Theanine
Theanine is a unique amino acid that is a derivative of glutamic acid and is most prominently found in green and black tea leaves. Unlike other amino acids, L-Theanine is not commonly incorporated into proteins. Its primary mechanism involves crossing the blood-brain barrier to influence brain activity, particularly by increasing alpha brain wave activity, which is associated with a state of 'wakeful relaxation'. By modulating neurotransmitters such as GABA, dopamine, and serotonin, Theanine helps to reduce feelings of stress and anxiety while improving focus and concentration. This leads to a state of calm alertness, making it a popular supplement for those seeking to enhance cognitive performance and manage daily stressors without the sedative effects often associated with other relaxation aids. Often consumed in tea or as a dietary supplement, Theanine is also valued for its potential to improve sleep quality by promoting relaxation before bedtime. It is generally well-tolerated with a low incidence of side effects, making it a safe choice for many individuals looking to support mental well-being and cognitive function.
Green tea (Camellia sinensis)Black tea (Camellia sinensis)Some mushrooms (e.g., Bay Bolete)
Cheapest Theanine supplements
Discover the most affordable Theanine supplements designed to support mood, enhance cognitive function, improve sleep, boost energy, and relieve stress for overall brain health and productivity.
Best Theanine supplements
Discover the best Theanine supplements for mood support, cognitive function, stress relief, and improved sleep.
Value Theanine Supplements
Discover the best value Theanine supplements chosen to support mood, cognitive function, sleep, energy, stress relief, mental focus, brain health, weight loss, and productivity boost.
Minimum100 mg
Maximum400 mg
Impact
High effect
Typical dose:100–200 mg
Found in green tea, L-Theanine is an amino acid that modulates neurotransmitters like GABA and dopamine. It is highly effective at taking the 'edge' off stimulants like caffeine, resulting in smooth, focused energy and reduced anxiety.
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Impact
High effect
Typical dose:100–200 mg
Found primarily in green tea, L-Theanine modulates neurotransmitters like dopamine and GABA. It provides a non-drowsy relaxation effect that can mitigate the jitteriness of caffeine, leading to a synergistic improvement in smooth, sustained mental focus.
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Impact
High effect
Typical dose:100–400 mg
L-Theanine is an amino acid that can cross the blood-brain barrier and increase alpha brain wave activity, which is associated with a state of 'relaxed wakefulness'. It can modulate neurotransmitters like GABA and dopamine, improving focus and attention without sedation.
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Impact
High effect
Typical dose:100–400 mg
L-Theanine, an amino acid found in green tea, is known for its ability to induce a state of 'calm alertness' by increasing alpha brain wave activity. It helps quiet a racing mind and reduces stress, addressing common barriers to falling asleep. It does not act as a sedative but rather facilitates the transition into sleep.
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Impact
High effect
Typical dose:100–200 mg
This amino acid, commonly found in green tea, can cross the blood-brain barrier and influence neurotransmitter levels. It enhances GABA, serotonin, and dopamine, leading to a quick-acting reduction in mental and physical stress while improving focus.
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add_circle_outline Positive Interactions
Caffeine
Enhances cognitive benefits (focus, attention) and mitigates potential side effects of caffeine like jitters and anxiety, promoting 'calm alertness'.
Magnesium
May synergistically support relaxation and neurological function.
GABA
Theanine can influence GABA levels in the brain, potentially enhancing its calming and anxiolytic effects.
Ashwagandha
Both are adaptogens known for stress reduction; combining them may have synergistic effects on promoting relaxation and mental well-being.
Melatonin
By promoting relaxation, Theanine may indirectly support the sleep-inducing effects of melatonin.
remove_circle_outline Negative Interactions
Hawthorn
May lead to an additive mild hypotensive effect, particularly in individuals prone to low blood pressure, as both can mildly lower blood pressure.
Valerian
May increase sedative effects and potentially an additive mild blood pressure-lowering effect if taken together, especially in sensitive individuals.
78 Budget 
L-Theanine 200 mg
Nature's Way
4.6
★★★★★
(1057 ratings)
Theanine: 200 mg
A reputable L-Theanine product at a standard dose with high customer satisfaction, offering good value, though not the most economical option.
65 Best 
L-Theanine 250 mg
Kirkman
4.6
★★★★★
(8 ratings)
Theanine: 250 mg
A high-dose L-Theanine capsule from Kirkman, offering 250mg per serving and a large supply, but with very limited customer feedback.
88 Best 
L-Theanine
NOW
4.7
★★★★★
(697 ratings)
Theanine: 285 mg
A high-dose liquid L-Theanine option from NOW, offering good value and versatility for various calming and focus-related goals.
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Day Starter
Source Naturals
4.9
★★★★★
(7 ratings)
Theanine: 200 mg
This product combines caffeine from green tea with L-Theanine to offer a noticeable energy lift and improved focus, aiming for smooth alertness without excessive nervousness.
85 Budget 
Anxiety & Stress Relief
Nature's Bounty
4.5
★★★★★
(9988 ratings)
Theanine: 200 mg
This supplement offers a focused blend of Ashwagandha and L-Theanine, providing support for stress relief and a more relaxed state for daily well-being at an appealing price.
58 Budget 
L-Theanine 200 mg
Bluebonnet
4.0
★★★★★
(4 ratings)
Theanine: 200 mg
A basic L-Theanine product at a standard dose, but hindered by very limited customer reviews and a small quantity of servings.
82 Budget 
Theanine Serene with Relora
Source Naturals Serene Science
4.6
★★★★★
(4667 ratings)
Theanine: 200 mg
This product combines L-Theanine, GABA, Taurine, and Magnesium with Holy Basil and a moderate dose of Relora to support relaxation and a balanced response to daily stress.
55 Best 
Alpha GABA
NS
3.7
★★★★★
(3 ratings)
Theanine: 400 mg
This product features a blend of L-Theanine, Ashwagandha, and B6, which may contribute to relaxation and mood support, but the inclusion of an undisclosed proprietary blend impacts its clarity and value.
85 Best 
Pulse Fruit Punch
Legion
4.8
★★★★★
(37 ratings)
Theanine: 350 mg
Pulse Fruit Punch is a high-stimulant pre-workout supplement packed with ingredients to support energy, focus, and athletic performance during intense workouts, plus added electrolytes.
72 Best 
Neuro-T
LifeSeasons
4.5
★★★★★
(209 ratings)
Theanine: 250 mg
This formula blends stimulating ingredients with calming herbs and cognitive enhancers, aiming to support focused energy and mental clarity.
77 Best 
Focus-R
LifeSeasons
4.5
★★★★★
(535 ratings)
Theanine: 250 mg
This complex formula blends energizing compounds with calming herbs and cognitive enhancers to support focused attention and mental performance.
85 Value 
L-Theanine 200 mg
Advance Physician Formulas
4.7
★★★★★
(619 ratings)
Theanine: 200 mg
An excellent value L-Theanine product at a standard dose, featuring a very low price per serving and strong customer satisfaction.
78 Budget 
Triple Action Sleep
Solgar
4.5
★★★★★
(50 ratings)
Theanine: 200 mg
This tablet provides a robust blend of 10mg melatonin, 200mg L-theanine, and a 50mg herbal blend, making it a strong option for comprehensive sleep and relaxation support.
70 Best 
L-Theanine 200 mg
Health Thru Nutrition
5.0
★★★★★
(1 ratings)
Theanine: 200 mg
A budget-friendly L-Theanine supplement from Health Thru Nutrition, offering 200mg of green tea-derived PhytoSure L-Theanine in a vegecap, but with almost no customer feedback.
90 Value 
Double Strength L-Theanine 200 mg
NOW
4.7
★★★★★
(41433 ratings)
Theanine: 200 mg
A NOW supplement featuring 200mg L-Theanine and 100mg Inositol per capsule, designed for enhanced mood and nervous system support at a good value.
80 Budget 
Restful Sleep Blackberry Zen
OLLY
4.4
★★★★★
(4924 ratings)
Theanine: 200 mg
An OLLY gummy product blending 200mg L-Theanine with 3mg Melatonin and various herbal extracts, specifically formulated for comprehensive restful sleep support.
85 Value 
Triple Action Sleep
Solgar
4.3
★★★★★
(1955 ratings)
Theanine: 200 mg
This tablet offers a powerful combination of 10mg melatonin, 200mg L-theanine, and a 50mg herbal blend in a value-sized pack, aiming for comprehensive sleep and relaxation.
85 Value 
L-Theanine 150 mg
Doctor's Best
4.6
★★★★★
(8126 ratings)
Theanine: 150 mg
A Doctor's Best L-Theanine supplement, offering 150mg per veggie cap at an excellent price, backed by extensive positive customer feedback.
50 Best 
Alpha GABA PM
NS
3.8
★★★★★
(19 ratings)
Theanine: 400 mg
A high-dose L-Theanine and Melatonin product for sleep, but its very high price and proprietary blend significantly reduce its appeal and transparency.
88 Value 
Sleep Regimen 3-in-1
NOW
4.5
★★★★★
(1136 ratings)
Theanine: 200 mg
This product combines L-Theanine, 5-HTP, and Melatonin in a single capsule, aiming to support relaxation and healthy sleep patterns effectively.
88 Value 
Double Strength L-Theanine 200 mg
NOW
4.7
★★★★★
(41457 ratings)
Theanine: 200 mg
A highly affordable L-Theanine supplement at 200mg, with added Inositol for mood support, making it a strong value pick from a popular brand.
87 Value 
L-Theanine 200 mg
California Gold Nutrition
4.7
★★★★★
(15182 ratings)
Theanine: 200 mg
An incredibly affordable L-Theanine supplement at an effective 200mg dose, offering excellent value and broad customer approval for basic calm and focus.
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Gorilla Dream
Gorilla Mind
5.0
★★★★★
(1 ratings)
Theanine: 250 mg
Gorilla Dream offers a comprehensive blend of ingredients designed to support relaxation, mood, and cognitive function, combining calming compounds with those that may influence alertness and focus.
Average$31.36
Median$27.58
Average$0.80
Median$0.58
Average$0.37
Median$0.29
Reference amount: 100 mg