L-Theanine

Quick Facts

Form: L-Theanine (from green tea extract)

Dosage: 100 mg

Evidence Strength: Strong - Well studied in relation to relaxation, attention, and mental performance.

Time to Effect: Typically observed within 30–60 minutes of consumption.

L-Theanine is an amino acid found naturally in green tea that supports calm focus and balanced alertness. At Spyr, we include it for its role in promoting a smooth, steady energy profile that complements other performance nutrients.

Benefits

Benefit Evidence Level Typical Dosage Notes
Supports a state of calm focus without sedation. Strong 100–200 mg per day L-Theanine promotes alpha brain wave activity, which is linked to relaxed but alert mental states. This makes it useful for maintaining concentration while keeping stress levels balanced.
Supports sustained attention and concentration during mentally demanding tasks. Strong 100–200 mg per day Studies show that L-Theanine can improve selective attention and reduce mind-wandering, particularly when combined with other nutrients. This makes it valuable for both work and training performance.
Contributes to smoother, more balanced energy levels across the day. Moderate 100–200 mg per day By modulating neurotransmitter activity, L-Theanine can help reduce overstimulation from other energising compounds. This creates a more steady and sustainable energy profile.
Plays a role in supporting the body’s natural response to stress. Moderate 100–200 mg per day L-Theanine influences neurotransmitters such as GABA and dopamine, which are involved in relaxation and mood. Evidence shows it can support stress management without drowsiness.
Promotes relaxation while maintaining alertness. Strong 100–200 mg per day Unlike sedatives, L-Theanine encourages a calm state without impairing alertness. This balance makes it effective for supporting recovery while still being appropriate for daytime use.
Evidence Level Strong
Notes L-Theanine promotes alpha brain wave activity, which is linked to relaxed but alert mental states. This makes it useful for maintaining concentration while keeping stress levels balanced.
Evidence Level Strong
Notes Studies show that L-Theanine can improve selective attention and reduce mind-wandering, particularly when combined with other nutrients. This makes it valuable for both work and training performance.
Evidence Level Moderate
Notes By modulating neurotransmitter activity, L-Theanine can help reduce overstimulation from other energising compounds. This creates a more steady and sustainable energy profile.
Evidence Level Moderate
Notes L-Theanine influences neurotransmitters such as GABA and dopamine, which are involved in relaxation and mood. Evidence shows it can support stress management without drowsiness.
Evidence Level Strong
Notes Unlike sedatives, L-Theanine encourages a calm state without impairing alertness. This balance makes it effective for supporting recovery while still being appropriate for daytime use.

Mechanism

L-Theanine influences neurotransmitter activity and increases alpha brain wave patterns, which are associated with calm but alert states. It helps balance stimulating inputs, supporting focus without overstimulation. In combination with other nutrients, it contributes to steady mental performance.

Forms & Timing

Spyr Rise provides 100 mg of L-Theanine, a dosage chosen to support calm focus without sedation. Taken in the morning, it helps balance energy levels and creates a smooth performance profile that carries through the day.

Safety

Consult a healthcare professional before use if you are pregnant, nursing, under 18, or have a medical condition.

Naturally present in tea and widely consumed as part of the diet. Recognised as safe at standard supplemental levels.

Studies

Study Title Outcome Year Design Population Dosage Duration Study Type Takeaway
Effects of L-Theanine on alpha brain wave activity L-Theanine supplementation increased alpha brain wave activity, associated with relaxed but alert mental states. 1999 Randomized, placebo-controlled trial Healthy adults 50–200 mg single doses Randomized controlled trial Demonstrates the neural basis for calm but focused states, directly supporting Spyr’s “calm focus” benefit.
L-Theanine, caffeine and attention: a study of sustained attention Combination of L-Theanine with caffeine improved accuracy and reduced mind-wandering in attention tasks compared to placebo. 2008 Randomized, double-blind, placebo-controlled Healthy adults performing sustained attention tasks 97 mg L-Theanine + 40 mg caffeine, acute dose Randomized controlled trial Supports L-Theanine’s role in selective attention and concentration, particularly in synergy with caffeine.
L-Theanine reduces stress-related symptoms and improves cognitive performance Daily L-Theanine reduced stress-related symptoms and supported cognitive performance compared with placebo. 2019 Randomized, placebo-controlled trial Adults with moderate stress 200 mg/day for 4 weeks Randomized controlled trial Evidence that L-Theanine helps maintain steady performance and balanced energy under stress.
The effects of L-Theanine on physiological responses to acute stress L-Theanine reduced heart rate and salivary cortisol responses to stress compared with placebo. 2007 Randomized, double-blind, placebo-controlled crossover Healthy adults 200 mg single dose Randomized crossover trial Confirms L-Theanine’s role in moderating stress responses without sedation.
Effects of L-Theanine on relaxation using EEG and self-report measures L-Theanine increased relaxation ratings and alpha brain wave activity without causing drowsiness. 2006 Randomized, placebo-controlled Healthy young adults 200 mg single dose Randomized controlled trial Supports Spyr’s positioning of L-Theanine as promoting relaxation while maintaining alertness, safe for daytime use.
Effects of L-Theanine on alpha brain wave activity
Outcome L-Theanine supplementation increased alpha brain wave activity, associated with relaxed but alert mental states.
Year 1999
Design Randomized, placebo-controlled trial
Population Healthy adults
Dosage Duration 50–200 mg single doses
Study Type Randomized controlled trial
Takeaway Demonstrates the neural basis for calm but focused states, directly supporting Spyr’s “calm focus” benefit.
L-Theanine, caffeine and attention: a study of sustained attention
Outcome Combination of L-Theanine with caffeine improved accuracy and reduced mind-wandering in attention tasks compared to placebo.
Year 2008
Design Randomized, double-blind, placebo-controlled
Population Healthy adults performing sustained attention tasks
Dosage Duration 97 mg L-Theanine + 40 mg caffeine, acute dose
Study Type Randomized controlled trial
Takeaway Supports L-Theanine’s role in selective attention and concentration, particularly in synergy with caffeine.
L-Theanine reduces stress-related symptoms and improves cognitive performance
Outcome Daily L-Theanine reduced stress-related symptoms and supported cognitive performance compared with placebo.
Year 2019
Design Randomized, placebo-controlled trial
Population Adults with moderate stress
Dosage Duration 200 mg/day for 4 weeks
Study Type Randomized controlled trial
Takeaway Evidence that L-Theanine helps maintain steady performance and balanced energy under stress.
The effects of L-Theanine on physiological responses to acute stress
Outcome L-Theanine reduced heart rate and salivary cortisol responses to stress compared with placebo.
Year 2007
Design Randomized, double-blind, placebo-controlled crossover
Population Healthy adults
Dosage Duration 200 mg single dose
Study Type Randomized crossover trial
Takeaway Confirms L-Theanine’s role in moderating stress responses without sedation.
Effects of L-Theanine on relaxation using EEG and self-report measures
Outcome L-Theanine increased relaxation ratings and alpha brain wave activity without causing drowsiness.
Year 2006
Design Randomized, placebo-controlled
Population Healthy young adults
Dosage Duration 200 mg single dose
Study Type Randomized controlled trial
Takeaway Supports Spyr’s positioning of L-Theanine as promoting relaxation while maintaining alertness, safe for daytime use.

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Frequently Asked Questions

Question Answer
Why is L-Theanine included in Spyr Rise? L-Theanine is found naturally in tea leaves and is valued for promoting calm alertness.
How does L-Theanine support calm focus? It is associated with increased alpha brainwave activity, linked to a calm yet alert state.
Can L-Theanine make you drowsy? L-Theanine promotes relaxation without sedation, meaning it does not cause drowsiness when taken alone.
Is L-Theanine safe for daily use? Yes, L-Theanine is considered safe for daily use and has been consumed for centuries in tea.
Answer L-Theanine is found naturally in tea leaves and is valued for promoting calm alertness.
Answer It is associated with increased alpha brainwave activity, linked to a calm yet alert state.
Answer L-Theanine promotes relaxation without sedation, meaning it does not cause drowsiness when taken alone.
Answer Yes, L-Theanine is considered safe for daily use and has been consumed for centuries in tea.

Still curious?

If you still have any questions about L-Theanine, head on over to our contact page and fire away - our team will be happy to assist.

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