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L-Theanine and Caffeine: A Balancing Act of Energy

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Think of the perfect combinations in life. Peanut butter pairs well with jelly, burgers are nothing without fries, and even hot chocolate needs a few mini marshmallows to render the winter treat complete. Alone these items are just fine — everyone loves a plate of French fries, after all. But when combined with one another, suddenly they come alive in untold ways.

Just as we find ourselves looking for culinary combinations, researchers examining the foods we eat for health combinations. An area of research in which we’ve made progress concerns the class of drugs known as nootropics.

The word may sound intimidating, so let’s break it down: Nootropics are any drug, supplement, or substance that has the ability to improve cognitive function. Such improvements can relate to memory, creativity, motivation, intelligence, and beyond.

So which nootropics make for the perfect pair? Of the many nootropics that improve cognitive function and may complement one another, none are a better match than L-theanine and caffeine. Before we can discuss the benefits of caffeine and L-theanine, however, let’s look at their best qualities as individuals. Let’s start with the nootropic we know and love (and sometimes hate), caffeine.

Caffeine: America’s Favorite Nootropic

Most of us have a love-hate relationship with caffeine. Sure, we need it in our morning cup of Joe to jump start our day, but we hate admitting how dependent we are on its energetic powers. Caffeine is found in over 60 plants around the world. We can find it in tea plants, tea leaves, kola nuts, and cacao.

And while caffeine is found naturally in many places, it’s also produced synthetically and added to foods, medicines, and drinks. Though the amount of caffeine can vary greatly between substances, the average 8 oz cup of coffee contains 95-200 mg of caffeine.

So how exactly does caffeine work? In order to function as a cognitive stimulant, caffeine assumes an interesting role in our brain that keeps us going should we ever grow tired.

As neurons fire endlessly in our brain throughout the day, a neurochemical called adenosine will build up over time and reduce neuronal activity. This will cause us to feel sluggish, dull, and far less alert as the day progresses.

But caffeine comes to the rescue because it can mimic adenosine and prevent it from slowing down those important neurons. This is why we receive a boost of energy when we consume caffeine — it stops our brains from growing lethargic.

As any coffee drinker can testify, caffeine produces a number of side effects in the body that range from good to bad. It can stimulate the nervous system and make us alert, while also boosting working memory and even decreasing the odds of specific cancers.

Caffeine can increase our reaction time and improve cognitive performance. But it can also raise our blood pressure, increase our heart rate, produce those classic caffeine jitters, or lower sleep quality. The effects of caffeine are dependent on how much we consume and how often.

Should we choose to drink tea to get our caffeine instead of coffee, chances are we’ve already associated with caffeine’s perfect partner, L-theanine.

L-Theanine: The Amazing Amino Acid

L-theanine is an amino acid found primarily in specific plants. Of the plants we consume most often, we can find L-theanine in green tea, black tea, and certain mushrooms.

Taken to reduce anxiety and depression, L-theanine performs similar actions to gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter that blocks excitatory responses in the brain. L-theanine blocks these excitatory responses. As a result, it can lower blood pressure, decrease heart rate, and reduce stress hormone levels in the body.

A typical cup of brewed black tea will contain approximately 24 mg of L-theanine, while a typical cup of brewed green tea will contain 8 mg of L-theanine. The cup of tea we choose to consume will determine the effects of L-theanine, as certain teas contain more L-theanine than others.

As we’re winding down in the evening, L-theanine can also help us sleep by generating alpha brain waves that are associated with relaxing activities such as daydreaming and meditation. Yet oddly enough, it can also help us maintain focus when we begin our day. A systematic review found that subjects performed attention tasks better after supplementing with L-theanine.

L-Theanine and Caffeine: How They Work Together

Now that we’ve gained a basic understanding of both caffeine and L-theanine as individual nootropics, it’s time to discuss why these two make for the perfect combination.

Think, for a moment, of the many drawbacks related to caffeine. It causes stress, anxiety, restlessness, and even increases blood pressure. As the perfect partner, L-theanine works to correct these negative qualities, thus ensuring our caffeine intake experience is far more pleasant.

Because caffeine replaces adenosine in the brain, our minds are stimulated and running a bit too free. But when we add L-theanine to the conversation, that excitatory response is inhibited, and stress is managed as a result.

Additionally, L-theanine will eliminate caffeine’s ability to constrict blood vessels, so increased heart rate and blood pressure are no longer an issue. Clinical trials from a 2008 study conducted by Owen GN showed fewer headaches and less tiredness when subjects mixed the two nootropics, compared to consuming caffeine on its own. It’s as if we’re consuming caffeine without the negative side effects we often encounter.

But the combined effects of L-theanine and caffeine don’t simply stop at addressing physiological stress responses. Research conducted by Crystal Haskell and her colleagues at Northumbria University showed that a combination of L-theanine and caffeine improved reaction times for delayed word recognition.

Additionally, in a 2017 study, subjects reduced the amount of time it took to respond to flashing light cues on a computer, which suggested an improvement in acute attention.

Yet as with most combinations in life, not every aspect of the L-theanine and caffeine combination is entirely harmonious. While some studies have shown promising results, others have been unable to reproduce the same results under similar conditions.

For example, one study found there to be no significant increase in subject alertness at all. Others have postulated that L-theanine may even mitigate caffeine’s cognitive benefits.

There are also some important medical cautions worth noting. L-theanine should not be combined with blood pressure medications because L-theanine naturally reduces blood pressure.

Caffeine should not be taken with stimulant drugs because these work similarly to caffeine, and may fatigue our central nervous system when combined. Always consult a medical healthcare professional before starting supplements in any form.

We Make a Great Pair

While some research suggests a combination of L-theanine and caffeine produces no health benefits, most results have remained promising. For those looking to increase cognitive function or simply calm the caffeine jitters, combing these nootropics may be the answer.

Take some time to understand how these nootropics work within the body, consult the proper medical professionals, and reap the benefits that may follow. When the stimulating effects of caffeine are matched by the calming support of L-theanine, a productive and fruitful day is on the way.

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