Benefits of Taking L-Theanine With Caffeine

cup of coffee with l-theanine

If you’re someone who's had to look into getting rid of caffeine jitters, you’ve probably come across L-theanine. Taking L-theanine with caffeine is a common solution to reducing some of caffeine’s worst side effects. 

L- Theanine, or simply theanine, is an amino acid found in certain types of tea, and less frequently in some mushrooms. Research shows it has a number of potential health benefits, but avid coffee drinkers might find the most useful of these to be its ability to counteract anxiety and jitters associated with caffeine. 

In this post, we’ll discuss the efficacy of taking theanine with caffeine and how best to use it to boost results. 

What is L-Theanine? 

As mentioned, theanine is an amino acid, but it’s not naturally produced by the human body. And while it isn’t an essential amino acid, this still means it must be supplemented by your diet if you’d like to experience the benefits. 

Unfortunately, the only truly abundant, naturally occurring source of theanine is green tea. If you’re not much of a tea drinker, supplement capsules or powders are necessary. 

woman using caffeine and L-theanine to stay focused without jitters

Benefits of L-Theanine

Here are some of the common benefits of the supplement: 

  • Stress and Anxiety Relief- The most well documented benefits of l-theanine are its effects on stress and anxiety in humans. Interestingly, though reduction in anxiety is observed with theanine, there is no sedation effect as with other stress reducing supplements. This means that you can remain alert and focused on l-theanine.

  • Increased Focus- When taken with caffeine, the two have a synergistic effect increasing alertness and focus. One study showed that 40 mg of caffeine paired with 96 mg of l-theanine improved focus during a cognitive task as compared to the placebo group. 

  • Improved Immune Function- Some studies suggest that regular theanine supplementation could improve the functionality of your immune system by supporting gut health, reducing inflammation and decreasing the rate of respiratory infection

  • Better Sleep- Because theanine promotes relaxation, it’s believed to aid sleep. Research suggests taking l-theanine before bed leads to longer and more restful sleep

caffeine with l-theanine

L-Theanine and Caffeine

With all it’s standalone benefits, you should consider adding the supplement to your regular routine regardless of your caffeine intake. However, if you drink caffeinated beverages, its addition may be even more welcome. 

We're all aware of some of the drawbacks of caffeine, from headaches to jitters, anxiety and diarrhea. But most of just take the good with the bad for that much needed morning boost. 

Luckily, you might not need to experience all the negatives if you add a bit of theanine to the morning routine. Since it's an anxiolytic and has relaxant properties, this can mitigate some of the jitters and anxiousness associated with caffeine, without canceling out the stimulant properties for better focus and increased energy. 


Since supplements including l-theanine aren't regulated by the FDA, no established dose recommendations exist. Research shows it's best to use your caffeine intake as a guide. 

Those with a high caffeine tolerance that don't experience many of the negative side effects should use a 1:1 caffeine to l-theanine ratio. Those who suffer the worst effects of caffeine should adopt a 1:2 ratio, taking double the amount of caffeine as theanine. 

For example, the average cup of coffee has about 90 mg of caffeine, so depending on your tolerance, you should add either 95 mg or 190 mg of L-theanine. 

For a good pre-mixed energy supplement with caffeine and l-theanine, try out Nutriair Energy Diffuser. 


Bottom Line

For those that struggle with anxiety and jitters from taking caffeine, L-theanine could be a good solution. It's anxiety relieving and relaxant properties make it a good option for those that want the increased focus without the draw backs. 

L-theanine may also be good as a sleep aid and to boost immunity, but more research is needed. Be sure to consult your healthcare provider before adding any new supplements to your routine, as some may have negative interactions with current medications or cause allergies.