Drinking tea may improve memory and help protect against Alzheimer’s and dementia. According to a Japanese study, elderly volunteers who consumed green tea showed a significantly lower decline in cognitive function when compared to a placebo group.
The researchers focused on a compound in tea called “theanine.” Theanine resembles glutamate, a neurotransmitter related to memory. They found that once theanine passes through the blood-brain barrier, it exerts a brain-protective effect. They also found that theanine helps prevent cell death after a mini-stroke.
Other studies suggest that the combination of theanine and caffeine may improve cognitive function. In particular, a dose of theanine and caffeine before a demanding cognitive task may significantly improve accuracy and alertness. Theanine has been shown to reduce mental and physical stress, improve cognition, and boost mood in a synergistic manner with caffeine.
So what teas have the most L-theanine? Gyokuro contains the highest levels, 2% by dry weight. Gyokuro is a shade grown green tea that is high in antioxidants. Gyokuro forms the base of our Izu Matcha, Bilberry Matcha, and Samurai Matcha. Matcha teas are powdered, and thus infused directly with water or in smoothies. This provides the highest concentration of beneficial compounds.
Teas that are minimally oxidized posses high levels of L-theanine as well. Our line of white teas are the least oxidized, followed by our line of green teas.
Oolong and black teas possess the least amount of L-theanine. However, these oxidized teas provide other beneficial compounds not present in green or white tea.
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