GURU Theanine Fruit Punch - 3 Things You Need to Know

GURU Theanine Fruit Punch - 3 Things You Need to Know

Here are three things you need to know about GURU Theanine Fruit Punch:


1. It works: GURU Theanine is proven to improve focus and mental performance with its blend of caffeine and L-Theanine.


What if a beverage could let you access more of your brain? Our all-new GURU Theanine Fruit Punch does just that, and it’s all thanks to L-Theanine (pronounced L-thee-a-nine), a key molecule found in green tea. When blended with caffeine (and we have the right amount at 100 mg of theanine and 100 mg of caffeine), this plant-based brain food creates a synergistic effect that powers up your brain and boosts your focus and mental performance. In fact, hundreds of studies have proven the effectiveness of L-Theanine combined with caffeine. Read more about the science behind the punch here.


2. It tastes amazing: GURU Theanine is bursting with fruit punch flavour.


On top of packing a brain boost, GURU Theanine Fruit Punch is also a wake-up call for your tastebuds. It’s jam-packed with an all-natural fruit punch flavour — a simply delicious blend of fruity red berries, sweet cherry and vanilla, and the zesty freshness of yuzu.


3. It’s low in sugar and organic


GURU Theanine is low in sugar and was formulated based on our latest success, GURU Guayusa Tropical Punch. We're able to achieve low sugar and great taste thanks to our secret recipe of monk fruit juice and stevia.

And as with all GURU drinks, GURU Theanine Fruit Punch is certified organic, and contains no synthetic caffeine, artificial sweeteners, synthetic preservatives or artificial colours and flavours. All in all, it’s the refreshing boost your brain has been waiting for — and with only 50 calories.

The science behind the punch


L-Theanine was discovered in tea leaves (camellia sinensis) by Japanese researcher Yajiro Sakato in 1949 in Kyoto, Japan. L-Theanine is present in green, black and white tea, as well as in certain varieties of fungi.

The brain food that is trending the most at the moment, L-Theanine, is an amino acid that is known to act similarly to a neurotransmitter in the brain, improving mood, focus and concentration. Here are some scientific reasons why:

  1. L-Theanine increases the amount of GABA in the brain as well as its effectiveness. Higher levels of GABA are associated with calmer mental states and lower levels of anxiety.

  2. Increased Alpha brain wave activity has also been observed, enhancing focus and creativity. These brain waves are largely present during extremely calm, yet focused, mental states.

  3. L-Theanine is also well known for decreasing the negative and jittery effects of caffeine. The L-Theanine contained in tea makes us feel calmer and less jittery than coffee.

L-Theanine is also believed to help regulate dopamine and serotonin levels. Serotonin is known as the feel-good neurotransmitter, while dopamine is associated with the reward circuit.

What the research says about the combination of L-Theanine and caffeine


There have already been several decades of international research and reporting on the use of L-Theanine in terms of both safety and efficacy. Of course, caffeine alone is already proven to temporarily help promote alertness and wakefulness, to enhance cognitive performance and to support and promote mental sharpness and attentiveness[1][2][3].

As for the usefulness of the combination of L-Theanine and caffeine, there is a solid body of scientific evidence to support the claim that the combination of caffeine and L-Theanine has been shown to improve cognitive performance. Research has shown that:

  1. The combination of L-Theanine and caffeine improves both the speed and accuracy of performance when it comes to attention-switching tasks, as well as focus, as it reduces susceptibility to distracting information in memory tasks.[4]

  2. 97 mg of L-Theanine in combination with 40 mg of caffeine helps to focus attention during a demanding cognitive task (each GURU Theanine can contains 100 mg of theanine and 100 mg of caffeine).[5]

  3. In addition to improving rapid visual information processing (RVIP) accuracy and mental fatigue ratings, the combination also leads to faster simple reaction time, faster numeric working memory reaction time and improved sentence verification accuracy. Headache and tired ratings are reduced, while alert ratings are increased.[6]

  4. L-Theanine clearly has a pronounced effect on attention performance and reaction time response in normal healthy subjects prone to high anxiety.[7]

So if you find yourself needing more focus, whether it’s for your next big game, your end-of-semester exam or your Monday morning business presentation, GURU Theanine Fruit Punch is here to help sharpen your mind and get you right back on track, one delicious punch at a time.



[1] Christopher G, Sutherland D, Smith A. Effects of caffeine in non-withdrawn volunteers. Human Psychopharmacology 2005;20(1):47-53.

[2] Kamimori GH, Penetar DM, Headley DB, Thorne DR, Otterstetter R, Belenky G. Effect of three caffeine doses on plasma catecholamines and alertness during prolonged wakefulness. European Journal of Clinical Pharmacology 2000;56(8):537-544.

[3] Zwyghuizen-Doorenbos A, Roehrs TA, Lipschutz L, Timms V, Roth T. Effects of caffeine on alertness. Psychopharmacology 1990;100(1):36-39.

[4] Gail N. Owen, Holly Parnell, Eveline A. De Bruin & Jane A. Rycroft. The combined effects of L-theanine and caffeine on cognitive performance and mood.

[5] T Giesbrecht, J A Rycroft, M J Rowson, E A De Bruin. The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness.

[6] Crystal F.Haskella David O.Kennedya Anthea L.Milnea Keith A.Wesnesab Andrew B.Scholeya. The effects of L-theanine, caffeine and their combination on cognition and mood.

[7] Akiko Higashiyama, Hla Hla Htay, Makoto Ozeki, Lekh R. Juneja, Mahendra P. Kapoor.Effects of l-theanine on attention and reaction time response.

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