***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 
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    Input: CONTEXT Few cardiovascular outcome data are available for blacks with hypertension treated with angiotensin-converting enzyme ( ACE ) inhibitors or calcium channel blockers ( CCBs ) . OBJECTIVE To determine whether an ACE inhibitor or CCB is superior to a thiazide-type diuretic in reducing cardiovascular disease ( CVD ) incidence in racial subgroups . DESIGN , SETTING , AND PARTICIPANTS Prespecified subgroup analysis of ALLHAT , a r and omized , double-blind , active-controlled , clinical outcome trial conducted between February 1994 and March 2002 in 33,357 hypertensive US and Canadian patients aged 55 years or older ( 35 % black ) with at least 1 other cardiovascular risk factor . INTERVENTIONS Antihypertensive regimens initiated with a CCB ( amlodipine ) or an ACE inhibitor ( lisinopril ) vs a thiazide-type diuretic ( chlorthalidone ) . Other medications were added to achieve goal blood pressures ( BPs ) less than 140/90 mm Hg . MAIN OUTCOME MEASURES The primary outcome was combined fatal coronary heart disease ( CHD ) or nonfatal myocardial infa rct ion ( MI ) , analyzed by intention-to-treat . Secondary outcomes included all-cause mortality , stroke , combined CVD ( CHD death , nonfatal MI , stroke , angina , coronary revascularization , heart failure [ HF ] , or peripheral vascular disease ) , and end-stage renal disease . RESULTS No significant difference was found between treatment groups for the primary CHD outcome in either racial subgroup . For amlodipine vs chlorthalidone only , HF was the only prespecified clinical outcome that differed significantly ( overall : relative risk [ RR ] , 1.37 ; 95 % confidence interval [ CI ] , 1.24 - 1.51 ; blacks : RR , 1.46 ; 95 % CI , 1.24 - 1.73 ; nonblacks : RR , 1.32 ; 95 % CI , 1.17 - 1.49 ; P<.001 for each comparison ) with no difference in treatment effects by race ( P = .38 for interaction ) . For lisinopril vs chlorthalidone , results differed by race for systolic BP ( greater decrease in blacks with chlorthalidone ) , stroke , and combined CVD outcomes ( P<.001 , P = .01 , and P = .04 , respectively , for interactions ) . In blacks and nonblacks , respectively , the RRs for stroke were 1.40 ( 95 % CI , 1.17 - 1.68 ) and 1.00 ( 95 % CI , 0.85 - 1.17 ) and for combined CVD were 1.19 ( 95 % CI , 1.09 - 1.30 ) and 1.06 ( 95 % CI , 1.00 - 1.13 ) . For HF , the RRs were 1.30 ( 95 % CI , 1.10 - 1.54 ) and 1.13 ( 95 % CI , 1.00 - 1.28 ) , with no significant interaction by race . Time-dependent BP adjustment did not significantly alter differences in outcome for lisinopril vs chlorthalidone in blacks . CONCLUSIONS In blacks and nonblack subgroups , rates were not lower in the amlodipine or lisinopril groups than in the chlorthalidone group for either the primary CHD or any other prespecified clinical outcome , and diuretic-based treatment result ed in the lowest risk of heart failure . While the improved outcomes with chlorthalidone were more pronounced for some outcomes in blacks than in nonblacks , thiazide-type diuretics remain the drugs of choice for initial therapy of hypertension in both black and nonblack hypertensive patients ABSTRACT Introduction : The use of herbal medicines including different types of tea is among the different strategies for preventing and controlling the side-effects of diabetes . The aim of the present study was to compare the effect of sour tea and green tea on mildly hypertensive patients with diabetes . Methods : The present study was a r and omized clinical trial in which 100 mildly hypertensive patients with diabetes were r and omly assigned into sour tea group ( ST ) and green tea group ( GT ) . They were instructed to drink sour tea and green tea infusion , respectively , three times a day 2 hr after each meal for 4 weeks . The participants ’ blood pressure was measured at days 1 , 15 , and at the end of study . Results : The systolic pressure of both groups statistically decreased at the end of the study ; it decreased from 123.1 ± 15.5 to 116.8 ± 16.3 mmHg in the ST and from 119.4 ± 15.1 to 114.8 ± 15.9 mmHg in the GT . The diastolic pressure of both groups statistically decreased by the end of the study ; it decreased from 79.4 ± 11.1 to 74.5 ± 9.3 mmHg in the ST and from 78.9 ± 8.3 to 75.3 ± 7.7 mmHg in the GT . The therapeutic effectiveness of tea drinking by the end of intervention was 43.5 % in the ST and 39.6 % in the GT compared to the beginning . Conclusions : The present study revealed that mildly hypertensive type 2 diabetic individuals who drink three glasses of green or sour tea daily for 4 weeks show significant decreased systolic and diastolic blood pressures Evidence suggests that berries contain bioactive compounds , which reduce certain cancers and hypertension . Our hypothesis was that daily blueberry ( BB ) consumption would increase natural killer ( NK ) cells and plasma redox capacity and reduce blood pressure , augmentation index ( AIx ) , central pulse wave velocity , and aortic systolic pressures ( ASPs ) . Twenty-five men and postmenopausal women aged 18 to 50 years were recruited and r and omized to BB ( n , 13 ) or  placebo groups ( n , 12 ) . Participants were provided with BB ( equivalent to 250 g berries ) or placebo powders each day for 6 weeks . Blood pressure , vascular performance testing , and blood sample s were taken at baseline ( presupplementation ) . Participants returned after 6 weeks and repeated all procedures . Presupplementation to postsupplementation comparisons for the main effects of treatment , time , and treatment-time interaction were made using a 2 ( treatment ) × 2 ( times ) repeated- measures analysis of variance for all vascular measures , redox status , and NK cell counts . Anthropometric measures were compared using t tests . Body mass , composition , and overall blood pressures were not affected in either group . Overall , AIx and ASPs were decreased in BB ( treatment effect , P = .024 and P = .046 , respectively ) . Plasma redox was not affected . Absolute NK cells were increased in BB ( time , P = .001 and interaction , P = .012 ) . Subjects ( n , 9 ) with prehypertensive pressures ( ≥120/80 mm Hg , respectively ) were examined as a subset using t tests and exhibited significant reductions in diastolic pressure ( P = .038 ) from presupplementation to postsupplementation in BB . We conclude that BB ingestion for 6 weeks increases NK cells and reduces AIx , ASP , and diastolic pressures in sedentary males and females Dietary supplementation with whole blueberries in a pre clinical study result ed in a reduction in glucose concentrations over time . We sought to evaluate the effect of daily dietary supplementation with bioactives from blueberries on whole-body insulin sensitivity in men and women . A double-blinded , r and omized , and placebo-controlled clinical study design was used . After screening to resolve study eligibility , baseline ( wk 0 ) insulin sensitivity was measured on 32 obese , nondiabetic , and insulin-resistant subjects using a high-dose hyperinsulinemic-euglycemic clamp ( insulin infusion of 120 mU(861 pmol)⋅m(-2)⋅min(-1 ) ) . Serum inflammatory biomarkers and adiposity were measured at baseline . At the end of the study , insulin sensitivity , inflammatory biomarkers , and adiposity were reassessed . Participants were r and omized to consume either a smoothie containing 22.5 g blueberry bioactives ( blueberry group , n = 15 ) or a smoothie of equal nutritional value without added blueberry bioactives ( placebo group , n = 17 ) twice daily for 6 wk . Both groups were instructed to maintain their body weight by reducing ad libitum intake by an amount equal to the energy intake of the smoothies . Participants ' body weights were evaluated weekly and 3-d food records were collected at baseline , the middle , and end of the study . The mean change in insulin sensitivity improved more in the blueberry group ( 1.7 ± 0.5 mg⋅kg FFM(-1)⋅min(-1 ) ) than in the placebo group ( 0.4 ± 0.4 mg⋅kg FFM(-1)⋅min(-1 ) ) ( P = 0.04 ) . Insulin sensitivity was enhanced in the blueberry group at the end of the study without significant changes in adiposity , energy intake , and inflammatory biomarkers . In conclusion , daily dietary supplementation with bioactives from whole blueberries  improved insulin sensitivity in obese , nondiabetic , and insulin-resistant participants BACKGROUND Dietary flavonoids have beneficial effects on  blood pressure  in intervention setting s , but there is limited information on habitual intake and risk of hypertension in population -based studies . OBJECTIVE We examined the association between habitual flavonoid intake and  incident hypertension  in a prospect i ve study in men and women . DESIGN A total of 87,242 women from the Nurses ' Health Study ( NHS ) II , 46,672 women from the NHS I , and 23,043 men from the Health Professionals Follow-Up Study ( HPFS ) participated in the study . Total flavonoid and subclass intakes were calculated from semiquantitative food-frequency question naires collected every 4 y by using an up date d and extended US Department of Agriculture data base . RESULTS During 14 y of follow-up , 29,018 cases of hypertension in women and 5629 cases of hypertension in men were reported . In pooled multivariate-adjusted analyses , participants in the highest quintile of anthocyanin intake ( predominantly from blueberries and strawberries ) had an 8 % reduction in risk of hypertension [ relative risk ( RR ) : 0.92 ; 95 % CI : 0.86 , 0.98 ; P < 0.03 ] compared with that for participants in the lowest quintile of anthocyanin intake ; the risk reduction was 12 % ( RR : 0.88 ; 95 % CI : 0.84 , 0.93 ; P < 0.001 ) in participants ≤60 y of age and 0.96 ( 0.91 , 1.02 ) in participants > 60 y of age ( P for age interaction = 0.02 ) . Although intakes of other subclasses were not associated with hypertension , pooled analyses for individual compounds suggested a 5 % ( 95 % CI : 0.91 , 0.99 ; P = 0.005 ) reduction in risk for the highest compared with the lowest quintiles of intake of the flavone apigenin . In participants ≤60 y of age , a 6 % ( 95 % CI : 0.88 , 0.97 ; P = 0.002 ) reduction in risk was observed for the flavan-3-ol catechin when the highest and the lowest quintiles were compared . CONCLUSIONS Anthocyanins and some flavone and flavan-3-ol compounds may contribute to the prevention of hypertension . These vasodilatory properties may result from specific structural similarities ( including the B-ring hydroxylation and methyoxylation pattern ) OBJECTIVE Evaluation of the vitro antioxidant activity of green and black tea , their in vivo effect on plasma antioxidant potential in man and the effect of milk addition . DESIGN The antioxidant activity of the tea , with and without milk , was tested in vitro by measuring the length of the peroxyl radical induced lag-phase . The in vivo activity was tested on two groups of five healthy adults . Each group ingested 300 ml of either black or green tea , after overnight fast . The experiment was repeated on a separate day , adding 100 ml whole milk to the tea ( ratio 1:4 ) . Five subjects acted as controls . The human plasma antioxidant capacity ( TRAP ) was measured before and 30 , 50 and 80 min from the ingestion of tea . RESULTS Both teas inhibited the in vitro peroxidation in a dose-dependent manner . Green tea was sixfold more potent than black tea . The addition of milk to either tea did not appreciably modify their in vitro antioxidant potential . In vivo , the ingestion of tea produced a significant increase of TRAP ( P < 0.05 ) , similar in both teas , which peaked at 30 - 50 min . When tea was consumed with milk , their in vivo activity was totally inhibited . CONCLUSIONS The paper shows that tea possesses a 
    Output:
    
In summary , the results from this meta- analysis do not favor any clinical efficacy  of blueberry supplementation in improving BP .