What are the effects of theanine and caffeine together?
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Effects of Theanine and Caffeine Together
Introduction to Theanine and Caffeine Combination
Theanine and caffeine are two compounds commonly found in tea. Theanine is an amino acid known for its relaxing properties, while caffeine is a stimulant that enhances alertness. When consumed together, these compounds have been shown to influence various cognitive and physiological functions.
Cognitive Performance and Attention
Improved Cognitive Performance
Several studies have demonstrated that the combination of theanine and caffeine can enhance cognitive performance. For instance, the combination has been shown to improve accuracy during task switching and increase self-reported alertness while reducing tiredness . Additionally, it has been found to improve total cognition composite scores and target discriminability in attention tasks 134.
Enhanced Attention and Reduced Mind Wandering
Theanine and caffeine together have been shown to improve sustained attention and reduce mind wandering. This combination decreases task-related reactivity in brain networks associated with mind wandering, such as the default mode network, thereby enhancing focus on tasks 1410. The combination also leads to faster reaction times and improved accuracy in visual attention tasks 25.
Mood and Emotional Arousal
Mood Enhancement
The combination of theanine and caffeine has been found to positively affect mood. It reduces self-reported mental fatigue and increases feelings of alertness . Moreover, theanine can counteract the jitteriness and increased blood pressure caused by caffeine, leading to a more balanced mood state 68.
Effects Under Emotional Arousal
Under conditions of emotional arousal, theanine and caffeine exert opposite effects on attention. Caffeine enhances global processing of visual attention, while theanine enhances local processing. When combined, these effects neutralize each other, resulting in no significant difference from placebo .
Physiological Effects
Blood Pressure and Heart Rate
Theanine has been shown to mitigate the increase in blood pressure caused by caffeine. This interaction suggests that theanine can help reduce the physiological stress responses typically associated with caffeine consumption 68.
Neural Resource Allocation
Functional magnetic resonance imaging (fMRI) studies indicate that theanine and caffeine together decrease neural resource allocation to distractors, allowing for more efficient attention to target stimuli. This effect is likely due to the synergistic action of the two compounds in reducing mind wandering and enhancing focus .
Conclusion
The combination of theanine and caffeine offers a unique blend of cognitive and physiological benefits. It enhances cognitive performance, improves attention, and positively affects mood while mitigating some of the adverse effects of caffeine, such as increased blood pressure and jitteriness. These findings suggest that theanine and caffeine together may be a beneficial supplement for improving cognitive function and managing stress.
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Most relevant research papers on this topic
Effects of l-theanine–caffeine combination on sustained attention and inhibitory control among children with ADHD: a proof-of-concept neuroimaging RCT
L-theanine and caffeine combination may improve sustained attention, inhibitory control, and overall cognitive performance in boys with ADHD.
The effects of l-theanine, caffeine and their combination on cognition and mood
L-theanine and caffeine together improve cognitive performance and reduce mental fatigue, suggesting a different pharmacological profile than caffeine alone.
L-theanine and caffeine in combination affect human cognition as evidenced by oscillatory alpha-band activity and attention task performance.
L-theanine and caffeine combined improve attention task performance and overall cognitive performance, while caffeine alone shows no effects.
L-theanine and Caffeine Improve Sustained Attention, Impulsivity and Cognition in Children with Attention Deficit Hyperactivity Disorders by Decreasing Mind Wandering (OR29-04-19).
L-theanine and caffeine improve sustained attention and overall cognitive performance in children with ADHD, potentially by decreasing mind wandering during attention effort.
Acute effects of theanine, caffeine and theanine–caffeine combination on attention
Theanine and caffeine have additive effects on attention in high doses, with theanine improving cognitive functions and caffeine enhancing neurophysiological responses.
Time for tea: mood, blood pressure and cognitive performance effects of caffeine and theanine administered alone and together
Theanine, found in tea, may help reduce blood pressure and may explain the perceived differences between tea and coffee.
Caffeine and theanine exert opposite effects on attention under emotional arousal.
Under emotional arousal, caffeine and theanine have opposite effects on attention, but when consumed together, they counteract each other's effects.
A double-blind, placebo-controlled study evaluating the effects of caffeine and L-theanine both alone and in combination on cerebral blood flow, cognition and mood
Combining L-theanine with caffeine at levels equivalent to one to two cups of tea eliminates the vasoconstrictive effect and behavioral effects of caffeine, but does not have a positive impact on behavior.
The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness
A combination of 97 mg L-theanine and 40 mg caffeine improves cognitive performance and increases subjective alertness in young adults, while reducing self-reported tiredness.
l-Theanine and caffeine improve target-specific attention to visual stimuli by decreasing mind wandering: a human functional magnetic resonance imaging study.
L-theanine and caffeine supplements improve attention to visual stimuli by increasing neural resource allocation to target stimuli and decreasing deviation of attention to distractors.
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