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< class="article__title title cognitive-clarity-with-l-theanine-your-brain-fog-buster"> Cognitive Clarity With L-Theanine: Your Brain Fog Buster>
Cognitive Clarity With L-Theanine: Your Brain Fog Buster
Oct 28, 23
This article has been vetted by the Onnit Advisory Board. Read more about our editorial process.
Author: Sony Sherpa

Cognitive Clarity With L-Theanine: Your Brain Fog Buster

  • by Sony Sherpa

    Medically reviewed by

    Sony Sherpa

    Dr. Sony Sherpa is a board-certified Clinical Doctor and dedicated advocate for holistic medicine, specializing in functional mushrooms. Her blend of medical expertise and passion for alternative wellness lends authenticity to her role as a contributor for Natures Rise.

  • |
  • 7 min read
Cognitive Clarity With L-Theanine: Your Brain Fog Buster

L-theanine may promote mental wellness and help reduce stress. Occasional anxiety can impair brain activity and make it difficult to think clearly, concentrate, or recall information.

Additionally, it's typical to encounter changes in memory and focus as we age. If you are one of the many people who struggle with memory issues, anxiousness,  or brain fog,  you may benefit from L-theanine.

What does L theanine do in the brain? The compound supports dopamine and serotonin activity in the brain, which enhances overall attention. While this amino acid is present in both green and black tea, taking a supplement may help you obtain more of it to combat brain fog symptoms.

Below, we explore L theanine brain fog benefits.

Understanding Brain Fog

Understanding Brain Fog

The brain is the body's most intricate and enigmatic organ. A person can experience clarity, creativity, and focus all at once. Then, a hazy feeling sets in. The brain seems to be turned off for brief periods throughout the day. Everybody experiences occasional disorientation. Brain fog(1) can be problematic when this feeling interferes with relationships and work.

Memory issues, exhaustion, lack of focus, and chaotic thoughts are just a few of the symptoms that make up brain fog, which is not a medical condition. Taking supplements may be helpful.

Brain fog is frequently associated with people with specific medical issues. It can also be brought on by lack of sleep, exhaustion, stress, and lifestyle choices.

Now, what does L-theanine do to your brain? Let’s explore next.

Introducing L-Theanine

Introducing L-Theanine

L-theanine is an amino acid structurally similar to the neurotransmitters glutamate and GABA, vital for proper brain function. It can be found in black, green, and oolong teas made from the perennial evergreen shrub Camellia sinensis. L-theanine has long been used to promote relaxation without having any sedative effects.

Caffeine and L-theanine are often used for cognitive clarity. The amino acid L-theanine scores because it lowers the brain waves that influence anxiety and nervousness, whereas caffeine is claimed to have a stimulating effect but is also linked to increased nervousness in sensitive people.

L-theanine effects on the brain

L-theanine effects on the brain

L-theanine can enhance focus, memory, and attention, all aspects of cognitive functioning. L-theanine could help reduce anxiety and help with mood improvement, in addition to being neuroprotective. Additionally, it decreases tiredness and brain fog, promoting optimum mental function.

L-theanine may influence mood

Gamma-aminobutyric acid (GABA), glutamic acid, and other neurotransmitters can significantly impact mood modulation. L-theanine(2) is thought to influence mood similarly. The amino acid interacts with the brain's dopamine and serotonin neurotransmitter systems to provide anxiolytic (anxiety-reducing) and soothing effects.

The effects of L-theanine supplements and placebos were examined in a review(3) of five randomized controlled studies. Researchers discovered that when subjects were exposed to scenarios that caused psychological stress, L-theanine could lower anxiety and tension.

L theanine improves memory

Another study(4) of 69 adults between the ages of 50 and 69 discovered that a single dose of 100.6 mg of L-theanine enhanced working memory and reaction time on cognitive tests. The Mini-Mental State Examination was used in this study to evaluate cognitive fiction in Japanese men and women.

The participants were evaluated before taking L theanine, after a single dose, and after 12 weeks of regular intake. The study suggested that L-theanine may help increase attention, improving working memory and executive functioning.

L theanine improves cognitive functioning

Compared to a placebo, a small study(5) indicated that 200 mg of L-theanine per day might reduce the symptoms of stress, improve sleep, and improve some aspects of cognitive function. Eliminating stress, enhancing sleep, and promoting cognitive health relieve brain fog.

L-theanine can interact with numerous other hormones and brain functions since it can pass through the blood-brain barrier. It is thought to reduce corticosterone levels(6), inhibiting the formation of memories and some types of cognitive functions.

The amino acid also enhances cognitive processing by influencing alpha brain wave(7) activity. Each of the five different types of brain waves represents a different degree of brain activity, and alpha waves indicate a calm and relaxed state.

How to Use L Theanine for Brain Fog

How to Use L Theanine for Brain Fog

A relaxing tea ritual is an excellent place to start if you're interested in exploring more about the cognitive benefits of L theanine. However, tea has less L-theanine than most supplements, so supplementing may be a good idea. L theanine supplements are available as liquids, capsules, powders, and tablets.

Potential Precautions and Considerations

Potential Precautions and Considerations

Large-scale meta-analyses of L-theanine use over time have revealed minor adverse effects. L-theanine supplementation (400 mg/day) was well tolerated(8) in a short study with no harmful side effects. Anecdotal evidence suggests that a tiny number of users have experienced minor issues like headaches, nausea, dizziness, and diarrhea.

There are no explicit, scientifically supported guidelines for the recommended supplement dosage. Most specialists advise starting modestly, with about 100 mg of L-theanine daily, and increasing as necessary. A majority of clinical research that focused on the amino acid used doses between 100 and 300 milligrams.

Speaking with a healthcare professional before using L-theanine is a good idea. The safety of L-theanine for pregnant or breastfeeding women has not been established by research, so they should avoid use.

FAQs About L Theanine Brain Fog

Does L-Theanine Help With Focus?

According to research, L-theanine may have several health benefits, some of which may include increased mental clarity. The amino acid also alleviates mental fog.

When Is The Best Time To Take L-Theanine For Managing Brain Fog?

Your requirements and preferences will determine the ideal time to take L-theanine. Taking it in the morning or early afternoon may help improve focus.

Can L-Theanine Be Combined With Other Supplements Or Medications For Brain Fog Management?

No known dangerous interactions exist between L-theanine and particular drugs or dietary supplements.  However, as the amino acid may lower blood pressure, it may be best to avoid use with anti-hypertensives.

Key Takeaways

L-theanine is frequently used to decrease the effects of stress and anxiety and improve concentration and brain function.  Additionally, it might ease stress and promote relaxation and calmness.  Before using L theanine for brain fog, speak with your healthcare provider to get the most out of it.

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  1. Brain “fog,” inflammation and obesity: key aspects of neuropsychiatric disorders improved by luteolin, (1) 
  2. Mechanisms Underlying the Anti-Depressive Effects of Regular Tea Consumption, (2) 
  3. Theanine consumption, stress and anxiety in human clinical trials: A systematic review, (3) 
  4. Effects ofl-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study, (4) 
  5. Effects of Chronic L-theanine on Stress-related Symptoms and Cognitive Function in a Non-clinical Population: A Randomized Controlled Trial (P06-106-19), (5) 
  6. Protective effect of l-theanine on chronic restraint stress-induced cognitive impairments in mice, (6) 
  7. The effects of L-theanine on alpha-band oscillatory brain activity during a visuo-spatial attention task, (7) 
  8. The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial, (8)

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