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: Sudathip Sae-tan and Kimberly A. Grove and Joshua D. Lambert
Green tea (Camellia sinensis, Theaceace) is the second most popular beverage in the world and has been extensively studied for its putative disease preventive effects. Green tea is characterized by the presence of a high concentrations of polyphenolic compounds known as catechins, with (−)-epigallocatechin-3-gallate (EGCG) being the most abundant and most well-studied. Metabolic syndrome (MetS) is a complex condition that is defined by the presence of elevated waist circumference, dysglycemia, elevated blood pressure, decrease serum high-density lipoprotein-associated cholesterol, and increased serum triglycerides. Studies in both in vitro and laboratory animal models have examined the preventive effects of green tea and EGCG against the symptoms of MetS. Overall, the results of these studies have been promising and demonstrate that green tea and EGCG have preventive effects in both genetic and dietary models of obesity, insulin resistance, hypertension, and hypercholesterolemia. Various mechanisms have been proposed based on these studies and include: modulation of dietary fat absorption and metabolism, increased glucose utilization, decreased de novo lipogenesis, enhanced vascular responsiveness, and antioxidative effects. In the present review, we discuss the current state of the science with regard to laboratory studies on green tea and MetS. We attempt to critically evaluate the available data and point out areas for future research. Although there is a considerable amount of data available, questions remain in terms of the primary mechanism(s) of action, the dose–response relationships involved, and the best way to translate the results to human intervention studies.
Author: Kanokwan Jumtee and Hajime Komura and Takeshi Bamba and Eiichiro Fukusaki
The sensory quality ranking of Japanese green tea (Sen-cha) was evaluated and predicted using volatile profiling and multivariate data analyses. The volatile constituents were extracted from tea infusion using vacuum hydrodistillation and analyzed using GC/MS. A quality of green tea could be discriminated to a high or low grade regarding the volatile profile by partial least squares discriminant analysis (PLS–DA). A quality ranking predictive model was developed from the relationship between subjective attributes (sensory quality ranking) and objective attributes (volatile profile) using partial least squares projections to latent structures together with the preprocessing filtering technique, orthogonal signal correction (OSC). Several volatile compounds highly contributed to model prediction were identified as various odor-active compounds, including geraniol, indole, linalool, cis-jasmone, dihydroactinidiolide, 6-chloroindole, methyl jasmonate, coumarin, trans-geranylacetone, linalool oxides, 5,6-epoxy-β-ionone, phytol, and phenylethyl alcohol. The whole fingerprints of these volatile compounds could be possible markers for the overall quality evaluation of green tea beverage.
Author: Raul Dominguez-Perles and Diego A. Moreno and Micaela Carvajal and Cristina Garcia-Viguera
Organic green tea, one of the most-consumed beverages worldwide, is rich in bioactive compounds (flavonols and flavanols) with healthy properties. Broccoli byproducts, consisting of leaves and stalks, are rich in bioactive compounds, including nitrogen–sulphur compounds (glucosinolates and isothiocyanates) and phenolics (chlorogenic and sinapic acid derivatives, and flavonoids), as well as essential nutrients (minerals and vitamins). They are of high interest as a source of health-promoting compounds, useful as ingredients for the development of functional foods. This work analyses minimally-processed broccoli byproducts as a source of bioactive ingredients to design novel beverages, using organic green tea as a food matrix. Green tea enriched with broccoli concentrates showed improved physical quality, phytochemical composition and antioxidant capacity. The functional quality of these novel beverages depends on the proportion of broccoli extracts added to the green tea. The results obtained in the present work should encourage the use of broccoli byproducts as ingredients in novel functional foods. Industrial relevance The industrial use of broccoli byproducts as an ingredient in the development of novel, functional foods may help to add value to the large amount of plant wastes generated in every cropping season, thus reducing their environmental impact. The objectives and aims of the EU producers, industry and stakeholders on the relationships between foods, nutrition and health, and therefore, the use of suitable ingredients from the agriculture to have impact on human health and the environment, with a sustainable use of natural resources are in agreement with this work, adding value to broccoli byproducts and encouraging the production of novel products and applications for nutritional and/or health claims under the EU Regulations (EC) No. 1924/2006 and 834/2007.
Author: Benno F. Zimmermann and Maike Gleichenhagen
Green tea seems to have a positive impact on health due to the therein-found flavanols. The amounts of these substances depend on tea preparation. In this paper, the influence of steeping time (3–7 min) and temperature (70–100 °C) on the content of the main flavanols in green tea (epicatechin EC, epicatechin gallate ECg, epigallocatechin EGC, and epigallocatechin gallate EGCg) is presented. Furthermore, additives (phosphate buffers, ascorbic acid in different amounts, and citric acid) are used to investigate the influence of pH, antioxidative, and chelating agents, simulating the addition of lemon juice or pure vitamin C. The concentrations of flavanols in tea without additives are highest after 7 min of steeping at a constant 100 °C; the respective lowest and highest concentrations of the flavanols differ widely: 2.1-, 2.2-, 3.1-, and 3.6-fold for EC, EGC, EGCg, and ECg, respectively. The additives increase the flavanol concentrations up to 20%. pH emerges as the decisive factor for increasing concentrations, rather than the chemistry of the used additive.
Author: Youngmok Kim and Kevin L. Goodner and Jong-Dae Park and Jeong Choi and Stephen T. Talcott
Monomeric flavonoids (flavan 3-ols or tea catechins) present in Camellia sinensis leaf are transformed to polymeric theaflavin and thearubigin by oxidation occurring during tea fermentation. The distinctive colour, decreased bitterness and astringency, and characteristic flavour are derived from the fermentation process giving fermented teas a marked distinction from non-fermented green tea. Even though teas are available in many different fermentation levels from green to black, the difference in phytochemicals and volatile compounds in teas with different degrees of fermentation has not been fully investigated yet within the same tea leaf. The objective of this study was to observe non-volatile phytochemicals including polyphenolic and volatile compounds changes by oxidation under strict processing control and to evaluate the degree of fermentation for the maximum antioxidant capacity with the same tea material. Harvested tea leaf was immediately processed to different degrees of oxidative fermentation (0%, 20%, 40%, 60%, and 80%). Tea infusions brewed with each processed tea leaf were analysed for polyphenolic profile, total soluble phenolics, antioxidant capacity, and volatile profile using LC–MS, HPLC, Folin–Ciocalteu assay, Oxygen Radical Absorbance Capacity (ORAC), and GC–MS analyses. The flavonoids in non-fermented green tea were significantly lessened during the oxidative fermentation process and the decreased monomeric flavonoids were transformed to polymeric theaflavin and thearubigin as the leaves were more processed. Total soluble phenolics and antioxidant capacity were significantly higher as tea leaves were less processed with a high correlation with individual polyphenolic changes. Volatile compounds present in tea leaf were analysed by GC–MS to observe changes due to processing and were utilised to create a model to differentiate fermentation based on volatile composition. Twenty-four compounds were used to build an initial model which was optimised to 16 compounds with complete separation of the groups using discriminant function analysis. The data suggested that fermentation diminished antioxidant capacity of tea and could result in lowering potential health benefits from flavonoids. This result should be considered for tea manufacturing and the development of functional foods desiring maximum potential health benefits from antioxidant flavonoids in tea.
Author: Santosh K. Katiyar
Excessive exposure of the skin to solar ultraviolet (UV) radiation is one of the major factors for the development of skin cancers, including non-melanoma. For the last several centuries the consumption of dietary phytochemicals has been linked to numerous health benefits including the photoprotection of the skin. Green tea has been consumed as a popular beverage world-wide and skin photoprotection by green tea polyphenols (GTPs) has been widely investigated. In this article, we have discussed the recent investigations and mechanistic studies which define the potential efficacy of GTPs on the prevention of non-melanoma skin cancer. UV-induced DNA damage, particularly the formation of cyclobutane pyrimidine dimers, has been implicated in immunosuppression and initiation of skin cancer. Topical application or oral administration of green tea through drinking water of mice prevents UVB-induced skin tumor development, and this prevention is mediated, at least in part, through rapid repair of DNA. The DNA repair by GTPs is mediated through the induction of interleukin (IL)-12 which has been shown to have DNA repair ability. The new mechanistic investigations support and explain the anti-photocarcinogenic activity, in particular anti-non-melanoma skin cancer, of green tea and explain the benefits of green tea for human health.
Author: A.V.S. Perumalla and Navam. S. Hettiarachchy
Using “natural green” plant extracts or their derived products in various food and beverage applications is an increasing trend in the food industry. Selection of these plant extracts and their application depends on their functional properties, availability, cost effectiveness, consumer awareness and their effect on the sensory attributes of the final product. Green tea extract (GTE) and grape seed extract (GSE) are two popular plant extracts that have been widely used in various food and beverage applications. Green tea is a widely consumed beverage that has attracted more attention in the recent years due to its health benefits like antioxidant, antimicrobial, anticarcinogenic and anti-inflammatory properties. Grape seed extract is derived from the grape seeds that is extracted, dried and purified to produce polyphenolic compounds-rich extract that also has well documented antioxidant, antimicrobial and anti-inflammatory properties. These two plant extracts (polyphenolic and proanthocyanidin rich compounds) have potential antioxidant properties by inhibiting the lipid oxidation and warmed over flavors and antimicrobial activities against major food borne pathogens like Listeria monocytogenes, Salmonella Typhimurium, Escherichia coli O157:H7, and Campylobacter jejuni in preventing pathogen contamination. Furthermore, they have demonstrated synergism in antimicrobial activity when used in combination with organic acids (malic, tartaric acid, benzoic acids etc.), bacteriocins like nisin or chelating agents like EDTA in various model systems including fresh produce (fruits and vegetables), raw and ready-to-eat meat and poultry products. Apart from beneficial effects of grape seed extract in food safety and quality, concerns regarding the side effects of GSE are also addressed. Nevertheless, persistent recalls of the food products involving foodborne pathogens despite various control measures calls for efficient bacteriostatic and bactericidal agents and technologies to deliver the active components for an effective inhibition of pathogens. Therefore, further research involving electrostatic spray and nanoscale delivery of the active components present in these natural, green, plant extracts and using them as a component in multiple hurdle approach would enhance the food safety and quality in addition to providing alternative “green” solutions to the food processors.
Author: Joanna Bajerska and Małgorzata Wozniewicz and Jan Jeszka and Slawomira Drzymala-Czyz and Jaroslaw Walkowiak
Green tea is associated with beneficial health effects mainly because of its body fat–reducing and hypocholesterolemic activities, but an effective dose without pronounced influence on protein availability is unknown. The objective of this study was to examine the hypothesis that green tea aqueous extract (GTAE) depending on dose improves cardiovascular risk indicators such as body weight, visceral fat content, and atherogenic index of plasma and does not have unfavorable effect on protein availability in rats fed with a high-fat diet. The rats fed with a high-fat diet enriched with 1.1 and 2.0% GTAE for 8 weeks had significantly (P < .05) lower atherogenic index (in both groups, about 14.3%). Only administration of 2.0% GTAE significantly (P < .05) decreased body weight gain (5.6%) and prevented visceral fat accumulation (17.8%) in rats. However, considerably (P < .05), reduction in the digestion of protein (but not fat) was observed in both GTAE groups (1.1% GTAE: 82.6% ± 1.8%; 2.0% GTAE: 84.3% ± 0.8%) when compared to the control (93.3% ± 1.5%). It was concluded that GTAE may have preventive effects on the accumulation of visceral fat but only in higher doses. Although both doses improved cardiovascular risk indicators, they, in addition, significantly inhibited protein digestion.
Author: D.W. Jun and E.K. Kim and H.S. Choi and Y.I. Kown and W. Sohn and O.W. Kwon and K.N. Lee and H.L. Lee and O.Y. Lee and B.C. Yoon and T.Y. Kim and J.H. Sohn
Background: There are several epidemiologic studies that coffee and tea consumption could lower serum liver enzyme activity, and inhibit the progression of liver disease in high-risk subjects. However, many conflicting results have been also reported according to type of coffee and whether the use of filters. Most studies were base on specific cohort group and there are few general population base studies. This study examined on population based study whether coffee has a protective effect when consumed in moderate quantities in metabolic syndrome and liver inflammation. Methods: We used cross-sectional data on coffee, tea consumption frequency, and metabolic parameters of 5,283 adults, aged 20 years and older, who participated in the third Korea National Health and Nutrition Examination Survey (KNHANES). We examined the relationship between coffee, tea, and caffeine intake and metabolic parameters using linear regression. Additionally, we examined the relationship with liver enzyme activity using logistic regression. Intake was assessed by a food frequency questionnaire. Result: In our study, more than 90% subjects intake instant coffee mix (mix with confectioners’ sugar, powdered creamer, and soluble coffee). Total calorie intake and body mass index were higher in individuals with coffee intake >2 cups daily compared with those with no coffee use (p < 0.001 vs. p = 0.021, respectively). However, a gradual increase in the frequency of coffee consumption was associated with stepwise decrease in prevalence of hypertension, dyslipidemia, and abnormal fating glucose, which was independent of total calorie, and BMI. The prevalence of metabolic syndrome was strikingly decreased from 48.8%, 46.5%, to 40.9% according to the quartile of coffee consumption (p = 0.01, p for trend <0.001). After adjusting for other covariates, the differences remained significant. But frequency of coffee consumption did not affect the liver enzyme activity on general population and high risk group. In cases of normal BMI subjects (23–25 kg/m2), coffee intake had a tendency to increased liver enzyme activity. Frequency of green tea intake did not showed protective effects on liver and metabolic aspects. Conclusion: In this large, national, population-based study, consumption of coffee was associated with lower the risk of metabolic syndrome.
Author: A.V. Kristen and S. Lehrke and D. Mereles and P.A. Schnabel and C. Röcken and P. Ehlermann and T.J. Dengler and K. Altland and H.A. Katus
Purpose: Cardiac involvement is common in both forms of transthyretin (TTR) amyloidosis, variant and non-variant (senile) form. As no medical treatment is available yet liver transplantation is the only accepted treatment for patients with variant TTR amyloidosis and mild cardiac invovlement, but not for patients with senile amyloidosis. In patient with advanced cardiac amyloidosis heart transplantation is the only available treatment option. In 2007, a patient having ALA amyloidosis described a decrease of his LV wall after daily consumption of 2 1 of green tea (Hunstein, Blood 2007 110:2216). This prospective, open-label, single center interventional trial was performed to confirm the observation in patients with amyloid TTR cardiomyopathy. Methods and Materials: 19 patients with cardiac TTR amyloidosis were evaluated by standard blood tests, echocardiography, and cardiac MRI (n=9) while consuming green tea and/or green tea extract for 12 months. 5 patients were not followed-up for reasons of death (n=2), poor health (n=2), and heart transplantation (n=1). Results: After consumption of green tea and/or green tea extract for 12 months a significant average decline of LV myocardial mass was observed by echo (-15%) and MRI (-10%) accompanied by an increase of mitral annular systolic velocity (9%). In 11 of 14 (79%) patients we observed a reduction of cardiac mass by acho and by MRI in 9/9 (100%) suggesting a loss of cardiac amyloid. In all 14 patients total cholesterol (191.9 ± 8.9 mg/dL vs. 172.7 ± 9.4 mg/dL; p<0.01) and LDL cholesterol (105.8 ± 7.6 mg/dL vs 89.5 ± 8.0 mg/dL; p<0.01) decreased significantly during the observational period. NT-proBNP plasma levels remained unchanged. No serious adverse side-effects were reported by any of the participants. Conclusions: Consumption of green tea and green tea extracts appear to represent a promising therapeutic tool to halt the progression of the amyloid apposition and even decreases the cardiac amyloid load in patients with TTR amyloidosis. Thus, it is a promising treatment approach that might prevent heart transplantation.