***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: Data derived from laboratory investigations suggest that a number of dietary variables may contribute to bladder carcinogenesis . Although bladder cancer is the fourth leading cause of cancer in men in the United States , dietary studies are few . The authors examined the relations between intakes of macro- and micronutrients and the  risk of bladder cancer among men in the prospect i ve Health Professionals Follow-Up Study . Each participant completed a 131-item food frequency question naire in 1986 and in 1990 , from which nutrient intakes were calculated . During 12 years of follow-up , 320 cases of bladder cancer were diagnosed . No association was observed for total caloric or macronutrient intake and bladder cancer risk . Similarly , we found no relation for dietary intake of potassium , sodium , calcium , magnesium , phosphorus , iron , or water-soluble vitamins and bladder cancer risk . Total vitamin E intake and vitamin E supplements  were inversely associated with risk . In addition , a dose-response relation was observed for duration of vitamin E supplement use . A suggestive inverse association was seen with dose of vitamin C supplement use . More studies are needed to determine the role of vitamins E and C supplement intake in bladder carcinogenesis We examined the relation between dietary fruit and vegetables , carotenoids and vitamin intakes and the  risk of bladder cancer among male smokers in a prospect i ve cohort study . Over a median of 11 years , we followed 27 111 male smokers aged 50–69 years who were initially enrolled in the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study . During this period , 344 men developed bladder cancer . All of these men had completed a 276-food item dietary question naire at baseline . Cox proportional hazards models were used to estimate the relative risks and 95 % confidence intervals and to simultaneously adjust for age , smoking history , energy intake and intervention group . Consumption of fruits and vegetables was not associated with the risk of bladder cancer ( relative risk=1.28 ; 95 % confidence intervals CI : 0.89–1.84 , for highest vs lowest quintile ) . Similarly , no associations were observed for groups of fruits or vegetables ( berries and cruciferous vegetables ) , or for specific fruits and vegetables . Dietary intakes of alpha-carotene , beta-carotene , lycopene , lutein/zeaxanthin , beta-cryptoxanthin , vitamins A , E , and C , and folate were not related to the risk of bladder cancer . These findings suggest that fruit and vegetable intakes are not likely to be associated with bladder cancer risk . However , these results may not be generalisable to non-smokers BACKGROUND There is probable evidence that some types of fruit and vegetables provide protection against many cancers . OBJECTIVE We hypothesized that fruit and vegetable intakes are inversely related to the incidence of total cancers among women and men aged > 50 y. DESIGN We performed a prospect i ve study among the cohort of the National Institutes of Health-AARP Diet and Health Study . We merged the MyPyramid Equivalents Data base ( version 1.0 ) with food-frequency- question naire data to calculate cup equivalents for fruit and vegetables .  From 1995 to 2003 , we identified 15,792 and 35,071 cancer cases in 195,229 women and 288,109 men , respectively . We used Cox proportional hazards models to estimate multivariate relative risks ( RRs ) and 95 % CIs associated with the highest compared with the lowest quintile ( Q ) of fruit and vegetable intakes . RESULTS Fruit intake was not associated with the risk of total cancer among women ( RR(Q5 vs Q1 ) = 0.99 ; 95 % CI : 0.94 , 1.05 ; P trend = 0.059 ) or men ( RR(Q5 vs Q1 ) = 0.98 ; 95 % CI : 0.95 , 1.02 ; P for trend = 0.17 ) . Vegetable intake was not associated with risk of total cancer among women ( RR(Q5 vs Q1 ) = 1.04 ; 95 % CI : 0.98 , 1.09 ; P for trend = 0.084 ) , but was associated with a significant decrease in risk in men ( RR(Q5 vs Q1 ) = 0.94 ; 95 % CI : 0.91 , 0.97 ; P trend = 0.004 ) . This significant finding among men was no longer evident when we limited the analysis to men who never smoked ( RR(Q5 vs Q1 ) = 0.97 ; 95 % CI : 0.91 , 1.04 ; P for trend = 0.474 ) . CONCLUSIONS Intake of fruit and vegetables was generally unrelated to total cancer incidence in this cohort . Residual confounding by smoking is a likely explanation for the observed inverse association with vegetable intake among men BACKGROUND Previous epidemiologic studies of fruit and vegetable intake and bladder cancer risk have yielded inconsistent results , especially with regard to the types of fruits and vegetables consumed . We examined total fruit and vegetable intake  , as well as intakes of subtypes of fruits and vegetables , in relation to bladder cancer risk in a large male prospect i ve cohort study . METHODS Two hundred fifty-two cases of incident bladder cancer were diagnosed from 1986 through January 31 , 1996 , among 47,909 men enrolled in the Health Professionals Follow-up Study . Each participant in this cohort completed a 131-item food-frequency question naire in 1986 and subsequently in 1990 and 1994 . We used logistic regression analyses to examine  fruit and vegetable intake in relation to bladder cancer risk , after adjusting for age , history of cigarette smoking , current smoking status , geographic region , total fluid intake , and caloric intake . RESULTS We observed a weak , inverse association that was not statistically significant between total fruit and vegetable intake and bladder cancer risk . Intake of cruciferous vegetables was inversely associated with risk ( relative risk = 0.49 ; 95 % confidence interval = 0.32 - 0.75 , for the highest category of cruciferous vegetable intake compared with the lowest ) , but intakes of yellow or green leafy vegetables or carotenoid-rich vegetables were not associated with risk . Individual cruciferous vegetables , except for coleslaw , were all inversely related to bladder cancer risk , but only the associations for broccoli and cabbage were statistically significant . CONCLUSIONS Data from this study indicate that high cruciferous vegetable consumption may reduce bladder cancer risk , but other vegetables and fruits may not confer appreciable benefits against this cancer CONTEXT Previous studies indicate that the population attributable risk ( PAR ) of bladder cancer for tobacco smoking is 50 % to 65 % in men and 20 % to 30 % in women and that current cigarette smoking triples bladder cancer risk relative to never smoking . During the last 30 years , incidence rates have remained stable in the United States in men ( 123.8 per 100,000 person-years to 142.2 per 100,000 person-years ) and women ( 32.5 per 100,000 person-years to 33.2 per 100,000 person-years ) ; however , changing smoking prevalence and cigarette composition warrant revisiting risk estimates for smoking and bladder cancer . OBJECTIVE To evaluate the association between tobacco smoking and bladder cancer . DESIGN , SETTING , AND PARTICIPANTS Men ( n = 281,394 ) and women ( n = 186,134 ) of the National Institutes of Health-AARP ( NIH-AARP ) Diet and Health Study cohort completed a lifestyle question naire  and were followed up between October 25 , 1995 , and December 31 , 2006 . Previous prospect i ve cohort studies of smoking and incident bladder cancer were identified by systematic review and relative risks were estimated from fixed-effects models with heterogeneity assessed by the I(2 ) statistic . MAIN OUTCOME MEASURES Hazard ratios ( HRs ) , PARs , and number needed to harm ( NNH ) . RESULTS During 4,518,941 person-years of follow-up , incident bladder cancer occurred in 3896 men ( 144.0 per 100,000 person-years ) and 627 women ( 34.5 per 100,000 person-years ) . Former smokers ( 119.8 per 100,000 person-years ; HR , 2.22 ; 95 % confidence interval [ CI ] , 2.03 - 2.44 ; NNH , 1250 ) and current smokers ( 177.3 per 100,000 person-years ; HR , 4.06 ; 95 % CI , 3.66 - 4.50 ; NNH , 727 ) had higher risks of bladder cancer than never smokers ( 39.8 per 100,000 person-years ) . In contrast , the summary risk estimate for current smoking in 7 previous studies ( initiated between 1963 and 1987 ) was 2.94 ( 95 % CI , 2.45 - 3.54 ; I(2 ) = 0.0 % ) . The PAR for ever smoking in our study was 0.50 ( 95 % CI , 0.45 - 0.54 ) in men and 0.52 ( 95 % CI , 0.45 - 0.59 ) in women . CONCLUSION Compared with a pooled estimate of US data from cohorts initiated between 1963 and 1987 , relative risks for smoking in the more recent NIH-AARP Diet and Health Study cohort were higher , with PARs for women comparable with those for men Objective : To examine the relation between fruits and vegetables , carotenoids , folate , and vitamins A , C , E and the  risk of bladder cancer  in a prospect i ve study of women Methods : A total of 237 incident bladder cancer cases were documented during 20 years of follow-up among 88,796 women enrolled in the Nurses ’ Health Study . Dietary intake was assessed by food-frequency question naires every two to four years and incident diagnosis of bladder cancer was ascertained every two years . Cox proportional hazard models were used to estimate incidence rate ratios ( RR ) and 95 % confidence intervals ( CI ) for bladder cancer risk , adjusting for age , pack-years of smoking , current smoking , and total caloric intake . Results : Consumption of total fruits and vegetables was not associated with bladder cancer risk ( RR = 1.08 , 95 % CI = 0.70–1.65 , for > 5.5 compared to < 2.5 servings per day ) . Similarly , dietary intakes of carotenoids , folate , and vitamins A , C , E , were not related to bladder cancer risk . No association was observed between supplemental intake of multivitamins , vitamins A , C , E and bladder cancer risk . Conclusions : We did not observe any association for fruit and vegetable consumption or vitamin intake and bladder cancer risk among women Fruit and vegetable consumption has been inconsistently associated with risk of bladder cancer . We used data from a prospect i ve population -based cohort study of 82,002 Swedish women and men to examine the association between fruit and vegetable consumption  and bladder cancer incidence . Diet was assessed with a vali date d food frequency question naire . During a mean follow-up of 9.4 years , 485 incident cases of bladder cancer were identified in the Swedish cancer registries . We found no statistically significant association between intakes of total fruits and vegetables , total fruits , or total vegetables and bladder cancer risk after adjustment for age , sex , education , and cigarette smoking . The multivariate rate ratios ( 95 % confidence intervals ) comparing the highest with the lowest quartile of intake were 0.80 ( 0.60 - 1.05 ) for total fruits and vegetables , 0.93 ( 0.69 - 1.25 ) for fruits , and 0.89 ( 0.67 - 1.19 ) for vegetables . Likewise , no associations were observed for citrus fruits , cruciferous vegetables , or green leafy vegetables .  The associations did not differ by sex or smoking status . In conclusion , findings from this prospect i ve study suggest that fruit and vegetable intakes are not likely to be appreciably associated with the risk of bladder cancer . ( Cancer Epidemiol Biomarkers Prev 2008;17(9):2519–22 BACKGROUND Published associations between dietary carotenoids and vitamin C and bladder cancer risk are inconsistent . Biomarkers may provide more accurate measures of nutrient status . OBJECTIVE We investigated the association between plasma carotenoids and vitamin C  and risk of urothelial cell carcinoma ( UCC )  in a case-control study nested within the European Prospect i ve Investigation into Cancer and Nutrition . DESIGN A total of 856 patients with newly diagnosed UCC were matched with 856 cohort members by sex , age at baseline , study center , date and time of 
    Output:
    
The current evidence from cohort studies is not consistent with a role for fruits and vegetables in preventing bladder cancer