***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: 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 r and omized 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 BACKGROUND Green tea is one of the most popular beverages in the world . It is believed to have beneficial effects in the prevention and treatment of many diseases , one of which is type 2 diabetes . The aim of the study is to examine the effect of a decaffeinated green tea extract ( GTE ) providing a daily dose of 856 mg of epigallocatechin gallate ( EGCG ) on obese individuals with type 2 diabetes . MATERIAL S AND METHODS The clinical trial was a r and omized , double-blind , placebo-controlled clinical trial conducted from December 2007 through November 2008 . The subjects were r and omly assigned to either receive 1,500 mg of a decaffeinated GTE or placebo daily for 16 weeks . Sixty-eight of 80 subjects , ages 20 - 65 years with BMI > 25 kg/m2 and type 2 diabetes for more than one year , completed this study .  Homeostasis model assessment for insulin resistance ( HOMA-IR ) was used as the major outcome measurement . At baseline and after 16 weeks of treatment , anthropometric measurements , fasting glucose , hemoglobin A1C percent ( HbA1C ) , hormone peptides , and plasma lipoproteins were measured from both groups . RESULTS No statistically significant differences were detected between the decaffeinated GTE and placebo groups in any measured variable . A statistically significant within-group 0.4-percent reduction in HbA1C ( from 8.4 to 8.0 % ) was observed after GTE treatment compared to baseline . Within-group comparison also revealed that the GTE group had significant reductions in waist circumference ( WC ) , HOMA-IR index , and insulin level , and a significant increase in the level of ghrelin . Within-group comparison of those in the placebo group showed a significant increase in the level of ghrelin . CONCLUSIONS This study found no statistical difference in any measured variable between the decaffeinated GTE and placebo groups ; however , there were some statistically significant within-group changes detected . More research is required to determine whether a decaffeinated GTE st and ardized for EGCG content will provide any clinical benefits in obese individuals with type 2 diabetes . Clinical Trial Registration NO : NCT00567905 We assessed the effect of ingestion of green tea ( GT ) extract along with a low-energy diet ( LED ) on resting energy expenditure ( REE ) , substrate oxidation and body weight as GT has been shown to increase energy expenditure and fat oxidation in the short term in both animals and people . Forty-six overweight women ( BMI 27.6 ( sd 1.8 ) kg/m2 ) were fed in energy balance from day 1 to day 3 , followed by a LED with GT ( 1125 mg tea catechins + 225 mg caffeine/d ) or placebo ( PLAC ) from day 4 to day 87 . Caffeine intake was st and ardised to 300 mg/d . Energy expenditure was measured on days 4 and 32 . Reductions in weight ( 4.19 ( sd 2.0 ) kg PLAC , 4.21 ( sd 2.7 ) kg GT ) , BMI , waist : hip ratio , fat mass and fat-free mass were not statistically different between treatments . REE as a function of fat-free mass and fat mass was significantly reduced over 32 d in the PLAC group ( P<0.05 ) but not in the GT group . Dietary restraint increased over time ( P<0.001 ) in both groups , whereas disinhibition and general hunger decreased ( P<0.05 ) . The GT group became more hungry over time and less thirsty , and showed increased prospect i ve food consumption compared with PLAC ( P<0.05 ) . Taken together , the ingestion of GT along with a LED had no additional benefit for any measures of body weight or body composition . Although the decrease in REE as a function of fat-free mass and fat mass was not significant with GT treatment , whereas it was with PLAC treatment , no significant effect of treatment over time was seen , suggesting that a robust limitation of REE reduction during a LED was not achieved by GT The consumption of green tea has been associated with cardiovascular and metabolic diseases . There have been some studies on the influence of green tea on the mineral status of obese subjects , but they have not yielded conclusive results . The aim of the present study is to examine the effects of green tea extract on the mineral , body mass , lipid profile , glucose , and antioxidant status of obese patients . A r and omized , double-blind , placebo-controlled study was conducted . Forty-six obese patients were r and omly assigned to receive either 379 mg of green tea extract , or a placebo , daily for 3 months . At baseline , and after 3 months of treatment , the anthropometric parameters , blood pressure , and total antioxidant status were assessed , as were the levels of plasma lipids , glucose , calcium , magnesium , iron , zinc , and copper . We found that 3 months of green tea extract supplementation result ed in decreases in body mass index , waist circumference , and levels of total cholesterol , low-density cholesterol , and triglyceride . Increases in total antioxidant level and in zinc concentration in serum were also observed . Glucose and iron levels were lower in the green tea extract group than in the control , although HDL-cholesterol and magnesium were higher in the green tea extract group than in the placebo group . At baseline , a positive correlation was found between calcium and body mass index , as was a negative correlation between copper and triglycerides . After 3 months , a positive correlation between iron and body mass index and between magnesium and HDL-cholesterol , as well as a negative correlation between magnesium and glucose , were observed . The present findings demonstrate that green tea influences the body 's mineral status . Moreover , the results of this study confirm the beneficial effects of green tea extract supplementation on body mass index , lipid profile , and total antioxidant status in patients with obesity This study was undertaken to investigate the effects of green tea on weight reduction in obese Thais . A r and omized , controlled trial involving 60 obese subjects ( body mass index , BMI > 25 kg/m2 ) was conducted . All subjects consumed a Thai diet containing 3 meals ( 8373.6 kJ/day ) for 12 weeks , prepared by the Nutritional Unit at Srinagarind Hospital . The diet contained 65 % carbohydrates , 15 % protein , and 20 % fat . Body weight , BMI , body composition , resting energy expenditure , and substrate oxidation were measured at baseline , and during weeks 4 , 8 , and 12 of the study . Serum levels of leptin and urine VMA were measured at baseline and during the 12th week . Differences over time and between the treatments ( green tea or placebo ) over time were determined using two-factor ANOVA with repeated measures . In comparing the two groups , differences in weight loss were 2.70 , 5.10 , and 3.3 kg during the 4th , 8th , and 12th weeks of the study , respectively . At the 8th and 12th weeks of the study , body weight loss was significantly different ( P < 0.05 ) . At the 8th week , the difference in resting energy expenditure was 183.38 kJ/day ( P < 0.001 ) , the difference in the respiratory quotient was 0.02 ( P < 0.05 ) , and no significant differences existed in satiety score , food intake , or physical activity . Urine VMA was significantly different in the 12th week of the study ( P < 0.05 ) . We conclude that green tea can reduce body weight in obese Thai subjects by increasing energy expenditure and fat oxidation Objective : To assess possibility of polyphenol-enriched oolong tea to reduce dietary lipid absorption in humans . Design : Twelve healthy adult subjects , three males and nine females , aged ( mean±s.d . ) 22.0±1.8 years , respectively , were r and omly divided into two groups . The participants were followed a double-blind placebo-controlled crossover design , including 7-day washout periods and 10-day treatment periods . During the treatment periods , subjects were given about 38 g of lipids from potato chips ( 19 g each within 30 min after lunch and dinner ) and total 750 ml beverages ( placebo- or polyphenol-enriched oolong tea ) at three meals . Blood sample s were collected for biochemical examination at days 8 , 18 , 25 and 35 of the study period . On the last 3 days of each treatment period , feces were collected to measure the excretion of lipids . Results : Lipid excretion into feces was significantly higher in the polyphenol-enriched oolong tea period ( 19.3±12.9 g/3day ) than in the placebo period ( 9.4±7.3 g/3day ) ( P<0.01 ) . Cholesterol excretion tended to increase in polyphenol-enriched oolong tea period ( 1.8±1.2 g/3day ) compared with that of placebo ( 1.2±0.6 g/3day ) ( P=0.056 ) . Conclusions : The results of this study indicated that polyphenol-enriched oolong tea could increase lipid excretion into feces when subjects took high-lipid diet BACKGROUND We investigated the effect of green tea extract ( GTE ) in arterial hypertension with high oxidative stress . Angiotensin ( Ang ) II induces endothelial dysfunction ( ED ) that is crucial for the development of atherosclerosis and hypertension . METHODS Male Sprague-Dawley rats , 13 weeks old , r and omly assigned to drinking water with or without GTE ( 6 mg/mL ) received a vehicle , a high ( 700 microg/kg/d ) or a low ( 350 microg/kg/d ) Ang II dose for 13 days , by osmotic mini-pumps . Blood pressure ( BP ) was measured with telemetry . After sacrifice , left ventricular ( LV ) mass index , small mesenteric artery media-to-lumen ratio , and concentration-response curves of phenylephrine-precontracted arteries to acetylcholine were evaluated . The effect of the superoxide dismutase ( SOD-1 ) analog tempol on artery responses to acetylcholine was assessed . Oxidative stress was measured by plasma hydroperoxides and nitrotyrosine levels . The mRNA of heme oxygenase 1 ( HO-1 ) , NADPH oxidase endothelial p22(phox ) subunit , and SOD-1 was also measured in the aorta . RESULTS Compared with vehicle high Ang II increased BP , LV mass index , media-to-lumen ratio , and hydroperoxide radicals . The GTE blunted these increases , prevented the increase in HO-1 , p22(phox ) , and SOD-1 mRNA in aorta caused by Ang II , and reduced them below baseline levels . Low Ang II dose increased BP values and plasma hydroperoxides only during the first week . Both Ang II doses shifted rightward the curves to acetylcholine ; this was prevented in vivo by GTE and abolished in vitro by tempol . CONCLUSIONS The GTE prevented hypertension and target organ damage induced by a high Ang II dose , likely by prevention or scavenging of superoxide anion generation Background Previous observational studies have indicated that green tea ( GT ) consumption is associated with reduced mortality from cerebral infa rct ion but not with mortality from cerebral hemorrhage . Therefore , we hypothesized that GT exerts a direct antiatherosclerotic effect without any effect on hypertension . To investigate this hypothesis , we focused on adiponectin that seems to be among the several key players in atherosclerosis 
    Output:
    
Conclusion The present meta- analysis suggests that green tea and its catechins may improve blood pressure , and the effect may be greater in those with systolic blood pressure ≥130 mm Hg .
The meta- analysis also suggests that green tea catechins may improve total and low-density lipoprotein cholesterol