The Effects of Epigallocatechin-3-Gallate on Thermogenesis and Fat Oxidation in Obese Men: A Pilot Study Health effects of green tea catechins in overweight and obese men: a randomised controlled cross-over trial. Green Tea Extract and Catechol-O-Methyltransferase Genotype Modify Fasting Serum Insulin and Plasma Adiponectin Concentrations in a Randomized Controlled Trial of Overweight and Obese Postmenopausal Women. Effects of green tea on weight maintenance after body-weight loss. Epigallocatechin-3-gallate and postprandial fat oxidation in overweight/obese male volunteers: a pilot study Effect of green tea on resting energy expenditure and substrate oxidation during weight loss in overweight females. Effectiveness of green tea on weight reduction in obese Thais: A randomized, controlled trial Body weight loss and weight maintenance in relation to habitual caffeine intake and green tea supplementation. Recent findings of green tea extract AR25 (Exolise) and its activity for the treatment of obesity. Green tea catechin plus caffeine supplementation to a high-protein diet has no additional effect on body weight maintenance after weight loss. Beneficial effects of oolong tea consumption on diet-induced overweight and obese subjects Effects of Chinese Green Tea on Weight, and Hormonal and Biochemical Profiles in Obese Patients With Polycystic Ovary Syndrome—A Randomized Placebo-Controlled Trial Effects of encapsulated green tea and Guarana extracts containing a mixture of epigallocatechin-3-gallate and caffeine on 24 h energy expenditure and fat oxidation in men. Diet supplementation with green tea extract epigallocatechin gallate prevents progression to glucose intolerance in db/db mice Long-Term Supplementation of Green Tea Extract Does Not Modify Adiposity or Bone Mineral Density in a Randomized Trial of Overweight and Obese Postmenopausal Women. Effects of Green Tea Supplementation on Elements, Total Antioxidants, Lipids, and Glucose Values in the Serum of Obese Patients Effects of catechin enriched green tea on body composition.
Objectives : The development of obesity is characterized by an increase in adipose tissue mass and by concomitant and profound changes in almost all organ functions leading to diseases such as hypertension , diabetes mellitus and coronary heart disease . Recent data from human studies indicate that the consumption of green tea and green tea extracts may help reduce body weight , mainly body fat , by increasing postpr and ial thermogenesis and fat oxidation . However , human studies investigating the metabolic effects of the most predominant tea catechin , EGCG , alone are absent . Methods : In a r and omized double blind , placebo-controlled , cross-over pilot study , six overweight men were given 300 mg EGCG/d for 2d . Fasting and postpr and ial changes in energy expenditure ( EE ) and substrate oxidation were assessed . Results : Resting EE did not differ significantly between EGCG and placebo treatments , although during the first postpr and ial monitoring phase , respiratory quotient ( RQ ) values were significantly lower with EGCG compared to the placebo . Conclusions : These findings suggest that EGCG alone has the potential to increase fat oxidation in men and may thereby contribute to the anti-obesity effects of green tea . However , more studies with a greater sample size and a broader range of age and BMI are needed to define the optimum dose Regular consumption of green tea may be cardioprotective . In the present study we investigated the health effects of dietary supplementation with green tea catechins and the potential modifying effect of the catechol-O-methyltransferase ( COMT ) Val/Met genotype . Subjects ( sedentary males , aged 40 - 69 years , with BMI ≥ 28 and ≤ 38 kg/m(2 ) ) were r and omly assigned to consume decaffeinated green tea extract ( DGT ; 530 mg containing about 400 mg total catechins/capsule , twice daily ) and placebo in a complete cross-over design . Ambulatory blood pressure and biomarkers of metabolic function ( cholesterol , TAG , glucose and insulin ) were measured at weeks 0 and 6 . Although a marked increase in the concentration of plasma epigallocatechin gallate ( EGCG ) , urinary epigallocatechin ( EGC ) and urinary 4'-O-methyl EGC was found after DGT treatment , no effect on blood pressure or biomarkers of metabolic function was observed . However , a period × treatment interaction ( P < 0·05 ) was detected for body-weight change . Despite a similar increase in estimated energy intake during intervention period 1 , body weight decreased by 0·64 ( sd 2·2 ) kg and increased by 0·53 ( sd 1·9 ) kg in the DGT and placebo groups , respectively ( P = 0·025 ) , suggesting a protective effect of green tea catechins on weight gain . Additionally , the COMT Val/Met genotype influenced urinary accumulation of EGC and 4'-O-methyl EGC ( P < 0·01 ) . Mean concentrations were lower in individuals homozygous for the high-activity G-allele , possibly reflecting increased metabolic flux and a more rapid conversion to downstream metabolic species , compared with individuals carrying at least one copy of the low-activity A-allele . Additional studies are needed to confirm these findings and further explore the modifying effect of genotype BACKGROUND Green tea consumption has been associated with favorable changes in body weight and obesity-related hormones , although it is not known whether these changes result from green tea polyphenols or caffeine . OBJECTIVE We examined the impact of decaffeinated green tea extract ( GTE ) containing 843 mg of (-)-epigallocatechin-3-gallate on anthropometric variables , obesity-associated hormones , and glucose homeostasis . METHODS The Minnesota Green Tea Trial was a 12-mo r and omized , double-blind , placebo-controlled clinical trial of 937 healthy postmenopausal women assigned to either decaffeinated GTE ( 1315 mg total catechins/d ) or a placebo  , stratified by catechol-O-methyltransferase ( COMT ) genotype . This study was conducted in a subset of 237 overweight and obese participants [ body mass index ( BMI ) ≥25 kg/m(2 ) ] . RESULTS No changes in energy intake , body weight , BMI , or waist circumference ( WC ) were observed over 12 mo in women taking GTE ( n = 117 ) or placebo ( n = 120 ) . No differences were seen in circulating leptin , ghrelin , adiponectin , or glucose concentrations at month 12 . Participants r and omly assigned to GTE with baseline insulin ≥10 μIU/mL ( n = 23 ) had a decrease in fasting serum insulin from baseline to month 12 ( -1.43 ± 0.59 μIU/mL ) , whereas those r and omly assigned to placebo with baseline insulin ≥10 μIU/mL ( n = 19 ) had an increase in insulin over 12 mo ( 0.55 ± 0.64 μIU/mL , P < 0.01 ) . Participants with the homozygous high-activity ( G/G ) form of COMT had significantly lower adiponectin ( 5.97 ± 0.50 compared with 7.58 ± 0.53 μg/mL , P = 0.03 ) and greater insulin concentrations ( 7.63 ± 0.53 compared with 6.18 ± 0.36 μIU/mL , P = 0.02 ) at month 12 compared with those with the low-activity ( A/A ) genotype , regardless of treatment group . CONCLUSIONS Decaffeinated GTE was not associated with reductions in body weight , BMI , or WC and did not alter energy intake or mean hormone concentrations in healthy postmenopausal women over 12 mo . GTE decreased fasting insulin concentrations in those with elevated baseline fasting concentrations . The high-activity form of the COMT enzyme may be associated with elevations in insulin and a reduction in adiponectin concentrations over time . This trial was registered at http://www . clinical trials.gov as NCT00917735 The present study was conducted to investigate whether green tea may improve weight maintenance by preventing or limiting weight regain after weight loss of 5 to 10 % in overweight and moderately obese subjects . The study had a r and omised , parallel , placebo-controlled design . A total of 104 overweight and moderately obese male and female subjects ( age 18 - 60 years ; BMI 25 - 35 kg/m(2 ) ) participated . The study consisted of a very-low-energy diet intervention ( VLED ; 2.1 MJ/d ) of 4 weeks followed by a weight-maintenance period of 13 weeks in which the subjects received green tea or placebo . The green tea contained caffeine ( 104 mg/d ) and catechins ( 573 mg/d , of which 323 mg was epigallocatechin gallate ) . Subjects lost 6.4 ( sd 1.9 ) kg or 7.5 ( sd 2.2 ) % of their original body weight during the VLED ( P<0.001 ) . Body-weight regain was not significantly different between the green tea and the placebo group ( 30.5 ( sd 61.8 ) % and 19.7 ( sd 56.9 ) % , respectively ) . In the green tea treatment , habitual high caffeine consumption was associated with a higher weight regain compared with habitual low caffeine consumption ( 39 ( sd 17 ) and 16 ( sd 11 ) % , respectively ; P<0.05 ) . We conclude that weight maintenance after 7.5 % body-weight loss was not affected by green tea treatment and that habitual caffeine consumption affected weight maintenance in the green tea treatment Objectives : Drinking green tea is associated with many health benefits , including increased fat oxidation . We tested the hypothesis that epigallocatechin-3-gallate ( EGCG ) , the main green tea catechin , increases  fat oxidation in obese men . Methods : Ten healthy overweight/obese males ( body mass index 31.3±0.8 kg/m2 ) were studied in a r and omized , placebo-controlled , double-blind crossover trial . Study supplements were low EGCG ( 300 mg ) , high EGCG ( 600 mg ) , caffeine ( 200 mg ) , EGCG/caffeine ( 300 mg/200 mg ) or placebo and were taken orally for 3 days . At the third day of supplementation , O2 consumption and CO2 production was measured by indirect calorimetry to assess energy expenditure and fat oxidation over 4 h each after overnight fasting and after a st and ardized test meal . Results : Energy expenditure was not affected by any supplementation , neither after overnight fasting nor after the test meal . During the first 2 h after overnight fasting , fat oxidation increased by 7.7 ( not significant , NS ) , 15.2 ( NS ) , 26.3 ( P<0.05 vs placebo ) and 35.4 % ( P<0.01 vs placebo and low EGCG ) , for low EGCG , high EGCG , caffeine and EGCG/caffeine , respectively . During the first 2 h after the meal , the mean increase in fat oxidation was 33.3 ( P<0.05 vs placebo ) , 20.2 ( NS ) , 34.5 ( P<0.05 vs placebo ) and 49.4 % ( P<0.05 vs placebo ) for low EGCG , high EGCG , caffeine and EGCG/caffeine , respectively . Conclusions : Low EGCG increases postpr and ial fat oxidation  in obese men and this to the same extent as 200 mg caffeine , whereas high EGCG does not exert this effect . Fasting fat oxidation is increased only by caffeine ( with or without EGCG ) . There is no synergism of low EGCG and 200 mg caffeine . Energy expenditure is not affected by EGCG 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 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 Investigation of the effect of a green tea-caffeine mixture on weight maintenance after body weight loss in moderately obese subjects in relation to habitual caffeine intake . RESEARCH METHODS AND PROCEDURES A r and omized placebo-controlled double blind parallel trial in 76 overweight and moderately obese subjects , ( BMI , 27.5 + /- 2.7 kg/m2 ) matched for sex , age , BMI , height , body mass , and habitual caffeine intake was conducted . A very low energy diet intervention during 4 weeks was followed by 3 months of weight maintenance ( WM ) ; during the WM period , the subjects received a green tea-caffeine mixture ( 270 mg epigallocatechin gallate + 150 mg caffeine per day ) or placebo . RESULTS Subjects lost 5.9 + /-1.8 ( SD ) kg ( 7.0 + /- 2.1 % ) of body weight ( p < 0.001 ) . At baseline , satiety was positively , and in women , leptin was inversely , related to subjects ' habitual caffeine consumption ( p < 0.01 ) . High caffeine consumers reduced weight , fat mass , and waist circumference more than low caffeine consumers ; resting energy expenditure was reduced less and respiratory quotient was reduced more during weight loss ( p < 0.01 ) . In the low caffeine consumers , during WM , green tea still reduced body weight , waist , respiratory quotient and body fat , whereas resting energy expenditure was increased compared with a restoration of these variables with placebo ( p < 0.01 ) . In the high caffeine consumers , no effects of the green tea-caffeine mixture were observed during WM . DISCUSSION High caffeine intake was associated with weight loss through thermogenesis and fat oxidation and with suppressed leptin in women . In habitual low caffeine consumers , the green tea-caffeine mixture improved WM , partly through thermogenesis and fat oxidation The green tea extract AR25 is an 80 % ethanolic dry extract st and ardized at 25 % catechins expressed as epigallocatechin gallate ( EGCG ) . In vitro , green tea extract AR25 exerts a direct inhibition of gastric and pancreatic lipases and a stimulation of thermogenesis . In an open study , the effects of extract AR25 were evaluated in moderately obese patients . After 3 months , body weight was decreased by 4.6 % and waist circumference by 4.48 % . These results suggest the green tea extract AR25 to be a natural product for the treatment of obesity , which exerts its activity by several ways : inhibition of lipases and stimulation of thermogenesis BACKGROUND Green tea ( epigallocatechin gallate + caffeine ) and protein each were shown to improve body weight maintenance after weight loss . OBJECTIVE We investigated the effect of a green tea-caffeine mixture added to a high-protein ( HP ) diet on weight maintenance ( WM ) after body weight loss in moderately obese subjects . DESIGN A r and omized , placebo-controlled , double-blind parallel trial was conducted in 80 overweight and moderately obese subjects [ age ( mean + /- SD ) : 44 + /- 2 y ; body mass index ( BMI ; in kg/m(2 ) ) : 29.6 + /- 2.0 ] matched for sex , age , BMI , height , body mass , and with a habitually low caffeine intake . A very-low-energy diet intervention during 4 wk was followed by 3 mo of WM ; during the WM period , the subjects received a green tea-caffeine mixture ( 270 mg epigallocatechin gallate + 150 mg caffeine/d ) or placebo , both in addition to an adequate protein ( AP ) diet ( 50 - 60 g protein/d ) or an HP diet ( 100 - 120 g protein/d ) . RESULTS Subjects lost 7.0 + /- 1.6 kg , or 8.2 + /- 2.0 % , body weight ( P < 0.001 ) . During the WM phase , WM , resting energy expenditure , and fat-free mass ( FFM ) increased relatively in both the HP groups and in the AP + green tea-caffeine mixture group ( P < 0.05 ) , whereas respiratory quotient and body fat mass decreased , all compared with the AP + placebo group . Satiety increased only in both HP groups ( P < 0.05 ) . The green tea-caffeine mixture was only effective with the AP diet . CONCLUSION The green tea-caffeine mixture , as well as the HP diet , improved WM independently through thermogenesis , fat oxidation , sparing FFM , and , for the HP diet , satiety ; a possible synergistic effect failed to appear Objective To determine the anti-obesity effects of oolong tea on diet-induced overweight or obesity . Methods A total of 8 g of oolong tea a day for 6 weeks was ingested by 102 diet-induced overweight or obese subjects . The body fat level of the subjects was determined at the same time by taking body weight , height and waist measurements . The thickness of the subcutaneous fat layer was also determined on the abdomen 3 cm to the right of the navel by the ultrasonic echo method . On the other h and , effects of oolong tea ingestion on plasma triglyceride ( TG ) and total cholesterol ( TC ) were determined . Inhibitions of pancreatic lipase by oolong tea extract and catechins in vitro were also determined . Results A total of 70 % of the severely obese subjects did show a decrease of more than 1 kg in body weight , including 22 % who lost more than 3 kg . Similarly , 64 % of the obese subjects and 66 % of the overweight subjects lost more than 1 kg during the experiment , and the subcutaneous fat content decreased in 12 % of the subjects . The correlation between weight loss and subcutaneous fat decrease in men ( r=0.055 ) was obviously lower than that in women ( r=0.440 , P<0.01 ) . Body weight loss was signifificantly related to the decrease of the waist size in men ( r=0.730 , P<0.01 ) and women ( r=0.480 , P<0.01 ) . Also , the correlation between subcutaneous fat reduction and decreased waist size was signifificant in women ( r=0.554 , P<0.01 ) , but not in men ( r=0.050 , P>0.05 ) . Moreover , the plasma levels of TG and TC of the subjects with hyperlipidemia were remarkably decreased after ingesting oolong tea for 6 weeks . In vitro assays for the inhibition of pancreatic lipase by oolong tea extract and catechins suggest that the mechanism for oolong tea to prevent hyperlipidemia may be related to the regulative action of oolong tea catechins in lipoprotein activity . Conclusions Oolong tea could decrease body fat content and reduce body weight through improving lipid metabolism . Chronic consumption of oolong tea may prevent against obesity Objectives : To study the effects of green tea on body weight , and biochemical and hormonal profiles in obese Chinese women with polycystic ovary syndrome ( PCOS ) . Methods : Thirty-four obese Chinese women with PCOS were r and omized into either treatment with green tea capsules or placebo for 3 months . The anthropomentric measurements , and biochemical and hormonal profiles before and after treatment in each group were compared . Results : The body weight of the green tea group decreased by a nonsignificant 2.4 % after treatment ; whereas the body weight , body mass index ( BMI ) , and body fat content of the control group were significantly higher after 3 months . There were no differences in any of the hormone levels measured in either group . The biochemical profiles of the two groups were also similar except that there was a small but significant rise in the triglyceride level in the green tea group . Fewer patients in the green tea group remained amenorrhoeic , but this was not significantly different from the control group . Conclusions : Green tea supplementation did not significantly reduce body weight in obese women with PCOS , nor did it alter the glucose or lipid metabolism It has been reported that green tea has a thermogenic effect , due to its caffeine content and probably also to the catechin , epigallocatechin-3-gallate ( EGCG ) . The main aim of the present study was to compare the effect of a mixture of green tea and Guarana extracts containing a fixed dose of caffeine and variable doses of EGCG on 24 h energy expenditure and fat oxidation .  Fourteen subjects took part to this r and omized , placebo-controlled , double-blind , cross-over study . Each subject was tested five times in a metabolic chamber to measure 24 h energy expenditure , substrate oxidation and blood pressure . During each stay , the subjects ingested a capsule of placebo or capsules containing 200 mg caffeine and a variable dose of EGCG ( 90 , 200 , 300 or 400 mg ) three times daily , 30 min before st and ardized meals . Twenty-four hour energy expenditure increased significantly by about 750 kJ with all EGCG-caffeine mixtures compared with placebo . No effect of the EGCG-caffeine mixture was observed for lipid oxidation . Systolic and diastolic blood pressure increased by about 7 and 5 mmHg , respectively , with the EGCG-caffeine mixtures compared with placebo . This increase was significant only for 24 h diastolic blood pressure . The main finding of the study was the increase in 24 h energy expenditure with the EGCG-caffeine mixtures . However , this increase was similar with all doses of EGCG in the mixtures Background Green tea was suggested as a therapeutic agent for the treatment of diabetes more than 70 years ago , but the mechanisms behind its antidiabetic effect remains elusive . In this work , we address this issue by feeding a green tea extract ( TEAVIGO ™ ) with a high content of epigallocatechin gallate ( EGCG ) or the thiazolidinedione PPAR-γ agonist rosiglitazone , as positive control , to db/db mice , an animal model for diabetes . Methods Young ( 7 week-old ) db/db mice were r and omized and assigned to receive diets supplemented with or without EGCG or rosiglitazone for 10 weeks . Fasting blood glucose , body weight and food intake was measured along the treatment . Glucose and insulin levels were determined during an oral glucose tolerance test after 10 weeks of treatment . Pancreata were sample d at the end of the study for blinded histomorphometric analysis . Islets were isolated and their mRNA expression analyzed by quantitative RT-PCR . Results The results show that , in db/db mice , EGCG  improves glucose tolerance and increases glucose-stimulated insulin secretion . EGCG supplementation reduces the number of pathologically changed islets of Langerhans , increases the number and the size of islets , and heightens pancreatic endocrine area . These effects occurred in parallel with a reduction in islet endoplasmic reticulum stress markers , possibly linked to the antioxidative capacity of EGCG . Conclusions This study shows that the green tea extract EGCG markedly preserves islet structure and enhances glucose tolerance in genetically diabetic mice . Dietary supplementation with EGCG could potentially contribute to nutritional strategies for the prevention and treatment of type 2 diabetes BACKGROUND Green tea extract ( GTE ) consumption has been linked to favorable changes in adiposity and bone mineral density ( BMD ) , although it is unknown if these effects are due to green tea catechins or caffeine . The catechol-O-methyltransferase ( COMT ) genotype may also modify these associations . OBJECTIVE We examined the impact of decaffeinated GTE on body composition ( using dual-energy X-ray absorptiometry ) and obesity-associated hormones . METHODS The Minnesota Green Tea Trial was a 12-mo r and omized , double-blind , placebo-controlled clinical trial in 937 postmenopausal women ( aged 50 - 70 y ) assigned to receive either GTE containing 843 mg (-)-epigallocatechin-3-gallate or placebo . This sub study was conducted in 121 overweight/obese participants [ body mass index ( BMI ) ( kg/m(2 ) ) ≥25.0 ] . RESULTS There were no differences in changes in BMI ( -0.13 ± 0.11 compared with -0.05 ± 0.11 ; P = 0.61 ) , total fat mass ( -0.30 ± 0.16 compared with -0.12 ± 0.15 kg ; P = 0.40 ) , percentage of body fat ( -0.15 % ± 0.17 % compared with -0.15 % ± 0.16 % ; P = 0.99 ) , or BMD ( -0.006 ± 0.002 compared with -0.003 ± 0.002 g/cm(2 ) ; P = 0.49 ) over 12 mo between women taking GTE ( n = 61 ) and those taking a placebo ( n = 60 ) . Interactions were observed between treatment and time for gynoid percentage of fat ( % fat ) and tissue % fat . Gynoid % fat increased from baseline to month 12 in the placebo group as baseline BMI increased and decreased over time as baseline BMI increased in the GTE group ( P-interaction = 0.02 ) . Tissue % fat increased from baseline to month 12 in the placebo group as baseline BMI increased . In the GTE  group , tissue % fat decreased during the intervention as baseline BMI increased ( P-interaction = 0.04 ) . No changes were seen in circulating leptin , ghrelin , adiponectin , or insulin concentrations . COMT genotype did not modify the effect of GTE on any variable . CONCLUSIONS Decaffeinated GTE was not associated with overall reductions in adiposity or improvements in BMD in overweight/obese postmenopausal women . However , GTE may be beneficial for reduction in tissue and gynoid % fat in individuals with higher BMI . This clinical trial was registered at www . clinical trials.gov as NCT00917735 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 Obesity is a major health problem in the developed and developing world . Many " functional " foods and ingredients are advocated for their effects on body composition but few have consistent scientific support for their efficacy . However , an increasing amount of mechanistic and clinical evidence is building for green tea ( GT ) . This experiment was therefore undertaken to study the effects of a high-catechin GT on body composition in a moderately overweight Chinese population . In a r and omized placebo-controlled trial , 182 moderately overweight Chinese subjects , consumed either two servings of a control drink ( C ; 30 mg catechins , 10 mg caffeine/day ) , one serving of the control drink and one serving of an extra high-catechin GT1 ( 458 mg catechins , 104 mg caffeine/day ) , two servings of a high-catechin GT2 ( 468 mg catechins , 126 mg caffeine/day ) or two servings of the extra high-catechin GT3 ( 886 mg catechins , 198 mg caffeine/day ) for 90 days . Data were collected at 0 , 30 , 60 , and 90 days . We observed a decrease in estimated intra-abdominal fat ( IAF ) area of 5.6 cm(2 ) in the GT3 group . In addition , we found decreases of 1.9 cm in waist circumference and 1.2 kg body weight in the GT3 group vs. C ( P < 0.05 ) . We also observed reductions in total body fat ( GT2 , 0.7 kg , P < 0.05 ) and body fat % ( GT1 , 0.6 % , P < 0.05 ) . We conclude that consumption of two servings of an extra high-catechin GT leads to improvements in body composition and reduces abdominal fatness in moderately overweight Chinese subjects
Research has been very varied , however , daily consumption of green tea with doses of EGCG between 100 and 460 mg/day has shown greater effectiveness on body fat and body weight reduction in intervention periods of 12 weeks or more .
In addition , the use of caffeine doses between 80 and 300 mg/day has been shown to be an important factor for this effects , when the participants did not have a high caffeine intake ( > 300 mg/day ) prior to the intervention
The prevalence and incidence of overweight and obesity worldwide continues to increase , as well as diseases related to these conditions .
This is attributed to an increase in energy intake and a decrease in energy expenditure .
Consumption of green tea has been linked to a reduction in body fat and body weight .
However , research on green tea has been very diverse .
This review assesses the investigations that have been made with green tea and its epigallocatechin gallato ( EGCG ) content , evaluating its effect on body fat and body weight in humans .