Stress-reducing effect of cookies containing matcha green tea: essential ratio among theanine, arginine, caffeine and epigallocatechin gallate

Abstract

The stress-reducing effect of matcha, a high-quality fine-powdered green tea, has recently been clarified by animal experiments and clinical trials. However, the effect of matcha added to confectioneries is not clear. One aim of this study was to evaluate the relationship between matcha components and their stress-reducing effect in mice that were loaded with territorially-based stress. Adrenal hypertrophy, a marker of stress, was significantly suppressed in stress-loaded mice that had ingested matcha components, displaying a caffeine and epigallocatechin gallate to theanine and arginine (CE/TA) ratio of 2 or less. Another aim was to evaluate, in humans, the stress-reducing effect of matcha in cookies using test-matcha (CE/TA = 1.79) or placebo-matcha (CE/TA = 10.64). Participants, who were fifth year pharmacy college students, consumed 4.5 g of matcha in three pieces of cookie daily for 15 days. Salivary α-amylase activity, a stress marker, was significantly lower in the test-matcha group than in the placebo group. These results indicate that the CE/TA ratio of tea components is a key indicator for the suppression of stress. Moreover, matcha with a CE/TA ratio of 2 or less displays a stress-reducing effect, even if it is included in confectionery products. Such products may also benefit individuals who have no habit of drinking matcha as a beverage.

Health Benefits and Chemical Composition of Matcha Green Tea: A Review

“…Due to the shade-growing of plants intended for matcha production, theanine does not break down. As a result, Tencha leaves contain larger amounts of it compared to other teas [ 49 ]. The relatively high theanine content in matcha tea is responsible for its unique non- bitter taste, and in combination with caffeine provides the taste sensation and umami characteristic of this type of tea [ 48 , 50 ].…”

“…The relatively high theanine content in matcha tea is responsible for its unique non- bitter taste, and in combination with caffeine provides the taste sensation and umami characteristic of this type of tea [ 48 , 50 ]. The combination of l-theanine and caffeine may enhance concentration, vigilance and efficiency to a higher extent than the use of either compound alone [ 51 ], additionally alleviating stress [ 49 ].…”

High Levels of Major Components and Antioxidant Activity of Fermented Tea Treated with Lactococcus lactis subsp. cremoris

“…Theanine (γ-ethylamide-L-glutamic acid) is an extremely rare amino acid in nature, and it has psychoactive properties because it is readily absorbed and permeates the blood-brain barrier to function in the brain [24]. This function leads to reduced mental and physical stress and improved cognition [25][26][27][28][29]. These results suggest that this fermented tea has the effect of improving brain function.…”

Effects of Daily Matcha and Caffeine Intake on Mild Acute Psychological Stress-Related Cognitive Function in Middle-Aged and Older Adults: A Randomized Placebo-Controlled Study

“…Studies on a mice model that promoted aging reported improvements in cognitive function [ 14 ] and the promotion of neurogenesis in the developing hippocampus [ 15 ]. In humans, theanine results in improved attention and reaction rates in response to cognitive tasks [ 8 , 16 ], as well as decreased α-amylase activity [ 17 ]. Theanine ingestion affects dopamine, serotonin [ 18 ], tryptophan, and gamma-aminobutyric acid [ 19 ] levels in the brain.…”