Research Database
The only comprehensive database for clinical and medical research papers on the healthy benefits of matcha/green tea
Explore Research Topic
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 More
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.”
Learn More
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
Learn More
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.
Learn More
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: Man Li and Jia-Hui Zhang and Ke-Xue Zhu and Wei Peng and Shi-Kang Zhang and Bin Wang and Yue-Jin Zhu and Hui-Ming Zhou
Superfine green tea powder (SGTP) was used to substitute 0 g, 1 g, 2 g, and 3 g of 100 g wheat flour (defined as 0SGTP, 1SGTP, 2SGTP and 3SGTP respectively) to make fresh noodles. The effects of SGTP on the viscosity, thermodynamic and rheological properties of wheat flour were evaluated, as well as the sheet colour, cooking quality, texture properties and sensory characteristics of green tea noodles. The results revealed that the stability, elastic modulus (G′) and viscous modulus (G″) of wheat dough all increased with the increase of green tea powder proportion. No significant differences were found in gelatinisation properties of the green tea-flour systems. Furthermore, adding SGTP could significantly (P < 0.05) retard the retrogradation of the gelatinised wheat flour gel. L∗ value of fresh noodles decreased as SGTP content increased while |a∗| value firstly increased and then decreased at 3 g/100 g. The 2SGTP noodle samples showed the least cooking loss. Sensory evaluation indicated that the control and the 2SGTP fresh noodles scored significantly (P < 0.05) higher in terms of colour. No significant difference was detected for the mouthfeel and overall acceptability among all samples.
Author: Hyong Seok Park and Nam Gyu Im and Kyoung Heon Kim
The decaffeination of green tea using supercritical carbon dioxide (SC-CO2) was optimized by response surface methodology (RSM) for the maximal removal of caffeine, and the coextration of chlorophylls was also monitored during decaffeination. The experimental conditions for the SC-CO2 extraction of caffeine were set up according to the Box-Behnken design of RSM. The relationships between the extraction yield of caffeine and various parameters used for the SC-CO2 extraction such as pressure, temperature and concentration of ethanol were studied at a fixed CO2 flow rate. The extraction yields of caffeine and total chlorophyll were significantly influenced by extraction pressure, temperature and concentration of cosolvent, and their extraction yields behaved almost in parallel at different extraction conditions that were obtained by varying pressure, temperature and ethanol cosolvent concentration. At the optimal decaffeination conditions such as 3.0 g of 95% (v/v) ethanol cosolvent per 100 g of CO2, 23 MPa, 63 °C and an extraction duration of 120 min for 10 g of green tea leaves, the extraction yields for caffeine and catechins were 96.60% (w/w) and 40.61% (w/w), respectively, and the substantial coextraction of total chlorophyll (43.09% of the total amount) was also observed during the decaffeination process.
Author: Jing Wang and Wei Zhang and Lu Sun and Herbert Yu and Quan-Xing Ni and Harvey A. Risch and Yu-Tang Gao
Background: Little is known about the etiology of pancreatic cancer. Epidemiological studies on tea consumption and pancreatic cancer risk have been inconclusive. The purpose of the present study was to investigate the association between green tea drinking and the risk of pancreatic cancer in urban Shanghai, China. Methods: In this population-based case–control study conducted in urban Shanghai, 908 cases of pancreatic cancer and 1067 healthy controls were recruited. Information on tea drinking, including type of tea, amount of tea consumption, temperature of tea, and the duration of regular tea drinking, were collected via interview questionnaire. Results: We examined the association of multiple tea drinking habits with the risk of pancreatic cancer. In women, regular green tea drinking was associated with 32% reduction of pancreatic cancer risk (OR 0.68, 95% CI 0.48–0.96), compared to those who did not drink tea regularly. Increased consumption and longer duration of tea drinking were both associated with reduced pancreatic cancer risk in women. Among regular tea drinkers, lower temperature of tea was associated with reduced risk of pancreatic cancer in both men and women, independent of amount or duration of tea drinking. Conclusions: Habits of green tea drinking, including regular drinking, amount of consumption, persistence of the habit, and tea temperature, may lower pancreatic cancer risk.
Author: Li Wang and Li-Hong Gong and Chang-Jian Chen and Han-Bing Han and Hai-Hang Li
A highly efficient column-chromatographic extraction (CCE) followed by sequential adsorption to extract and separate bioactive compounds from green tea was developed. Tea powder was loaded into columns with 4-fold solvents and eluted through a cyclic CCE. High-quality tea extracts with greater than 90% extraction efficiencies of polyphenols, epigallocatechin-3-gallate, caffeine, theanine and polysaccharides were obtained with 4-fold water circulated five times among different columns at 70 °C. Similar results, except for low polysaccharide extraction (35.5%), were obtained with 4-fold 30% ethanol circulated three times at room temperature. The highly concentrated water extraction was directly passed through columns of polyamide, DM130 macroporous and 732 ion exchange resins, resulting in high-purity polyphenols (99%), caffeine (98%) and theanine (98%) after simple purification of the eluates from each column. This method uses simple equipment, minimum solvents and can be used for both quantitative analysis and continuous preparation of high-quality tea extracts and bioactive compounds.
Author: Jie Yin and Eleonora Miquel Becker and Mogens L. Andersen and Leif H. Skibsted
The antioxidant effects of α-tocopherol (TOH) in combination with green tea extract (GTE), the green tea polyphenol (−)-epicatechin (EC) or the isomeric (+)-catechin (C), were investigated using different lipid systems based on high linoleic sunflower oil: bulk oil, o/w-emulsion and a phosphatidylcholine-based liposome system. Both polyphenols as well as TOH were efficient antioxidants in all systems when used alone, as detected by the formation of free radicals and conjugated dienes and by oxygen consumption. Strong synergistic effect was found for the combination of TOH and GTE in a methyl linoleate o/w-emulsion and in the pure bulk oil, while only an additive effect was observed in a liposome system. The synergism was already evident for the tendency for radical formation in the bulk oil as detected by electron spin resonance (ESR) spectroscopy. On the contrary, combinations of TOH with either EC or C showed clear synergistic effects in both heterogeneous systems, but antagonistic or additive effects in bulk oil. GTE may accordingly be used to protect both vegetable oils and their emulsions against oxidation through enhancement of the activity of their endogenous antioxidants, while GTE is less efficient in the protection of phospholipids as in liposomes.
Author: Quan V. Vuong and John B. Golding and Minh H. Nguyen and Paul D. Roach
Only the apical bud and the top four leaves are normally used to make high quality green teas, while the older lower leaves are cut and used for mulch. The aim was to determine whether the old fifth to tenth leaves could be used to make caffeinated and decaffeinated green tea catechin powders. The leaves were decaffeinated by blanching in water at 100 °C for 10 min to remove 80% of the caffeine while retaining 85% of the catechins. The leaves were then extracted in water at 80 °C and freeze drying gave 100% yields of extractable powder and catechins while spray drying gave 20–25% lower yields. Decaffeination and spray drying also increased the conversion of epistructured to non-epistructured catechins. Therefore, this study has shown that old green tea leaves, which are usually discarded, could be used as an underutilised source to make caffeinated and decaffeinated green tea catechin powders.
Author: M.A. Islam and M. Ebihara
The determination of mineral compositions of Japanese green tea leaves was carried out using a combination of PGA (neutron-induced prompt gamma-ray analysis) and INAA (instrumental neutron activation analysis). Due to the nondestructive, multi-element analytical capability and minimal sample preparation, these techniques can easily be used to determine a wide range of elemental contents (from 7.4% of H to 7.1 ng/g of Sc) in tea leaves. The extraction efficiencies of the elements in tea infusion were evaluated by comparing average elemental concentrations of the tea leaves before and after infusion, which show that Cl (93%), Br (80%), K (71%), Rb (66%), Cs (60%), Na (59%) and Co (51%) are highly extracted, whereas Fe (9%), La (7%) and Mn (5%) are poorly extracted by a 6 min hot water infusion process. Although K has a high content in green tea leaves with high extraction efficiency, as much as seven cups (250 mL each cup) of green tea infusion need to be consumed to get a source of 10% daily value of this mineral.
Author: Raúl Domínguez-Perles and Diego A. Moreno and Cristina García-Viguera
Broccoli has risen as rich in bioactive phytochemicals (glucosinolates and phenolic compounds) closely linked with the reduction of cancer risk. Green tea infusion is a beverage that also contains anticarcinogenic compounds, mainly represented by flavanols. The compounds present in new broccoli-enriched green tea drinks and their potential antitumoral activity in vitro were evaluated. The distinct compounds present in the prepared beverages were identified by HPLC–PAD–ESI-MSn and quantified by HPLC–PAD. Caco-2 and CCD-18Co cell lines were exposed to growing percentages (0.2–5%) of infusions of distinct combinations of plant material. The time-dependent cytotoxicity on the malignant cells was also achieved. Cell death was evaluated by trypan blue dye exclusion and a more efficient specific cytotoxic effect on Caco-2 cells was observed on the cells incubated with the mixture of broccoli and green tea than on cells exposed to control infusions. Broccoli added to green tea resulted in a combination of phytochemicals with antitumoral activity with potential for further developments in mechanistic models and the design of novel foods.
Author: M.S. El-Shahawi and A. Hamza and S.O. Bahaffi and A.A. Al-Sibaai and T.N. Abduljabbar
Green tea seems to have a positive impact on health due to the catechins-found as flavanols. Thus, the present study was aimed to develop a low cost reversed phase high performance liquid chromatographic (HPLC) method for simultaneous determination of flavanol contents, namely catechin (C), epicatechin (EC), epigallocatechin (EGC), epicatechin 3-gallate (ECG) and epigallocatechin 3-gallate (EGCG) and caffeine in 29 commercial green tea samples available in a Saudi Arabian local market. A C-18 reversed-phase column, acetonitrile–trifluoroacetic acid as a mobile phase, coupled with UV detector at 205 nm, was successfully used for precise analysis of the tested analytes in boiled water of digested tea leaves. The average values of N (No. of theoretical plates), HETP (height equivalent of theoretical plates) and Rs (separation factor) (at 10 μg ml−1of the catechins EC, EGC, EGCG and ECG) were 2.6 × 103 ± 1.2 × 103, 1.7 × 10−3 ± 4.7 × 10−4 cm and 1.7 ± 5.53 × 10−2, respectively. The developed HPLC method demonstrated excellent performance, with low limits of detection (LOD) and quantification (LOQ) of the tested catechins of 0.004–0.05 μg ml−1and 0.01–0.17 μg ml−1, respectively, and recovery percentages of 96–101%. The influence of infusion time (5–30 min) and temperature on the content of the flavanols was investigated by HPLC. After a 5 min infusion of the tea leaves, the average concentrations of caffeine, catechin, EC, EGC, ECG and EGCG were found to be in the ranges 0.086–2.23, 0.113–2.94, 0.58–10.22, 0.19–24.9, 0.22–13.9 and 1.01–43.3 mg g−1, respectively. The contents of caffeine and catechins followed the sequence: EGCG > EGC > ECG > EC > C > caffeine. The method was applied satisfactorily for the analysis of (+)-catechin, even at trace and ultra trace concentrations of catechins. The method was rapid, accurate, reproducible and ideal for routine analysis.
Author: Pawel Bogdanski and Joanna Suliburska and Monika Szulinska and Marta Stepien and Danuta Pupek-Musialik and Anna Jablecka
Green tea (GT) consumption is known to be associated with enhanced cardiovascular and metabolic health. The purpose of this study is to examine the hypothesis that supplementation with GT alters insulin resistance and associated cardiovascular risk factors in obese, hypertensive patients. In a double-blind, placebo-controlled trial, 56 obese, hypertensive subjects were randomized to receive a daily supplement of 1 capsule that contained either 379 mg of GT extract (GTE) or a matching placebo, for 3 months. At baseline and after 3 months of treatment, the anthropometric parameters, blood pressure, plasma lipid levels, glucose levels, creatinine levels, tumor necrosis factor α levels, C-reactive protein levels, total antioxidant status, and insulin levels were assessed. Insulin resistance was evaluated according to the homeostasis model assessment–insulin resistance protocol. After 3 months of supplementation, both systolic and diastolic blood pressures had significantly decreased in the GTE group as compared with the placebo group (P < .01). Considerable (P < .01) reductions in fasting serum glucose and insulin levels and insulin resistance were observed in the GTE group when compared with the placebo group. Serum tumor necrosis factor α and C-reactive protein were significantly lower, whereas total antioxidant status increased in the GTE group compared with the placebo (P< .05). Supplementation also contributed to significant (P < .05) decreases in the total and low-density lipoprotein cholesterol and triglycerides, but an increase in high-density lipoprotein cholesterol. In conclusion, daily supplementation with 379 mg of GTE favorably influences blood pressure, insulin resistance, inflammation and oxidative stress, and lipid profile in patients with obesity-related hypertension.