Stacking L-Theanine and caffeine is one of the most popular combinations among users of nootropics. The synergistic connection between the two supplements is well known, and not just to the nootropics fans.
L-Theanine was originally paired with caffeine by nature, in the form of green tea leaves. Green tea fans have long espoused the beverage’s unique blend of clear focus and relaxation.
Unlike coffee, which can produce jitters, hyperactivity, and an inevitable crash after its initial energy boost, green tea is balanced and gentle. Now, we are able to use its key component L-Theanine as a nootropic supplement. Here’s how taking L-Theanine with caffeine can enhance the benefits of both compounds.
L-Theanine is available as a dietary supplement only, and the FDA has not approved L-Theanine as a drug to prevent or treat any conditions.



- Supports focus, attention & mood
- Helps to reduce stress & anxiety
- Neuroprotective & increases NGF
What is L-Theanine?
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L-Theanine, similar in structure to L-Tryptophan, is a natural amino acid which is found in tea leaves and some mushrooms.
Able to cross the blood-brain barrier, L-Theanine as a nootropic is a psychoactive agent that interfaces with neuroreceptors and stimulate the production of certain neurotransmitters.
An analog to L-Glutamine, L-Theanine is able to spur several key inhibitory reactions in the brain. It promotes GABA production, which blocks excessive stress messages, and generates alpha waves – electrical impulses which accompany a calm, extremely relaxed state.
At lower doses – around 50-100 mg per day – L-Theanine creates a sensation of mental focus and attentiveness. It is often used at this dose to subtly sharpen senses and improve sleep.
At higher doses, between 200 and 400 mg per day, L-Theanine can have a dramatic calming effect, creating a feeling of mellow confidence and tranquility. At this dosage, many people use L-Theanine as a nootropic for anxiety and depression.
Benefits of Stacking L-Theanine and Caffeine
When used in combination, L-Theanine and caffeine create synergistic benefits which amplify and refine the effects that either compound produces on its own. Many of the drawbacks of caffeine are nullified by the inhibitory presence of L-Theanine as a nootropic, such as hyperactive energy, darting attention span, jittery muscles, and inability to rest. The cognitive benefits of the stack are dramatic.
Studies indicate the combo results in greater visual acuity, greater muscle dexterity, significantly increased mental focus, self-reported alertness, better reaction times to stimulus, better memory recall, and longer natural attention span. These kinds of amplified benefits are typical of nootropic stacks.
Figuring Out The Perfect Dose of L-Theanine and Caffeine
What is the best ratio of these two supplements? For the above-mentioned studies, the two compounds were generally combined 2 parts L-Theanine to 1 part caffeine. In general, most users report success with as much as 4 parts L-Theanine to 1 part caffeine. 400 milligrams of L-Theanine and 100 milligrams of caffeine is a popular dose amount. For reference, the average cup of regular coffee has about 100 milligrams of caffeine.
If you are already a regular coffee drinker, you may have a built-in tolerance to the effects of caffeine. This may prompt you to increase your caffeine dosage. However, even when balanced with L-Theanine, it is suggested that all users keep caffeine levels below 400 mg per day.
Above that level, caffeine may affect heartbeat and interfere with sleep cycles. Try gradually reducing daily caffeine intake for 1-2 weeks before pairing it with L-Theanine in your nootropic stack.
Safety and Side Effects
As mentioned above, caffeine does carry the risk of side effects with dosages that are too large.
In addition to potential cardiac arrhythmias and disrupted sleep, overdose of caffeine may induce nausea and diarrhea. With a half-life of 3-6 hours, these effects will gradually dissipate.
L-Theanine, on the other hand, does not have any major side effects. It is also water soluble, which means the body will easily discard the portions of the supplement it does not need, preventing the possibility of toxicity.
In combination, L-Theanine and caffeine have been noted to temper the potential side effects of caffeine alone. Still it’s a good idea to approach new combinations of supplements with caution and patience. Until you are familiar with your own body’s unique reaction to various nootropic stacks, it’s best to start with lower doses.
In the case of L-Theanine and caffeine, beginning with a 1 to 1 ratio might be a great way to establish a baseline of effects and help you differentiate benefits from a typical cup of coffee or tea. Then, gradually increase the dosage of L-Theanine, over days or weeks, until you reach the desired effect.
In this case, side effects will generally indicate that you have taken too much caffeine for your system to comfortably process. Proceeding respectfully and cautiously is always a good policy with any medications, therapies, or supplements you’ve never tried before.
However, L-Theanine as a nootropic is one of the safest natural brain-boosters on the market. The L-Theanine and Caffeine combo is considered one of the best nootropic stacks for beginners due to its safety and tolerance profile. Taken responsibly, nootropics can be a valuable mind and mood-enhancing addition to everyday life that is more beneficial then plain coffee alone.
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Article last updated on: March 18th, 2018 by Nootriment
1 Comment
Anybody else mix coffee with l theanine? If so would you buy coffee that is already mixed with it? I would…