L-Theanine and Caffeine

L-theanine and Caffeine


L-Theanine and caffeine is one of the most powerful and impressive supplement combos. Here we take a comprehensive look at everything involving this combination, including how it works, the dosage and ratios, how to take it most effectively, and all the different benefits and uses.

What is L-Theanine and Caffeine used for?

These 2 are taken together for a variety of reasons.

Benefits/Uses for L-Theanine and Caffeine combo:

  • Increase overall mental focus
  • Increase concentration and attention span
  • Increase productivity at work
  • Help with studying for exams
  • Improve mood
  • Improve reaction time
  • Mitigate or take away the nervous/jittery effects of coffee
  • Improve sense of alertness
  • Decrease feeling of sleepiness

Note: More and more people are taking the “l theanine + caffeine” combo to help with their ADHD or ADD symptoms.  So this supplement combo is a very interesting idea to consider as a potential alternative. For more info, we also researched and wrote about supplements for ADHD.

What are the scientific studies for the l-theanine and caffeine combo?

A)  This study looked at the effects of l-theanine and caffeine on mood, cognition, and blood flow.

B)  Here is another study that looked at the effects of l-theanine and caffeine on mood and cognition. 

It concluded that:

“L-theanine and caffeine in combination are beneficial for improving performance on cognitively demanding tasks.”

C)  This study showed that the combination of l-theanine and caffeine improves cognitive performance and increases subjective alertness

How does L-Theanine and Caffeine work?

L-Theanine plus caffeine is a truly synergistic supplement combination. This means that the two supplements work better when taken together than either work alone. They also enhance each other’s benefits.

Let’s start with caffeine.

Caffeine is a stimulant. Most of us are familiar with how a strong morning cup of coffee feels. Here is how it works.

The caffeine molecule has a very similar size and shape to the neurotransmitter adenosine.
Adenosine makes us feel very sleepy when it binds to the adenosine A1 receptor.

Caffeine works by absorbing quickly into the blood and sneaking into the adenosine A1 receptors first, before the real adenosine neurotransmitter has a chance to act.

This means that adenosine can’t work properly because caffeine is already bound to the A1 receptors, “clogging” them up. So the adenosine just builds up in the brain but doesn’t cause sleepiness since it has no receptor site to act upon.

And not only does the caffeine block the sleepiness signals which adenosine normally sends, but this entire situation also sends messages to the brain causing the release of adrenaline (epinephrine), giving us a sustained jolt of energy in addition to the lack of sleepiness.

Also, the excitatory neurotransmitters, glutamate and dopamine, are freed up to work more effectively, giving us even more energy and sense of alertness.

In a nutshell, caffeine blocks our ability to feel sleepy, it causes the release of adrenaline, and it makes dopamine and glutamate more effective in stimulating us.

Caffeine increases adrenaline, increases cortisol, constricts the blood vessels, increases our heart rate, and puts us in the “fight or flight” state.

So caffeine by itself is very impressive in giving us a heightened sense of awareness, focus, concentration, and wakefulness.

BUT, it’s also not a very “clean” form of energy. It can make us very anxious, nervous, and jittery. This is a big price to pay for being “awake and aware”.

L-Theanine is great for helping to lessen the negative effects of caffeine, while increasing the effectiveness of the positive effects.

** Here is some more info on how caffeine works:

How Caffeine works
What Caffeine does in your brain

Now let’s look at L-Theanine.

L-Theanine is an amino acid which absorbs and works immediately. It’s quickly gaining popularity as a supplement because it works so incredibly well too.

L-Theanine increases GABA, and GABA’s effectiveness in the brain. GABA is the body’s main inhibitory neurotransmitter.

GABA is the most prevalent neurotransmitter in the human body with over 40% of neurons having GABA receptor cites. Once a GABA molecule attaches to its receptor, it tells the neuron to “stop firing” or basically shut down.

This effect of stopping the excess neuronal firing is very calming and great for reducing the jitters and anxiety from excess caffeine.

Anxiety is one negative side effect from too much neuronal firing in the brain. The out-of-control thoughts, the needless worry, the pointless panic and fear are from too many neurons firing in the wrong places. L Theanine helps to physically shut down and slow down those signals very quickly.

L Theanine also increases alpha brain wave activity. Alpha brain wave activity is very high during REM sleep and during deep states of mental relaxation and concentration. Alpha brain waves are also high in Zen Buddha masters while they are practicing deep meditation.

So the increase in the effectiveness of GABA from L Theanine helps us remain calm and anxiety/jitter free, thus mitigating the negative effects of caffeine.

The increased alpha brain wave activity helps us to concentrate, focus, and get a job done while still being anxiety free.

In conclusion, the overall effects of L Theanine and caffeine taken together are:

  • Increased adrenaline (Increasing energy)
  • Increased dopamine and glutamate (energy and alertness)
  • Decreased effectiveness of adenosine (Decreasing sleepiness)
  • Increased GABA (Lowering anxiety and nervousness)
  • Increased alpha brain wave activity (Improving focus/concentration)

This all combines to increase energy, decrease sleepiness, increase mental focus and concentration, decrease anxiety, decrease nervous jitters.

The exact effects depend on the person taking the combo AND on the doses and the ratios of the supplements. See below.

Dosage and Ratio

This is a very subjective question and the ratios and dosages really depend on the person and the purpose of use.
Remember, L Theanine is more relaxing and caffeine is more stimulating. So if you’d like more of an energizing feeling, then try a higher % of caffeine. If you’d like a more relaxing or calming type of focus, then opt for more L Theanine.

Some standard ratios people often try are:

  • 2:1 L Theanine to Caffeine
  • 1:1 Equal parts of each
  • 1:2 L Theanine to Caffeine

As for dosages, this also really depends on the person. We offer a full 250 mg of L Theanine in our premium product. A great place to start is one cup of coffee and one 250 mg capsule.

What else can combine with L Theanine and Caffeine?

If you are taking L Theanine together with caffeine to increase your concentration and focus, you may also wish to try:

If you taking caffeine + l theanine to reduce stress and anxiety, alleviate depression, and improve mood, you may wish to try:

How to take:

  • With morning coffee
  • With tea
  • With anhydrous caffeine powder blends (if you don’t like tea or coffee)

We personally prefer a premium quality, high purity L Theanine supplement along with coffee or tea rather than using a caffeine supplement. The reason is that it’s easier to control the amount of caffeine you are getting. If you want more caffeine, then brew a stronger cup of coffee, if you want less, then simply have tea or just a small cup of coffee.

Try out our pharmaceutical grade L-Theanine. We think you’ll love it.

We also have an energy supplement that has caffeine, l-theanine, and rhodiola for an extra boost.


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