Research Database
The only comprehensive database for clinical and medical research papers on the healthy benefits of matcha/green tea
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Cognitive Function
Matcha consumption leads to much higher intake of green tea phytochemicals compared to regular green tea. Previous research on caffeine, L-theanine, and epigallocatechin gallate (EGCG) repeatedly demonstrated benefits on cognitive performance.
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Heart Health
According to Harvard Medical School, “lowering your risk of cardiovascular disease may be as easy as drinking green tea. Studies suggest this light, aromatic tea may lower LDL cholesterol and triglycerides, which may be responsible for the tea's association with reduced risk of death from heart disease and stroke.”
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Mental Health
Matcha contains an amino acid called L-theanine, which has been shown to reduce physiological and psychological stresses. L-theanine also improves cognition and mood in a synergistic manner with caffeine, and promotes alpha wave production in the brain
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Cancer Prevention
Matcha/green tea has for many centuries been regarded as an essential part of good health in Japan and China. Many believe it can help reduce the risk of cancer, and a growing body of evidence backs this up.
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Immunity
A recent study in the journal Proceedings of the National Academy of Sciences concluded that drinking matcha daily greatly enhanced the overall response of the immune system. The exceedingly high levels of antioxidants in matcha mainly take the form of polyphenols, catechins, and flavonoids, each of which aids the body’s defense in its daily struggles against free radicals that come from the pollution in your air, water and foods.
Learn MoreMost Recent Research Articles
Author: Pouya Parsaei and Mehrdad Karimi and Sayyed Yazdan Asadi and Mahmoud Rafieian-kopaei
Background Adhesion formation is an important complication of abdomino-pelvic surgery. Green tea (Camellia sinensis) has anti-oxidant and anti-inflammatory effects which prevent production and accumulation of collagen and, thus, may reduce adhesion formation. The present study examined the effect of green tea alcoholic extract on intra-abdominal adhesion formation. Total phenolic, flavonoid and flavonol contents as well as anti-oxidant activity were also evaluated. Methods Thirty healthy male Wistar rats were randomly assigned to two equal groups of green tea (A) and distilled water (B). After anesthesia, the abdominal wall was opened and three shallow longitudinal and transverse incisions of 2 cm in length were made on the right side of the peritoneum by scalpel blade. A 2 × 2 cm square of the left abdominal wall peritoneum was removed by surgical scissors. Green tea extract or distilled water was introduced into the abdominal cavity of each rat. The rats were sacrificed two weeks post-laparotomy and adhesion bands were scored according to severity, extent and appearance. Fibrosis and inflammation were also scored via histopathological examination. Results There was a significant difference in mean adhesion scores between the green tea and distilled water groups (3.2 ± 3.503 and 7.33 ± 0.51, respectively) (p = 0.001). In terms of fibrosis (p = 0.002) and inflammation (p = 0.003) a statistically significant difference was also seen between the two groups following histopathological examination. Conclusion Green tea extract reduces intra-peritoneal adhesions in an animal model.
Author: Ramalingam Sundaram and Rajendran Naresh and Palanivelu Shanthi and Panchanatham Sachdanandam
The study was undertaken to evaluate the antidiabetic effect of green tea extract on carbohydrate metabolic key enzymes in control and streptozotocin high fat diet -induced diabetic rats. The daily oral treatment of green tea extract (300 mg/kg body weight) to diabetic rats for 30 days resulted in a significant reduction in the levels of plasma glucose, glycosylated hemoglobin (HbA1c) and increase in the levels of insulin and hemoglobin. The altered activities of the key enzymes of carbohydrate metabolism such as hexokinase, pyruvate kinase, lactate dehydrogenase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, glucose-6-phosphate dehydrogenase, glycogen synthase and glycogen phosphorylase in liver of diabetic rats were significantly reverted to near normal levels by the administration of green tea extract. Further, green tea extract administration to diabetic rats improved muscle and hepatic glycogen content suggesting the antihyperglycemic potential of green tea extract in diabetic rats. The obtained results were compared with metformin, a standard oral hypoglycemic drug. Thus, this study indicates that the administration of green tea extract to diabetic rats resulted in alterations in the metabolism of glucose with subsequent reduction in plasma glucose levels.
Author: Martina Bancirova
The antioxidant properties of the black and green tea are well known. The latent bloodstains are detectable by luminol. The bloodstains also can be cover up by drinks and foods containing the antioxidants; thus their presence can cause a decrease of the luminol light emission (false-negative results). The aim of this study was to quantify the light emission decrease of the chemiluminescent mixture prepared according to Weber (containing NaOH) and the chemiluminescent mixture of pH 7.4 (for the determination of the total antioxidant capacity) for the open air-dried sample. The black and green teas and white wine were used as the antioxidant's samples (high and low total antioxidant capacity). The significant decrease of the luminol chemiluminescent emission caused by the presence of the black and green teas (and comparable for both of them) was observed in comparison with the presence of white wine.
Author: Eugenia Gallo and Valentina Maggini and Margherita Berardi and Alessandra Pugi and Rosario Notaro and Giulia Talini and Giancarlo Vannozzi and Siro Bagnoli and Paolo Forte and Alessandro Mugelli and Vito Annese and Fabio Firenzuoli and Alfredo Vannacci
A case of autoimmune liver hepatitis is reported: the onset was triggered by consumption of green tea infusion in a patient taking oral contraceptives and irbesartan. We hypothesize that our patient, carrying genetic variant of hepatic metabolism making her particularly susceptible to oxidative stress, developed an abnormal response to a mild toxic insult, afforded by a combination of agents (oral contraceptives + irbesartan + green tea) that normally would not be able to cause damage. Her particular hepatic metabolism further increased the drugs’ concentration, favoring the haptenization of liver proteins, eventually leading to the development of an autoimmune hepatitis.
Author: Dominique Trudel and David P. Labbé and Monica Araya-Farias and Alain Doyen and Laurent Bazinet and Thierry Duchesne and Marie Plante and Jean Grégoire and Marie-Claude Renaud and Dimcho Bachvarov and Bernard Têtu and Isabelle Bairati
Objectives A two-stage, single-arm, phase II study was conducted to assess the effectiveness and safety of an epigallocatechin gallate (EGCG)-enriched tea drink, the double-brewed green tea (DBGT), as a maintenance treatment in women with advanced stage serous or endometrioid ovarian cancer (clinicaltrials.gov, NCT00721890). Methods Eligible women had FIGO stage III-IV serous or endometrioid ovarian cancer. They had to undergo complete response after debulking surgery followed by 6 to 8 cycles of platinum/taxane chemotherapy at the Centre Hospitalier Universitaire de Québec. They all had to drink the DBGT, 500 mL daily until recurrence or during a follow-up of 18 months. The primary endpoint was the absence of recurrence at 18 months. Statistical analyses were done according to the principle of intention to treat. Using a two-stage design, the first stage consisted of 16 enrolled patients. At the end of the follow-up, if 7 or fewer patients were free of recurrence, the trial stopped. Otherwise, accrual would continue to a total of 46 patients. Results During the first stage of the study, only 5 of the 16 women remained free of recurrence 18 months after complete response. Accordingly, the clinical trial was terminated. Women's adherence to DBGT was high (median daily intake during intervention, 98.1%, interquartile range: 89.7–100%), but 6 women discontinued the intervention before the end of their follow-up. No severe toxicity was reported. Conclusions DBGT supplementation does not appear to be a promising maintenance intervention in women with advanced stage ovarian cancer after standard treatment.
Author: Maksum Radji and Rafael Adi Agustama and Berna Elya and Conny Riana Tjampakasari
Objective To evaluate antibacterial activity of the Indonesian water soluble green tea extract, Camellia sinensis, against clinical isolates of methicillin–resistant Staphylococcus aureus (S. aureus) (MRSA) and multi-drug resistant Pseudomonas aeruginosa (MDR–P. aeruginosa). Methods Antimicrobial activity of green tea extract was determined by the disc diffusion method and the minimum inhibitory concentration (MIC) was determined by the twofold serial broth dilutions method. The tested bacteria using in this study were the standard strains and multi-drug resistant clinical isolates of S. aureus and P. aeruginosa, obtained from Laboratory of Clinical Microbiology, Faculty of Medicine, University of Indonesia. Results The results showed that the inhibition zone diameter of green tea extracts for S. aureus ATCC 25923 and MRSA were (18.970±0.287) mm, and (19.130±0.250) mm respectively. While the inhibition zone diameter for P. aeruginosa ATCC 27853 and MDR-P. aeruginosa were (17.550±0.393) mm and (17.670±0.398) mm respectively. The MIC of green tea extracts against S. aureus ATCC 25923 and MRSA were 400 μg/mL and 400 μg/mL, respectively, whereas the MIC for P. aeruginosa ATCC 27853 and MDR-P. aeruginosa were 800 μg/mL, and 800 μg/mL, respectively. Conclusions Camellia sinensis leaves extract could be useful in combating emerging drug-resistance caused by MRSA and P. aeruginosa.
Author: Jun Xi and Yujing Xue and Yinxiang Xu and Yuhong Shen
In this study, the ultrahigh pressure extraction of green tea polyphenols was modeled and optimized by a three-layer artificial neural network. A feed-forward neural network trained with an error back-propagation algorithm was used to evaluate the effects of pressure, liquid/solid ratio and ethanol concentration on the total phenolic content of green tea extracts. The neural network coupled with genetic algorithms was also used to optimize the conditions needed to obtain the highest yield of tea polyphenols. The obtained optimal architecture of artificial neural network model involved a feed-forward neural network with three input neurons, one hidden layer with eight neurons and one output layer including single neuron. The trained network gave the minimum value in the MSE of 0.03 and the maximum value in the R2 of 0.9571, which implied a good agreement between the predicted value and the actual value, and confirmed a good generalization of the network. Based on the combination of neural network and genetic algorithms, the optimum extraction conditions for the highest yield of green tea polyphenols were determined as follows: 498.8 MPa for pressure, 20.8 mL/g for liquid/solid ratio and 53.6% for ethanol concentration. The total phenolic content of the actual measurement under the optimum predicated extraction conditions was 582.4 ± 0.63 mg/g DW, which was well matched with the predicted value (597.2 mg/g DW). This suggests that the artificial neural network model described in this work is an efficient quantitative tool to predict the extraction efficiency of green tea polyphenols.
Author: Hui-Juan Zhang and Pan-Feng Gao and Xiao-Feng Guo and Hong Wang
In this study, an analytical method using 1,3,5,7-tetramethyl-8-(N-hydroxysuccinimidyl butyric ester)-difluoroboradiaza-s-indacene (TMBB-Su) as the labeling reagent has been developed to simultaneously detect Se-methylselenocysteine (SeMeCys), selenomethionine (SeMet), S-methylcysteine (SMeCys) and methionine (Met) in green tea and gynostemma pentaphyllum infusion by high performance liquid chromatography (HPLC) coupled to fluorescence detection. The derivatization of four targeted amino acids proceeded with 80 μmol/L TMBB-Su in 10 mmol/L mixed acid buffer (pH 7.20) at 25°C for 25 min, which was optimized by orthogonal array design. The baseline separation of these amino acid derivatives was obtained on a C8 column with a binary gradient elution using the mobile phase of 20 mmol/L mixed acid buffer solution (pH 6.40) and methanol with 2.5% tetrahydrofuran (THF). Under the optimal derivatization and separation conditions, the detection limit of each targeted amino acid was achieved to 0.2 nmol/L. A good linear relationship in the range of 0.001–1 μmol/L was obtained with a regression coefficient higher than 0.9912 for each targeted amino acids, and the relative standard deviations (RSDs) ranged from 1.8% to 3.5% for within-day determination (n = 6) and from 3.8% to 4.1% for between-day determination (n = 6). The proposed method can be used to detect selenium- and sulfur-containing amino acids simultaneously, compared to the existing HPLC with element-specific detection methods. Recoveries within 94.4–108.3% from tea and gynostemma pentaphyllum samples indicated that the matrix effect could be negligible in sample analysis. SeMeCys, SeMet, SMeCys and Met were all found in selenium enriched green tea and gynostemma pentaphyllum infusion. SeMeCys was also detected in normal green tea infusion with a mean content of 0.98 μg/g.
Author: Young-Kyung Kim and Laureen Jombart and Dominique Valentin and Kwang-Ok Kim
With the increasing demands of global trading, interests in cross-cultural comparisons have increased to gain understanding in the differences of sensory perception and consumer acceptability. The objective of this study was to compare the differences in perception by Korean and French consumers of green tea produced in Korea, China, and Japan, using Napping® followed by ultra flash profile. In addition, overall acceptability was examined in both countries. The results of Napping® showed that the Korean consumers were able to discriminate the green teas according to their origins and processing methods while the French consumers were less perceptive of these factors. The Korean consumers used more tea-related and roasting-related terms to describe the green teas. The sensory properties seemed to be the main factors in Napping® for the Korean consumers. On the other hand, the French consumers who were less familiar with green teas perceived the differences of green teas based on their acceptability. The result of this study indicated that familiarity affected the consumers' perception of green tea samples.
Author: Voravuth Somsak and Ubonwan Jaihan and Somdet Srichairatanakool and Chairat Uthaipibull
Impairment of renal function from oxidative stress during malaria infection is one of the leading causes of death in endemic areas. Since blood urea nitrogen and creatinine levels in plasma can be used as markers for monitoring renal damage, this study investigated the effect of green tea extract on reduction of blood urea nitrogen and creatinine levels during malaria infection using Plasmodium berghei ANKA infected mice as in vivo model. For in vivo testing, ICR mice were infected with 1 × 10 7 parasitized erythrocytes and green tea extract was subsequently administered orally twice a day for 10 consecutive days. Parasitemia was estimated by standard microscopy, and blood urea nitrogen and creatinine levels in plasma were also measured. It was found that parasitemia kept increasing until animal death, and is strongly correlated with high blood urea nitrogen and creatinine. The highest levels of blood urea nitrogen and creatinine in plasma were found on day 10 after infection. However, blood urea nitrogen and creatinine levels in plasma were reduced and decreased significantly (p < 0.01) in green tea extract treated mice, compared with untreated group. It can be concluded that green tea extract can protect and maintain renal function during malaria infection, and this extract can be developed for use as a supplement and combination therapy.