L-theanine, Catechins, & More: Drink Green Tea for Brain Nutrition

A cup of green tea may not be the first thing you reach for in your brain care routine, but it turns out that this simple addition provides more than one nutrient that can help protect your memories and keep your brain sharp.  As we’ve learned previously from the blue zone of Okinawa, Japan, it's evident that green tea offers multiple health advantages across various conditions.  In our exploration today, we'll dive specifically into its profound impact on brain health. 

From improving brain performance and mood regulation, to mitigating the risk of neurological conditions such as Alzheimer’s and Parkinson’s, green tea has garnered widespread popularity for its diverse benefits.  Read on to find out about all the ways in which green tea, including its potent variant matcha, contributes to better brain health. 

What Green Tea Does for Your Brain: 

Helps Your Focus and Attention:  Studies indicate that consuming green tea can lead to an increase in alpha, beta, and theta brain waves, particularly observed an hour after ingestion.  These wave patterns suggest improved cognitive functions, including improved focus and attention.1  

Furthermore, green tea contains caffeine, complemented by L-theanine.  This combination has been shown to yield beneficial effects on sustained attention, memory retention, and the ability to suppress distractions.2 

Easier to Relax:  Green tea helps reduce stress because of two important nutrients in it: Epigallocatechin gallate (EGCG) and L-theanine.  EGCG has calming effects, while L-theanine increases a chemical called GABA in the brain.  More GABA can help slow down brain activity, making you feel calmer and more at ease.3  

Improves Your Sleep:  L-theanine, a nutrient found in green tea, has been found to boost serotonin and dopamine, which are neurotransmitters crucial for sleep.  Serotonin helps regulate the sleep-wake cycle and promotes relaxation, while dopamine contributes to alertness during the day and may aid in maintaining sleep continuity at night.  Together, they help promote overall sleep quality.3 

Better Memory:  Studies have found that green tea can improve memory by enhancing brain cell communication and increasing dopamine levels in the hippocampus, a brain region important for memory.1

Reduces the Risk of Alzheimer’s & Parkinson’s Disease:  Research suggests that green tea and its compounds, which are high in antioxidants, can reduce inflammation and oxidative stress in the brain, and protect against neurodegenerative diseases.  It also activates protective pathways in the brain and may help reduce the buildup of beta-amyloid, a protein associated with Alzheimer's disease.  Drinking green tea may also help protect the brain from damage and reduce the risk of diseases like Parkinson's.1 

The Role of Green Tea Nutrients in Your Brain: 

Now that you're familiar with the array of benefits you may experience from drinking green tea, let’s understand why you should be thankful for the rich nutrient profile. 


Catechins are a type of natural compound found in tea leaves.  They belong to a group of polyphenols known as flavonoids, which are renowned for their antioxidant properties and health benefits.  As Medical Advisor, Dr. Annie Fenn from Brain Health Kitchen mentioned in her recent substack, green tea provides the highest polyphenol count of all teas.  

Catechins may improve blood flow to the brain, which can provide better delivery of oxygen and nutrients to brain cells.  Research suggests that catechins may also play a role in promoting brain health and cognitive function by supporting neuroplasticity (the brains ability to adapt and change) and by reducing neuroinflammation.4


L-Theanine is a natural amino acid abundant in green tea, known for its calming effects on both the mind and body.   

It achieves this by modulating neurotransmitter activity, such as gamma-aminobutyric acid (GABA), serotonin, and dopamine, which regulate mood and stress response.  It exhibits neuroprotective properties, guarding against oxidative stress and inflammation, potentially benefiting brain health and cognitive function.5  L-Theanine also supports Brain-derived Neurotrophic Factor (BDNF), a protein vital for neuron growth and function, thereby maintaining brain plasticity essential for learning, memory, and cognitive flexibility.6


Quercetin is a flavonoid found most abundantly in matcha green tea, known for its antioxidant and anti-inflammatory properties.  Studies indicate that quercetin promotes neurogenesis, improving memory and learning, while also preventing brain cell death in the hippocampus.  Moreover, it promotes energy balance and mitochondrial production, vital for brain cell survival and function.  Recent research also suggests its role in reducing inflammatory markers in the case of the APOE4 gene and inhibiting harmful inflammatory responses in the brain.7  

Read our full article on quercetin’s brain benefits here.  

How Much Tea Should You Drink? 

You might be wondering if you need to swap out all your beverages for green tea to reap the benefits mentioned above.  However, even incorporating just one cup a day can offer significant nutritional value.  As a general guideline, it’s recommended to aim for 2-6 cups per day to maximize the potential benefits.  Considering that green tea contains caffeine, you may want to avoid consuming it in the late afternoon and evening hours to support a good night's sleep.   

If incorporating tea into your daily routine feels challenging or you're not particularly fond of it, supplementation can offer a convenient alternative while still providing the nutrients mentioned above.  Our brain health supplement, RELEVATE, includes key ingredients like L-theanine, catechins, and quercetin.  The doses of these nutrients in RELEVATE are formulated to mimic what you would naturally consume through tea or other food sources, helping you receive optimal benefits without excessive doses.  It's an easy and effective way to support your brain health, even if tea isn't your beverage of choice.  Learn more about RELEVATE by visiting here 

For the month of May, we've upgraded our Brain Healthy Nutrition Starter Pack with matcha from Mizuba Tea Co. Sourced from a 100-year-old farm in Japan, this matcha is high in brain-protective nutrients, with a delicate flavor profile, with notes of toasted vanilla and creamy butter.  Plus, the Bamboo Matcha Scooping Spoon by Mizuba Tea Co., adding a touch of elegance to your tea rituals with its precise measurement.   Along with Medical Advsior Dr. Annie Fenn’s Brain Health Kitchen Cookbook, with recipes to inspire you to cook with matcha, and 100+ other brain healthy recipes. Paired with two bottle of RELEVATE, it can help you begin your journey to a lifetime of brain health.  Learn more and order here. 

To hear more on the latest news on prevention and brain health, subscribe to our newsletter here.   


  1. Akbarialiabad, H., et al. (2021). Green Tea, A Medicinal Food with Promising Neurological Benefits. Current Neuropharmacology, 19(3), 349. https://doi.org/10.2174/1570159X18666200529152625
  2. Dietz, C., & Dekker, M. (2017). Effect of Green Tea Phytochemicals on Mood and Cognition. Current Pharmaceutical Design, 23(19), 2876–2905. https://doi.org/10.2174/1381612823666170105151800
  3. Unno, K., et al. (2018). Stress-Reducing Function of Matcha Green Tea in Animal Experiments and Clinical Trials. Nutrients 2018, Vol. 10, Page 1468, 10(10), 1468.
  4.  Afzal, O., et al. (2022). Green Tea Catechins Attenuate Neurodegenerative Diseases and Cognitive Deficits. Molecules, 27(21). https://doi.org/10.3390/MOLECULES27217604https://doi.org/10.3390/NU10101468
  5. Saeed, M., et al. (2017). Green tea (Camellia sinensis) and l-theanine: Medicinal values and beneficial applications in humans-A comprehensive review. Biomedicine & Pharmacotherapy = Biomedecine & Pharmacotherapie, 95, 1260–1275. https://doi.org/10.1016/J.BIOPHA.2017.09.024
  6. Sbrini, G., et al. (2020). Centella asiatica L. Phytosome Improves Cognitive Performance by Promoting Bdnf Expression in Rat Prefrontal Cortex. Nutrients, 12(2). https://doi.org/10.3390/NU12020355
  7. Understanding the Brain Health Benefits of Quercetin – NeuroReserve Inc. (n.d.). Retrieved May 6, 2024, from https://neuroreserve.com/blogs/articles/understanding-the-brain-health-benefits-of-quercetin
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