics
20
الدراسات
1500
المشاركون
↑
Positive
B
التقييم
Referenced Papers
Efficiency of Different Supplements in Alleviating Symptoms of ADHD with or Without the Use of Stimulants: A Systematic Review.
Systematic Review
Nutrients
2025
1 اقتباسات
The effects of L-theanine supplementation on the outcomes of patients with mental disorders: a systematic review.
Systematic Review
BMC psychiatry
2024
12 اقتباسات
Association between sleep pattern and pharmacological treatment in children with attention deficit disorder with hyperactivity: a systematic review.
Systematic Review
Revista paulista de …
2023
3 اقتباسات
Frontiers in nutrition
2023
3 اقتباسات
Cureus
2021
20 اقتباسات
Scientific reports
2020
34 اقتباسات
Journal of psychiatric …
2019
46 اقتباسات
Acta neuropsychiatrica
2017
84 اقتباسات
Alternative medicine review …
2011
82 اقتباسات
Dosage & Usage
mg = milligrams · mcg = micrograms (1,000× smaller) · IU = International Units
الجرعات الشائعة
- general:
- 100-200 mg/day
- withcaffeine:
- 200 mg L-theanine + 100 mg caffeine
الحد الأعلى: 900 mg/day (no adverse effects observed in studies)
الجرعات المدروسة في الأبحاث
| الجرعة | المدة | التأثير | ن |
|---|---|---|---|
| None | -- | Mixed | -- |
| None | -- | Positive | -- |
| None | -- | Mixed | -- |
| None | 4.3 weeks | Positive | -- |
| 9.4% | 884 weeks | Positive | -- |
| 2.5 mg/kg | -- | Negative | -- |
| 450-900 mg L-theanine daily | 10 weeks | Neutral | 46 |
| 250 mg/day | 8 weeks | Positive | 20 |
أفضل وقت للتناول: Morning or as needed; rapid onset (30-60 minutes)
Safety & Side Effects
الآثار الجانبية المُبلّغ عنها
- ⚠ Generally very well-tolerated
- ⚠ Mild drowsiness in sensitive individuals
- ⚠ Mild headache (rare)
التفاعلات المعروفة
- ● Antihypertensive drugs (may enhance blood pressure lowering)
- ● Stimulant medications (counteracts some stimulant side effects)
- ● Sedative medications (additive calming effects)
الحد الأقصى المسموح به: 900 mg/day (no adverse effects observed in studies)
استشر مقدم الرعاية الصحية دائماً قبل البدء بأي مكمل غذائي.
Frequently Asked Questions
Does L-Theanine help with Attention & Focus Difficulties?
Based on 20 studies with 1,500 participants, there is moderate evidence from clinical studies that L-Theanine may support Attention & Focus Difficulties management. Our evidence grade is B (Good Evidence).
How much L-Theanine should I take for Attention & Focus Difficulties?
Studies have used various dosages. A commonly studied range is 100-200 mg/day. Always consult your healthcare provider before starting any supplement regimen.
Are there side effects of L-Theanine?
Reported side effects may include Generally very well-tolerated, Mild drowsiness in sensitive individuals, Mild headache (rare). Most side effects are mild and dose-dependent. Consult your doctor if you experience any adverse reactions.
How strong is the evidence for L-Theanine and Attention & Focus Difficulties?
We rate the evidence as Grade B (Good Evidence). This rating is based on 20 peer-reviewed studies with 1,500 total participants. The overall direction of effect is positive.
Related Evidence
مكونات أخرى لـ Attention & Focus Difficulties
L-Theanine لحالات أخرى
References
- [1] Shatha Al Shahab et al.. Nutrients. 2025. Efficiency of Different Supplements in Alleviating Symptoms of ADHD with or Without the Use of Stimulants: A Systematic Review. doi:10.3390/nu17091482 PubMed
- [2] Reza Moshfeghinia et al.. BMC Psychiatry. 2024. The effects of L-theanine supplementation on the outcomes of patients with mental disorders: a systematic review. doi:10.1186/s12888-024-06285-y PubMed
- [3] Nathalia Sena Rocha et al.. Rev Paul Pediatr. 2023. Association between sleep pattern and pharmacological treatment in children with attention deficit disorder with hyperactivity: a systematic review. doi:10.1590/1984-0462/2023/41/2022065 PubMed
- [4] Gisèle Pickering et al.. Front Nutr. 2023. Assessing brain function in stressed healthy individuals following the use of a combination of green tea, Rhodiola, magnesium, and B … doi:10.3389/fnut.2023.1211321 PubMed
- [5] Anas Anas Sohail et al.. Cureus. 2021. The Cognitive-Enhancing Outcomes of Caffeine and L-theanine: A Systematic Review. doi:10.7759/cureus.20828 PubMed
- [6] Chanaka N Kahathuduwa et al.. Sci Rep. 2020. Effects of L-theanine-caffeine combination on sustained attention and inhibitory control among children with ADHD: a proof-of-concept neuroimaging RCT. doi:10.1038/s41598-020-70037-7 PubMed
- [7] Jerome Sarris et al.. J Psychiatr Res. 2019. L-theanine in the adjunctive treatment of generalized anxiety disorder: A double-blind, randomised, placebo-controlled trial. doi:10.1016/j.jpsychires.2018.12.014 PubMed
- [8] Shinsuke Hidese et al.. Acta Neuropsychiatr. 2017. Effects of chronic l-theanine administration in patients with major depressive disorder: an open-label study. doi:10.1017/neu.2016.33 PubMed
- [9] Michael R Lyon et al.. Altern Med Rev. 2011. The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, … PubMed
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