DEPARTEMEN IT-KOM

The Role of Tea in Human Health: An UpdateDiane L. McKay, PhD, and Jeffrey B. Blumberg, PhD, FACNJournal of the American College of Nutrition, Vol. 21, No. 1, 113 (2002)GROUP 4 Alicia Yolandra Agil Dananjaya Cendy Prastiwi Dimas Satryo Bagus S. Ego Frendy Damara Meidiana PertiwiIntroductionTea is an important dietary source of flavanols and flavonols.Contrasting results have arisen from human studies of the relationship between tea and health, particularly the risk for cardiovascular disease and cancer.

Methods & limitationsMethods Review from in vitro and in vivo study to determine antioxidant activitiesReview form randomized clinical trial to exam the effect of tea and physiological responsesReview from human studies to exam the effect of tea on healthLimitationNot mentionedRESULTIn Vitro Antioxidant CapacityOxygen Radical Absorbance Capacity (ORAC) assay green and black tea have much higher antioxidant activity against peroxyl radicalsFerric Reducing Ability of Plasma (FRAP) assay total antioxidant capacity of green tea to be more potent than black teaTocol Equivalent Antioxidant Capacity (TEAC) assay ranked epicatechin and catechin among the most potent of 24 plant-derived polyphenolic flavonoids they evaluatedEx Vivo Antioxidant CapacitySingle dose of tea Improves plasma antioxidant capacity of healthy adults within 30-60 minutes after administerationRESULT contCARDIOVASCULAR DISEASECoronary Heart Diseasetea 44% lower risk of myocardial infarctionAtherosclerosistea inhibit development and progression of atherosclerosisHypertensionunrelatedEndothelial Cell Function tea reverses endothelial vasomotor dysfunctionLDL Oxidationextracts of black and green tea slow atherogenesis by reducing low density lipoprotein cholesterol (LDL), foam cell formation, and induction of proinflammatory cytokines

CANCERBreast Cancer UnrelatedEsophageal CancerUnrelatedLung Cancerblack tea reduced the risk of lung cancer by 66%Stomach Cancer black tea theaflavins induce apoptosis and inhibit the growth of human stomach cancer cellsColorectal CancerUnrelated, some studies show chemopreventive effect in GITBladder and Kidney CancersUnrelated, statistically not significantProstate CancerUnrelatedSkin Cancertea catechins inhibit the UVB-induced erythema response and DNA damageMucosa Leukoplakia topical administration black and green tea partial regression of this lesionRESULT contORAL HEALTHtea lower levels of dental caries Green tea inhibit oral bacteria (Escherichia coli,Streptococcus salivarius and Streptococcus mutans) Tea decoctions inhibit amylase activity in human saliva, reducing maltose release lowering the cariogenic potential of foodsBONE HEALTHtea greater bone mineral density THERMOGENESISgreen tea extract increased the energy expenditure control body weightCOGNITIVE FUNCTIONflavonoid reduction the risk of dementiaIRON STATUSBlack tea inhibit the bioavailability of non-heme ironIron deficiency anemia exacerbated by the regular consumption of tea with mealsKIDNEY STONES240 mL serving of tea consumed daily decreased the risk of kidney stonesDiscussionTea is source of flavanol and flavonol. In vitro and animal studies continue to provide strong evidence that tea polyphenol may posses the capacity to the pathogenesis of chronic diseases such as CVD and cancer. However, in vivo studies have various result. Eventhough there is no guideline regarding the tea consumption but there is also no evidence about the adverse effectconclusionsIn vitro and animal studies prove that tea can prevent some chronic diseases.The result of the study still cant be applied in human because epidemiological studies shown relationship between tea and health are inconsistent.Need further research to establish tea as primary and secondary prevention of chronic diseases in human.

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