***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: BACKGROUND Although numerous human studies have shown consistent effects of some polyphenol-rich foods on several intermediate markers for cardiovascular diseases , it is still unknown whether their action could be specifically related to polyphenols . OBJECTIVE We investigated the effect of orange juice and its major flavonoid , hesperidin , on microvascular reactivity , blood pressure , and cardiovascular risk biomarkers through both postpr and ial and chronic intervention studies . DESIGN Twenty-four healthy , overweight men ( age 50 - 65 y ) were included in a r and omized , controlled , crossover study . Throughout the three 4-wk periods , volunteers daily consumed 500 mL orange juice , 500 mL control drink plus hesperidin ( CDH ) , or 500 mL control drink plus placebo ( CDP ) . All measurements and blood collection s were performed in overnight-fasted subjects before and after the 4-wk treatment periods . The postpr and ial study was conducted at the beginning of each experimental period . RESULTS Diastolic blood pressure ( DBP ) was significantly lower after 4 wk consumption of orange juice or CDH than after consumption of CDP ( P = 0.02 ) , whereas microvascular endothelium-related reactivity was not significantly affected when measured after an overnight fast . However , both orange juice and CDH ingestion significantly improved postpr and ial microvascular endothelial reactivity compared with CDP ( P < 0.05 ) when measured at the peak of plasma hesperetin concentration . CONCLUSIONS In healthy , middle-aged , moderately overweight men , orange juice decreases DBP when regularly consumed and postpr and ially increases endothelium-dependent microvascular reactivity . Our study suggests that hesperidin could be causally linked to the beneficial effect of orange juice . This trial is registered at clinical trials.gov as NCT00983086 Pomegranate juice ( PJ ; also known as pomegreat pure juice ) provides a rich and varied source of polyphenolic compounds that may offer cardioprotective , anti-atherogenic and antihypertensive effects . The aim of this study was to investigate the effect of PJ consumption on glucocorticoids levels , blood pressure ( BP ) and insulin resistance in volunteers at high CVD risk . Subjects ( twelve males and sixteen females ) participated in a r and omised , placebo-controlled cross-over study ( BMI : 26·77 ( sd 3·36 ) kg/m2 ; mean age : 50·4 ( sd 6·1 ) years ) . Volunteers were assessed at baseline , and at weeks 2 and 4 for anthropometry , BP and pulse wave velocity . Cortisol and cortisone levels in urine and saliva were determined by specific ELISA methods , and the cortisol/cortisone ratio was calculated . Fasting blood sample s were obtained to assess plasma lipids , glucose , insulin and insulin resistance ( homeostasis model assessment of insulin resistance ) . Volunteers consumed 500 ml of PJ or 500 ml of a placebo drink containing a similar amount of energy . Cortisol urinary output was reduced but not significant . However , cortisol/cortisone ratios in urine ( P = 0·009 ) and saliva ( P = 0·024 ) were significantly decreased . Systolic BP decreased from 136·4 ( sd 6·3 ) to 128·9 ( sd 5·1 ) mmHg ( P = 0·034 ) , and diastolic BP from 80·3 ( sd 4·29 ) to 75·5 ( sd 5·17 ) mmHg ( P = 0·031 ) after 4 weeks of fruit juice consumption . Pulse wave velocity decreased from 7·5 ( sd 0·86 ) to 7·44 ( sd 0·94 ) m/s ( P = 0·035 ) . There was also a significant reduction in fasting plasma insulin from 9·36 ( sd 5·8 ) to 7·53 ( sd 4·12 ) mIU/l ( P = 0·025 ) and of homeostasis model assessment of insulin resistance ( from 2·216 ( sd 1·43 ) to 1·82 ( sd 1·12 ) , P = 0·028 ) . No significant changes were seen in the placebo arm of the study . These results suggest that PJ consumption can alleviate key cardiovascular risk factors in overweight and obese subjects that might be due to a reduction in both systolic and diastolic BP , possibly through the inhibition of 11β-hydroxysteroid dehydrogenase type 1 enzyme activity as evidence d by the reduction in the cortisol/cortisone ratio . The reduction in insulin resistance might have therapeutic benefits for patients with non-insulin-dependent diabetes , obesity and the metabolic syndrome Background : Type 2 diabetic patients are faced with a higher risk of dyslipidemia and cardiovascular disorders . This study was undertaken to assess the effect of consumption of 1 cup cranberry juice by type 2 diabetic patients on serum paraoxonase-1 ( PON-1 ) activity , apoA-1 , apoB , glucose , and Lp(a ) . Methods : In a double-blind r and omized clinical trial , 58 type 2 diabetic male patients were r and omly divided to receive 1 cup cranberry juice ( CJ ) or placebo drink daily for 12 weeks . Fasting blood were obtained at beginning and at the end of study ( 12th week ) . Serum glucose and PON-1 activity were measured by enzymatic and colorimetric methods , respectively . ApoB , apoA-I , and Lp(a ) were determined immunoturbidimetrically . The data were analyzed by SPSS version 16 . Results : There were significant decrease in serum glucose and apoB ( P>0.05 and P>0.01 , respectively ) and significant increase in serum apoA-1 and PON-1 activity ( P>0.05 and P<0.01 , respectively ) at the end of study in CJ group compared with control group . In CJ group at the end of study , there were significant decrease in serum glucose and apoB ( P<0.01 and P<0.01 , respectively ) and significant increase in serum apo A-1 and PON-1 activity ( P<0.01 and P<0.01 , respectively ) compared with initial values . In CJ group , there was no significant change in Lp(a ) at the end of study compared with initial values and also compared with control group . Conclusion : 1 cup CJ for 12 weeks is effective in reducing serum glucose and apoB and increasing apoA-1 and PON-1 activity , so may have favorite effects on reducing CVD risk factors in type 2 diabetic male patients Intake of fruits and berries may lower blood pressure ( BP ) , most probably due to the high content of polyphenols . In the present study , we tested whether consumption of two polyphenol-rich juices could lower BP . In a r and omised , double-blinded , placebo-controlled trial of 12 weeks , 134 healthy individuals , aged 50 - 70 years , with high normal range BP ( 130/85 - 139/89 mmHg , seventy-two subjects ) or stage 1 - 2 hypertension ( 140/90 - 179/109 mmHg , sixty-two subjects ) , were included . They consumed 500 ml/d of one of either ( 1 ) a commercially available polyphenol-rich juice based on red grapes , cherries , chokeberries and bilberries ; ( 2 ) a juice similar to ( 1 ) but enriched with polyphenol-rich extracts from blackcurrant press-residue or ( 3 ) a placebo juice ( polyphenol contents 245·5 , 305·2 and 76 mg/100 g , respectively ) . Resting BP was measured three times , with a 1 min interval , at baseline and after 6 and 12 weeks of intervention . Systolic BP significantly reduced over time ( 6 and 12 weeks , respectively ) in the pooled juice group compared with the placebo group in the first of the three measurements , both for the whole study group ( 6·9 and 3·4 mmHg ; P= 0·01 ) and even more pronounced in the hypertensive subjects when analysed separately ( 7·3 and 6·8 mmHg ; P= 0·04 ) . The variation in the BP measurements was significantly reduced in the pooled juice group compared with the placebo group ( 1·4 and 1·7 mmHg ; P= 0·03 ) . In conclusion , the present findings suggest that polyphenol-rich berry juice may contribute to a BP- and BP variability lowering effect , being more pronounced in hypertensive than in normotensive subjects Introduction Diabetes mellitus characterized by hyperglycemia could increase oxidative stress and formation of advanced glycated end-products ( AGEs ) , which contribute to diabetic complications . The purpose of this study was to assess the effect of pomegranate juice ( PJ ) containing natural antioxidant on lipid peroxidation and plasma AGEs in patients with type 2 diabetes ( T2D ) . Material s and methods In a r and omized , double-blind , placebo-controlled trial , 44 patients ( age range 56±6.8 years ) , T2D were r and omly assigned to one of two groups : group A ( PJ , n=22 ) and group B ( Placebo , n=22 ) . At the baseline and the end of 12-week intervention ,  biochemical markers including fasting plasma glucose , insulin , oxidative stress , and AGE markers including carboxy methyl lysine ( CML ) and pentosidine  were assayed . Results At baseline , there were no significant differences in plasma total antioxidant capacity ( TAC ) levels between the two groups , but malondialdehyde ( MDA ) decreased levels were significantly different ( P<0.001 ) . After 12 weeks of intervention , TAC increased ( P<0.05 ) and MDA decreased ( P<0.01 ) in the PJ group when compared with the placebo group . However , no significant differences were observed in plasma concentration of CML and pentosidine between the two groups . Conclusions The study showed that PJ decreases lipid peroxidation . Therefore , PJ consumption may delay onset of T2D complications related to oxidative stress BACKGROUND The consumption of citrus fruits is associated with health benefits . However , clinical data regarding the effects of grapefruit flavanone consumption on vascular function are lacking . OBJECTIVE The objective of the present study was to address the role of flavanones in the long-term effects induced by grapefruit juice ( GFJ ) consumption on vascular function in healthy postmenopausal women . DESIGN Forty-eight healthy postmenopausal women aged 50 - 65 y within 3 - 10 y since menopause , a body mass index ( in kg/m(2 ) ) of 19 - 30 , and a waist size > 88 cm completed this double-blind , r and omized , controlled , crossover trial . These volunteers were r and omly assigned to consume 340 mL GFJ/d , providing 210 mg naringenin glycosides , or a matched control drink without flavanones for 6 mo each , with a 2-mo washout between beverages . The primary endpoint was the assessment of endothelial function in the brachial artery by using flow-mediated dilation . Blood pressure , arterial stiffness , and endothelial function in the peripheral arterial bed were also evaluated as indicators of vascular function . These measurements and blood collection for clinical biochemical markers were performed in overnight-fasted subjects before and after the 6-mo treatment periods . RESULTS The mean ± SD carotid-femoral pulse wave velocity , which reflects central aortic stiffness , was statistically significantly lower after consumption of GFJ ( 7.36 ± 1.15 m/s ) than after consumption of the matched control drink without flavanones ( 7.70 ± 1.36 m/s ) , with a P value of 0.019 for the treatment effect . Endothelial function in macro- and microcirculation , blood pressure , anthropometric measures , glucose metabolism , and biomarkers of inflammation and oxidative stress were not affected by the intervention . CONCLUSIONS Regular GFJ consumption by middle-aged , healthy postmenopausal women is beneficial for arterial stiffness . This effect may be related to flavanones present in grapefruit . This trial was registered at clinical trials.gov as NCT01272167 Objective : The aim of the present study is to investigate the effect of antioxidant polyphenol-rich pomegranate juice ( PJ ) supplementation for 5 weeks on patients with stable chronic obstructive pulmonary disease ( COPD ) , since the oxidative stress plays a major role in the evolution and pathophysiology of COPD . Design : A r and omized , double-blind , placebo-controlled trial was conducted . Subjects : A total of 30 patients with stable COPD were r and omly distributed in two groups ( 15 patients each ) . Interventions : Both groups consumed either 400 ml PJ daily or matched placebo ( synthetic orange-flavoured drink ) for 5 weeks . Trolox Equivalent Antioxidant Capacity ( TEAC ) of PJ , blood parameters ( 14 haematological and 18 serobiochemical ) , respiratory function variables , bioavailability of PJ polyphenols ( plasma and ur 
    Output:
    
Results from stratified analyses and univariate meta-regressions also largely showed no significant associations between 100 % fruit juice and the measures of glucose control .
Overall , findings from this meta- analysis of RCT suggest a neutral effect of 100 % fruit juice on glycaemic control .
These findings are consistent with findings from some observational studies suggesting that consumption of 100 % fruit juice is not associated with increased risk of diabetes