1. Focus & Concentration
Both caffeine and L-Theanine have been shown to improve focus and concentration through separate mechanisms.
Caffeine works primarily through its ability to stimulate the brain and induce a state of wakefulness when we would normally feel tired or mentally fatigued.
The effects of L-Theanine are a little bit more complex and researchers are still striving to understand exactly how L-Theanine is so useful for promoting a state best described as a “clear headed focus”.
Studies on L-Theanine were conducted with the help of a device capable of measuring electrical activity in the brain - known as an electroencephalogram (EEG). These studies have repeatedly shown that L-Theanine can induce what’s referred to as alpha- brain wave activity. Past research involving EEG machines have shown that alpha brain waves are associated with productive learning, as well as states of alertness but mental relaxation.
Conversely, beta wave activity is correlated with states of anxiety, stress, and conflicted mental processing, while theta waves are only present while we’re asleep or in deep meditation.
The ultimate goal while studying or working is to enter a focused state involving alpha brain wave activity.
2. Reducing the Side-Effects of Caffeine
Caffeine works by outcompeting a compound in the brain known as adenosine.
As we go through our day, adenosine levels begin to build up in the brain as a result of normal neurological processes. As adenosine levels rise, it causes the electrical activity in the brain to slow down, making us feel tired.
Caffeine blocks the effects of adenosine to delay the onset of fatigue in the brain.
Additionally, caffeine activates our adrenergic receptors in the brain. These receptors cause direct stimulation throughout the body, causing our heart rate to increase, muscles to contract, and forces our brain into a state of activation and stimulation.
Too much adrenergic activation can make us feel anxious and causes our heart to feel like its missing beats or is about to beat straight out of our chest.
The most abundant stimulatory neurotransmitter in the brain — glutamate — is activated by the adrenergic effects of caffeine. It’s the neurotransmitter responsible for carrying out many of the effects triggered by caffeine.
L-Theanine is perfectly equipped for offsetting these side-effects because it resembles the shape of glutamate very closely — close enough to bind to glutamate receptors, but not close enough to activate them.
In basic terms, L-Theanine does what Caffeine does to adenosine, it out competes it by taking residence on the receptors to block its effects.
The result is an inhibition of adenosine (and therefore sleepiness) from the caffeine, without the side effects of excessive glutamate activation.