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.
Learn MoreHeart 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.”
Learn MoreMental 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
Learn MoreCancer 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.
Learn MoreImmunity
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: C. Samaniego-Sánchez and Y. Inurreta-Salinas and J.J. Quesada-Granados and R. Blanca-Herrera and M. Villalón-Mir and H. López-García de la Serrana and M.C. López Martínez
This paper presents an investigation into the influence of several culinary factors, such as water temperature, infusion time, stirring and dosage form, on polyphenol content and antioxidant capacity (TEAC values) during the domestic preparation of green tea. The results obtained show that water temperature and infusion time strongly influence total polyphenol levels and the antioxidant capacity of green tea. Temperatures of 70–80 °C together with infusion times of 3–5 min produced greatest effect, in this respect. At 90 °C, extraction was faster and more effective. However, prolonged infusion at this temperature may cause a loss of polyphenol compounds and, consequently, of antioxidant capacity. Factors such as agitation and dosage form do not seem to have much influence. Furthermore, it was found that pure green tea infusions have higher antioxidant properties than do blends of green tea with aromatic herbs and fruits.
Author: S. Ellinger and N. Müller and P. Stehle and G. Ulrich-Merzenich
Purpose Epidemiological data suggest that green tea (GT) consumption may protect against cardiovascular diseases (CVDs) and different types of cancer. This effect is attributed primarily to the antioxidant properties of flavanols from GT. This review provides an overview of controlled intervention studies investigating the effect of GT consumption on antioxidant effects ex vivo and in vivo. Methods The Medline and Cochrane databases were searched independently by two investigators for controlled intervention studies (English) on GT consumption and antioxidant effects published up to June 2010. Thirty-one studies investigating antioxidant effects ex vivo [plasma antioxidant capacity (AC), DNA's resistance against oxidative induced damage) or in vivo (lipid and protein oxidation, DNA damage] met the criteria. Results were compared by considering the participants, the dose of GT, the amount of ingested flavanols, the duration of supplementation and the investigated biomarkers. Results The comparison between the studies was difficult as relevant data, e.g., on flavanol concentration in plasma (10 of 31 studies) or on major antioxidants contributing to AC, were often missing. Lipid peroxidation and DNA damage were commonly investigated. Data on protein oxidation are scarce. An antioxidant effect of at least one parameter (increase in AC or reduction of oxidative stress marker) was observed in 15 out of 22 studies by daily consumption of GT, primarily in participants exposed to oxidative stress (smokers or mixed collectives of smokers and non-smokers and physical activity) and in 6 out of 9 studies investigating the bolus consumption of GT. Conclusion There is limited evidence that regular consumption of GT in amounts of at least 0.6–1.5 l/day may increase AC and reduce lipid peroxidation (especially oxidation of LDL). This may contribute to the protection against CVDs and different types of cancer. Beneficial effects seem to be more likely in participants exposed to oxidative challenge.
Author: Forouzanfar Ali and Orafai Hossein and Maroofian Ahmad and Golestani Shayan
Introduction: Recently great interest has been focused on the biological properties of green tea catechins because of their health benefits such as anti-inflamatory, anti-oxigenicity, anti-mutagenicity, anti-tumorgenicity and anti-carcinogenicity. These catechins are polyphenolic compounds belonging to the flavonoid family, which are present in relatively high concentration in green tea leaves (Camellia sinensis) and, at lower levels, in grape seeds and Cistus species. The aim of this study is to introduce catechin molecules structure and their potential therapeutic properties on various diseases. Materials and methods: The catechins are composed of a family of four major substances, epicatechin (EC), epicatechin gallate (Ecg), epigallocatechin (EGC), and epigallocatechin gallate (EGCg) and four minor catechins, catechin©, catechin gallate (Cg), galloca- techin (GC) and gallocatechin gallate (GCg) as epimers of the major catechins. Organic solvents such as methanol and acetonitrile or hot water have been used as solvents to extract catechins from tea leaves. Results: Green tea catechins consumption have been linked to a lower incidence of various pathologies, including cancer, cardiovascular disease and hypertension, diabetes, obesity, allergy, asthma, arthritis, immune system disorders, oral and periodontal diseases, osteoporo- sis, bacterial and viral infections and dermatological lesions. Recently we have shown that green tea catechins have improved periodontal status of patients with gingivitis suffering from gum inflammation and bleeding. Conclusion: Based on the findings of this review green tea catechins can be extracted by various methods and used in different pharmaceutical forms. Several studies have shown that green tea catechins can be applied for preventing and treating numerous diseases.
Author: Dulce M.A. Gil and Pedro L.V. Falé and Maria L.M. Serralheiro and Maria J.F. Rebelo
An amperometric biosensor containing immobilised laccase from Trametes versicolor was used for the quantification of phenolic compounds in herbal infusions and green tea samples, from nine botanical families. The main purpose of this research was to correlate the bioelectrochemical polyphenolic index (BPI) of the samples with the total phenolic content according to the Folin–Ciocalteu spectrophotometric method (TPC), and the total antioxidant activity (TAA) measured by TEAC (Trolox Equivalent Antioxidant Capacity). A strong correlation between BPI, TPC, and TAA was obtained for 10 herbal infusion samples. However, when a green tea sample was taken into account, a decrease in the linear correlation coefficient (r2) from 0.9949 to 0.2599 and 0.5609 to 0.1086 for the relationship between BPI/TPC and BPI/TAA, respectively, was observed. Thus, we could conclude that the green tea’s matrix affects the laccase-based biosensor response. HPLC–DAD analysis showed the presence of gallic acid only in the green tea sample. The results have indicated that gallic acid inhibited the laccase activity regarding the ABTS oxidation in a concentration-dependent manner. The very strong correlation between BPI/TPC obtained for herbal infusions allow us to conclude that the laccase-based biosensor, used in this research, provides a valuable tool to obtain a valid estimation of the classical Folin–Ciocalteu index, in an uncomplicated and fast way.
Author: Jun Xi and Deji Shen and Ye Li and Rui Zhang
In this study, the effect of ultrahigh pressure extraction at pressures of 150 MPa, 250 MPa, 350 MPa and 450 MPa on the total phenolic contents, the extraction yields and the antioxidant activities of green tea were investigated. The antioxidant activities of these extracts were analyzed using DPPH radical scavenging activity and total antioxidant capacity. The results showed that the phenolic contents and the antioxidant activities of extracts were greatly influenced by high pressure. The total phenolic contents and the antioxidant activities of ultrahigh pressure extraction at 450 MPa were higher than those of other ultrahigh pressure extraction and conventional extraction. The high content of phenolic compounds in the green tea leaves could account for the antioxidant activity. This study indicated that this new technology can benefit the food and pharmaceutical industries.
Author: Takayuki Maruyama and Takaaki Tomofuji and Yasumasa Endo and Koichiro Irie and Tetsuji Azuma and Daisuke Ekuni and Naofumi Tamaki and Tatsuo Yamamoto and Manabu Morita
Objective This study examined the effects of a dentifrice containing green tea catechins on gingival oxidative stress and periodontal inflammation using a rat model. Design Twenty-four male Wister rats were randomly divided into four groups. The first group (Control group) received no treatment for 8 weeks. Periodontal inflammation was induced in the second group for 8 weeks. Periodontal inflammation was induced in the last two groups for 8 weeks and dentifrices with or without green tea catechins were topically applied to the gingival sulcus daily for 4 weeks prior to the end of the experimental period. Results Rats that had experimental periodontal inflammation showed apical migration of the junctional epithelium, alveolar bone loss and inflammatory cell infiltration in the connective tissue subjacent to the junctional epithelium at 8 weeks, whilst the control group showed no pathologic changes. Topical application of a green tea catechin-containing dentifrice reduced inflammatory cell infiltration in the periodontal lesions to a greater degree than the control dentifrice at 8 weeks. The gingiva in which green tea catechin-containing dentifrice was applied also showed a lower level of expression of hexanoyl-lysine (a marker of lipid peroxidation), nitrotyrosine (a marker of oxidative protein damage), and tumour necrosis factor-α (an indicator of pro-inflammatory cytokines) at 8 weeks compared to gingiva in which the control dentifrice was applied. Conclusions Adding green tea catechins to a dentifrice may contribute to prevention of periodontal inflammation by decreasing gingival oxidative stress and expression of pro-inflammatory cytokines.
Author: Jean-Pierre Ele-Ekouna and Corinne Pau-Roblot and Bernard Courtois and Josiane Courtois
From green tea leaves, two distinct pectin fractions were obtained based on their solubility in water. Polyphenols were detected only in the easily water soluble fraction (P1). The estimated uronic acids/neutral sugars ratio was 1.7 in the easily water soluble pectin fraction (P1), and 1.0 in the less water soluble fraction (P2). Homogalacturonan sequences (HGAs) corresponded to about 62% of the P1 pectin fraction but only 47% of the P2 fraction. After degradation of the two pectin fractions by pectin lyase, chemical studies revealed rhamnogalacturonan RG I and RG II regions present in the P1 pectin fraction, whereas only RG I sequences were detected in the P2 pectin fraction. The degree of substitution was lower for HGAs of the P1 pectin fraction than P2. Different acetylation patterns for the two fractions were observed. Polyphenols extracted simultaneously with pectins were present only in HGA fractions from P1.
Author: Saad M. Bin Dajem and Ali A. Shati and Mohamed A. Adly and Osama M. Ahmed and Essam H. Ibrahim and Osama M.S. Mostafa
This study was designed to assess the effect of green tea, an aqueous extract of Camellia sinensis, on the oxidative stress, antioxidant defense system and liver pathology of Schistosoma mansoni-infected mice. Green tea at concentration of 3% (w/v) was given orally to treated mice as sole source of drinking water from the end of the 4th week to the end of 10th week post-infection; untreated mice were allowed to drink normal water. The data of the studied S. mansoni-infected mice exhibited a suppression of hepatic total antioxidant capacity, superoxide dismutase (SOD), catalase (CAT) activity and glutathione content. The liver lipid peroxidation was deleteriously elevated in S. mansoni-infected mice. The hepatic total protein content, AST and ALT activities were profoundly decreased in the S. mansoni-infected mice. Most hepatocytes were damaged and showed abnormal microscopic appearance with aggressive necrosis. Both total protein and glycogen levels have been greatly reduced as indicated by histochemical examination. The treatment of S. mansoni-infected mice with green tea succeeded to suppress oxidative stress by decreasing the lipid peroxides but failed to significantly enhance the antioxidant defense system and deteriorated changes owing to liver damage and necrosis. In consistence with biochemical data, histopathological and histochemical data indicated that treatment of S. mansoni-infected mice with green tea could ameliorate hepatocytes thus reduce cellular necrosis and partially restore both total protein and glycogen levels. Thus, the study concluded that the green tea suppresses the oxidative stress through its constituent with free radicals scavenging properties rather than through the endogenous antioxidant defense system.
Author: Yanli Li and Shen-Chih Chang and Binh Y. Goldstein and William L. Scheider and Lin Cai and Nai-Chieh Y. You and Heather P. Tarleton and Baoguo Ding and Jinkou Zhao and Ming Wu and Qingwu Jiang and Shunzhang Yu and Jianyu Rao and Qing-Yi Lu and Zuo-Feng Zhang and Lina Mu
Objective: Green tea has been found to possess anti-inflammatory, anti-oxidative and anti-carcinogenic properties. The present study examines the association between green tea drinking and hepatocellular carcinoma (HCC) and its interactions with other risk or protective factors and single nucleotide polymorphisms (SNP) of inflammation and oxidative stress related genes. Methods: A population-based case-control study with 204 primary HCC cases and 415 healthy controls was conducted in Taixing, China. Epidemiological data were collected using a standard questionnaire. SNPs of genes of the inflammation and metabolic pathways were genotyped at the UCLA Molecular Epidemiology Laboratory. Logistic regression was performed to estimate adjusted odds ratios and 95% confidence intervals. Results: Longer duration and larger quantities of green tea consumption were inversely associated with primary HCC. Individuals who drank green tea longer than 30 years were at lowest risk (adjusted OR = 0.44, 95% CI: 0.19–0.96) compared with non-drinkers. A strong interaction was observed between green tea drinking and alcohol consumption (adjusted OR for interaction = 3.40, 95% CI: 1.26–9.16). Green tea drinking was also observed to have a potential effect modification on HBV/HCV infection, smoking and polymorphisms of inflammation related cytokines, especially for IL-10. Conclusion: Green tea consumption may protect against development of primary HCC. Potential effect modifications of green tea on associations between primary HCC and alcohol drinking, HBV/HCV infection, and inflammation-related SNPs were suggested.
Author: Tia M. Rains and Sanjiv Agarwal and Kevin C. Maki
Green tea catechins (GTC) are polyphenolic compounds present in the unfermented dried leaves of the plant, Camellia sinensis. Results from a number of randomized, controlled intervention trials have shown that consumption of GTC (270 mg to 1200 mg/day) may reduce body weight and fat. There are several proposed mechanisms whereby GTC may influence body weight and composition. The predominating hypothesis is that GTC influences sympathetic nervous system (SNS) activity, increasing energy expenditure and promoting the oxidation of fat. Caffeine, naturally present in green tea, also influences SNS activity, and may act synergistically with GTC to increase energy expenditure and fat oxidation. Other potential mechanisms include modifications in appetite, up-regulation of enzymes involved in hepatic fat oxidation, and decreased nutrient absorption. This article reviews the evidence for each of these purported mechanisms, with particular reference to studies in humans.