Fruit and vegetable consumption and lung cancer risk: updated information from the European Prospective Investigation into Cancer and Nutrition (EPIC)

The association of fruit and vegetable consumption and lung cancer incidence was evaluated using the most recent data from the European Prospective Investigation into Cancer and Nutrition (EPIC), applying a refined statistical approach (calibration) to account for measurement error potentially introduced by using food frequency questionnaire data. Between 1992 and 2000, detailed information on diet and life-style of 478,590 individuals participating in EPIC was collected. During a median follow-up of 6.4 years, 1,126 lung cancer cases were observed. Multivariate Cox proportional hazard models were applied for statistical evaluation. In the whole study population, fruit consumption was significantly inversely associated with lung cancer risk while no association was found for vegetable consumption. In current smokers, however, lung cancer risk significantly decreased with higher vegetable consumption; this association became more pronounced after calibration, the hazard ratio (HR) being 0.78 (95% CI 0.62-0.98) per 100 g increase in daily vegetable consumption. In comparison, the HR per 100 g fruit was 0.92 (0.85-0.99) in the entire cohort and 0.90 (0.81-0.99) in smokers. Exclusion of cases diagnosed during the first 2 years of follow-up strengthened these associations, the HR being 0.71 (0.55-0.94) for vegetables (smokers) and 0.86 (0.78-0.95) for fruit (entire cohort). Cancer incidence decreased with higher consumption of apples and pears (entire cohort) as well as root vegetables (smokers). In addition to an overall inverse association with fruit intake, the results of this evaluation add evidence for a significant inverse association of vegetable consumption and lung cancer incidence in smokers.     

Variety in vegetable and fruit consumption and risk of bladder cancer in the European Prospective Investigation into Cancer and Nutrition

Recent research does not show an association between fruit and vegetable consumption and bladder cancer risk. None of these studies investigated variety in fruit and vegetable consumption, which may capture different aspects of consumption. We investigated whether a varied consumption of vegetables and fruits is associated with bladder cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Detailed data on food consumption and complete follow-up for cancer incidence were available for 452,185 participants, who were recruited from ten European countries. After a mean follow-up of 8.7 years, 874 participants were diagnosed with bladder cancer. Diet diversity scores (DDSs) were used to quantify the variety in fruit and vegetable consumption. Multivariable Cox proportional hazard models were used to assess the effect of the DDSs on bladder cancer risk. There was no evidence of a statistically significant association between bladder cancer risk and any of the DDSs when these scores were considered as continuous covariates. However, the hazard ratio (HR) for the highest tertile of the DDS for combined fruit and vegetable consumption was marginally significant compared to the lowest (HR = 1.30, 95% confidence interval: 1.00-1.69, p-trend = 0.05). In EPIC, there is no clear association between a varied fruit and vegetable consumption and bladder cancer risk. This finding provides further evidence for the absence of any strong association between fruit and vegetable consumption as measured by a food frequency questionnaire and bladder cancer risk.     

Cohort analysis of fruit and vegetable consumption and lung cancer mortality in European men

Our aim was to examine the relationship between fruit and vegetable consumption and lung cancer mortality in a cohort of European males. Around 1970, dietary intake of Finnish, Italian and Dutch middle-aged men was assessed using a cross-check dietary history. Complete baseline information was available for 3,108 men, of whom 1,578 were baseline smokers. We used Cox proportional hazard analyses to calculate risk estimates for the consumption in country-specific tertiles on lung cancer in smokers. During 25 years of follow-up, 149 lung cancer deaths occurred in the smokers. Fruit consumption was inversely associated with lung cancer mortality among smokers; compared with the lowest, adjusted RRs for the intermediate and highest tertiles were 0.56 (0.37-0.84) and 0.69 (0.46-1.02), p-trend 0.05. Only in the Dutch cohort was this association statistically significant [adjusted relative risks (RRs) 1.00, 0.33 (0.16-0.70) and 0.35 (0.16-0.74), p-trend 0.004]. In Finland lung cancer risk was lower with higher fruit intake but not significantly, whereas in Italy no association was observed. Stratifying on cigarette smoking intensity (non, light and heavy) revealed an inverse association in the heavy smokers only [adjusted RRs (95% confidence intervals [CI]) 1; 0.47 (0.26-0.84); 0.40 (0.20-0.78)). Vegetable consumption was not related to lung cancer risk in smokers. However, analyses stratified on cigarette smoking intensity gave some indication for a lower lung cancer risk with higher intake. In conclusion, in this prospective analysis among European smoking men, fruit intake was inversely related to lung cancer mortality. This association was confined to heavy cigarette smokers.     

Risk of lung cancer and consumption of vegetables and fruit in Japanese: A pooled analysis of cohort studies in Japan

International reviews have concluded that consumption of fruit and vegetables might decrease the risk of lung cancer. However, the relevant epidemiological evidence still remains insufficient in Japan. Therefore, we performed a pooled analysis of data from four population‐based cohort studies in Japan with >200 000 participants and >1700 lung cancer cases. We computed study‐specific hazard ratios by quintiles of vegetable and fruit consumption as assessed by food frequency questionnaires. Summary hazard ratios were estimated by pooling the study‐specific hazard ratios with a fixed‐effect model. In men, we found inverse associations between fruit consumption and the age‐adjusted and area‐adjusted risk of mortality or incidence of lung cancer. However, the associations were largely attenuated after adjustment for smoking and energy intake. The significant decrease in risk among men remained only for a moderate level of fruit consumption; the lowest summary hazard ratios were found in the third quintile of intake (mortality: 0.71, 95% confidence interval 0.60–0.84; incidence: 0.83, 95% confidence interval 0.70–0.98). This decrease in risk was mainly detected in ever smokers. Conversely, vegetable intake was positively correlated with the risk of incidence of lung cancer after adjustment for smoking and energy intake in men (trend P, 0.024); the summary hazard ratio for the highest quintile was 1.26 (95% confidence interval 1.05–1.50). However, a similar association was not detected for mortality from lung cancer. In conclusion, a moderate level of fruit consumption is associated with a decreased risk of lung cancer in men among the Japanese population.     

Fruits and vegetables and renal cell carcinoma: findings from the European prospective investigation into cancer and nutrition (EPIC)

We examined the association between fruits and vegetables and risk of renal cell carcinoma (RCC) in the European Prospective Investigation into Cancer and Nutrition (EPIC). Dietary intake data and complete follow-up information on cancer incidence were available for 375,851 participants recruited in EPIC centers of 8 countries. During an average follow-up of 6.2 years, 306 incident cases of RCC were identified. The associations of consumption of total vegetables, total fruits, combined total fruits and vegetables and specific subtypes of vegetables with RCC risk were analyzed using Cox proportional hazards, stratified by centre and adjusted for potential confounders. No significant associations between fruit and vegetable consumption and RCC risk were observed despite a wide range of intake. The estimated relative risks (95% confidence intervals [CI]) in men and women combined were 0.97 (0.85-1.11) per 40 g increase in vegetable intake, 1.03 (0.97-1.08) per 40 g increase in fruit intake and 1.02 (0.93-1.11) per 80 g increase in fruit and vegetable intake combined. Among the vegetable subtypes, an inverse association was observed for root vegetables (RR per 8 g increase: 0.88; 95% CI: 0.78-0.99). These results suggest that total consumption of fruits and vegetables is not related to risk of RCC, although we cannot exclude the possibility that very low consumption is related to higher risk. The relationship of specific fruit and vegetable subgroups with RCC risk warrant further investigation.     

Intake of vegetables, fruits, carotenoids and vitamins C and E and pancreatic cancer risk in The Netherlands Cohort Study

Epidemiological data investigating the relation between fruit and vegetable consumption and pancreatic cancer risk have shown inconsistent results so far. Most case-control studies observed an inverse association with total fruit and vegetable consumption, whereas results from most cohort studies have largely been null. We examined prospectively the relation between pancreatic cancer risk and intake of vegetables, fruits, carotenoids and vitamins C and E. The Netherlands Cohort Study consisted of 120,852 men and women who completed a questionnaire at baseline in 1986, including a validated 150-item food-frequency questionnaire. After 16.3 years of follow-up, 423 cases were available for analysis. Total vegetable and total fruit consumption were not associated with pancreatic cancer risk (highest vs. lowest quintile, multivariable-adjusted hazard rate ratio = 1.23, 95% confidence interval: 0.86-1.75 and multivariable-adjusted hazard rate ratio = 0.90, 95% confidence interval: 0.66-1.24, respectively). Also, for cooked vegetables, raw vegetables and vegetables and fruits classified into subgroups, no associations were observed. Dietary carotenoids, vitamin C and E intake and supplements containing vitamin C or E were not associated with pancreatic cancer risk. The results were not modified by sex, smoking status and body mass index. In conclusion, we observed no association between a high consumption of vegetables and fruits and pancreatic cancer risk in this large cohort study, which is in agreement with previous prospective studies. Furthermore, we observed no association between the intake of carotenoids, vitamins and vitamin supplements and pancreatic cancer risk.     

Prospective study of fruit and vegetable consumption and risk of lung cancer among men and women

BACKGROUND: Diets high in fruits and vegetables have been shown to be associated with a lower risk of lung cancer. beta-Carotene was hypothesized to be largely responsible for the apparent protective effect, but this hypothesis was not supported by clinical trials. METHODS: We examined the association between lung cancer risk and fruit and vegetable consumption in 77 283 women in the Nurses' Health Study and 47 778 men in the Health Professionals' Follow-up Study. Diet was assessed with the use of a food-frequency questionnaire that included 15 fruits and 23 vegetables. We used logistic regression models to estimate relative risks (RRs) of lung cancer within each cohort. All statistical tests were two-sided. RESULTS: We documented 519 lung cancer cases among the women and 274 among the men. Total fruit and vegetable consumption was associated with a modestly lower risk of lung cancer among the women but not among the men. The RR for the highest versus lowest quintile of intake was 0.79 (95% confidence interval [CI] = 0.59-1.06) among the women and 1.12 (95% CI = 0.74-1.69) among the men after adjustment for smoking status, quantity of cigarettes smoked per day, time since quitting smoking, and age at initiation of smoking. However, total fruit and vegetable consumption was associated with a lower risk of lung cancer among never smokers in the combined cohorts, although the reduction was not statistically significant (RR = 0.63; 95% CI = 0.35-1.12 in the highest tertile). CONCLUSION: Higher fruit and vegetable intakes were associated with lower risks of lung cancer in women but not in men. It is possible that the inverse association among the women remained confounded by unmeasured smoking characteristics, although fruits and vegetables were protective in both men and women who never smoked.     

Vegetables, Fruit Consumption and Risk of Lung Cancer among Middle-Aged Japanese Men and Women: JPHC Study

OBJECTIVE: To investigate the association between vegetable and fruit consumption and incidence of lung cancer. METHODS: Self-administered questionnaires were used to assess diet in two large population-based cohorts with 42,224 and 51,114 subjects in 1990 and 1993, respectively. After ten and seven years of follow-up, we ascertained 428 newly diagnosed case of lung cancer. Relative risk (RR) estimates were calculated using the Cox proportional hazards model with pooling of estimates from the two cohorts. RESULTS: Total vegetable and fruit intake was not associated with lowered risk of lung cancer, with RR approximating unity. The null relation between vegetable and fruit consumption and lung cancer incidence was consistent across strata of smoking status (never or ever smokers). When dividing lung cancers into adenocarcinoma and non-adenocarcinoma, risk for middle and high intakes of vegetables only, fruit only, and vegetables and fruit combined were all below one for non-adenocarcinoma and above one for adenocarcinoma, although no statistically significant differences were noted. Similar patterns of results were found when the two cohorts were analyzed separately. CONCLUSIONS: Contrary to popular belief, our results suggest that vegetables and fruit do not appear to confer protection from lung cancer.     

Smoking and the risk of gastric cancer in the European Prospective Investigation Into Cancer and Nutrition (EPIC)

Smoking has recently been recognised as causally associated with the development of gastric cancer (GC). However, evidence on the effect by sex, duration and intensity of smoking, anatomic subsite and cessation of smoking is limited. Our objective was to assess the relation between tobacco use and GC incidence in the European Prospective Investigation into Cancer and Nutrition (EPIC). We studied data from 521,468 individuals recruited from 10 European countries taking part in the EPIC study. Participants completed lifestyle questionnaires that included questions on lifetime consumption of tobacco and diet in 1991-1998. Participants were followed until September 2002, and during that period 305 cases of stomach cancer were identified. After exclusions, 274 were eligible for the analysis, using the Cox proportional hazard model. After adjustment for educational level, consumption of fresh fruit, vegetables and preserved meat, alcohol intake and body mass index (BMI), there was a significant association between cigarette smoking and gastric cancer risk: the hazard ratio (HR) for ever smokers was 1.45 (95% confidence interval [CI] = 1.08-1.94). The HR of current cigarette smoking was 1.73 (95% CI = 1.06-2.83) in males and 1.87 (95% CI = 1.12-3.12) in females. Hazard ratios increased with intensity and duration of cigarette smoked. A significant decrease of risk was observed after 10 years of quitting smoking. A preliminary analysis of 121 cases with identified anatomic site showed that current cigarette smokers had a higher HR of GC in the cardia (HR = 4.10) than in the distal part of the stomach (HR = 1.94). In this cohort, 17.6 % (95% CI = 10.5-29.5 %) of GC cases may be attributable to smoking. Findings from this large study support the causal relation between smoking and gastric cancer in this European population. Stomach cancer should be added to the burden of diseases caused by smoking.     

Fruit and vegetables and cancer risk

The possibility that fruit and vegetables may help to reduce the risk of cancer has been studied for over 30 years, but no protective effects have been firmly established. For cancers of the upper gastrointestinal tract, epidemiological studies have generally observed that people with a relatively high intake of fruit and vegetables have a moderately reduced risk, but these observations must be interpreted cautiously because of potential confounding by smoking and alcohol. For lung cancer, recent large prospective analyses with detailed adjustment for smoking have not shown a convincing association between fruit and vegetable intake and reduced risk. For other common cancers, including colorectal, breast and prostate cancer, epidemiological studies suggest little or no association between total fruit and vegetable consumption and risk. It is still possible that there are benefits to be identified: there could be benefits in populations with low average intakes of fruit and vegetables, such that those eating moderate amounts have a lower cancer risk than those eating very low amounts, and there could also be effects of particular nutrients in certain fruits and vegetables, as fruit and vegetables have very varied composition. Nutritional principles indicate that healthy diets should include at least moderate amounts of fruit and vegetables, but the available data suggest that general increases in fruit and vegetable intake would not have much effect on cancer rates, at least in well-nourished populations. Current advice in relation to diet and cancer should include the recommendation to consume adequate amounts of fruit and vegetables, but should put most emphasis on the well-established adverse effects of obesity and high alcohol intakes.     

A prospective analysis of the association between dietary fiber intake and prostate cancer risk in EPIC

Few studies have examined the association between dietary fiber intake and prostate cancer risk. We evaluated the association between dietary fiber intake and the risk of prostate cancer among 142,590 men in the European Prospective Investigation into Cancer and Nutrition (EPIC). Consumption of dietary fiber (total, cereal, fruit and vegetable fiber) was estimated by validated dietary questionnaires and calibrated using 24-hr dietary recalls. Incidence rate ratios were estimated using Cox regression and adjusted for potential confounding factors. During an average of 8.7 years follow-up, prostate cancer was diagnosed in 2,747 men. Overall, there was no association between dietary fiber intake (total, cereal, fruit or vegetable fiber) and prostate cancer risk, although calibrated intakes of total fiber and fruit fiber were associated with nonstatistically significant reductions in risk. There was no association between fiber derived from cereals or vegetables and risk and no evidence for heterogeneity in any of the risk estimates by stage or grade of disease. Our results suggest that dietary fiber intake is not associated with prostate cancer risk.     

Fruit and vegetable consumption and risk of aggressive and non-aggressive urothelial cell carcinomas in the European Prospective Investigation into Cancer and Nutrition

BackgroundMany epidemiological studies have examined fruit and vegetable consumption in relation to the risk of urothelial cell carcinoma (UCC) of the bladder, but results are inconsistent. The association between fruit and vegetable consumption and UCC risk may vary by bladder tumour aggressiveness. Therefore, we examined the relation between fruit and vegetable consumption and the risk of aggressive and non-aggressive UCC in the European Prospective Investigation into Cancer and Nutrition (EPIC).MethodsAfter 8.9 years of follow-up, 947 UCC were diagnosed among 468,656 EPIC participants. Of these, 421 could be classified as aggressive UCC and 433 as non-aggressive UCC cases. At recruitment, fruit and vegetable consumption was assessed by validated dietary questionnaires. Multivariable hazard ratios were estimated using Cox regression stratified by age, sex and center and adjusted for smoking status, duration and intensity of smoking, and energy intake.ResultsTotal consumption of fruits and vegetables was not associated with aggressive UCC nor with non-aggressive UCC. A 25 g/day increase in leafy vegetables and grapes consumption was associated with a reduced risk of non-aggressive UCC (hazard ratio (HR) 0.88; 95% confidence interval (CI) 0.78–1.00 and HR 0.87; 95% CI 0.77–0.98, respectively), while the intake of root vegetables was inversely associated with risk of aggressive UCC (HR 0.87; 95% CI 0.77–0.98).ConclusionOur study did not confirm a protective effect of total fruit and/or vegetable consumption on aggressive or non-aggressive UCC. High consumption of certain types of vegetables and of fruits may reduce the risk of aggressive or non-aggressive UCC; however chance findings cannot be excluded.     

Fruit and vegetable intake and pancreatic cancer risk in a population-based cohort study in Japan

Oxidative stress and chronic inflammation are potential pathogenic factors of pancreatic cancer. Although fruits and vegetables are abundant in antioxidants and anti-inflammatory constituents, the reported associations between fruit and vegetable intake and pancreatic cancer risk have been inconsistent. Here, we investigated the association between fruit and vegetable intake and pancreatic cancer risk as part of the Japan Public Health Center-based Prospective Study. The analysis included 90,185 participants who responded to a medical and lifestyle questionnaire during 1995–1998. Associations between fruit and vegetable intake and pancreatic cancer risk were evaluated with Cox proportional hazards models. Additional analyses were stratified by smoking status and body mass index. During follow-up (median duration, 16.9 years), 577 participants were diagnosed with pancreatic cancer. In multivariate-adjusted models, pancreatic cancer risk was inversely associated with total fruit intake (highest vs. lowest intake quartile; hazard ratio [HR]: 0.74, 95% confidence interval [CI]: 0.57–0.95, p-trend: 0.116) and positively associated with total vegetable intake (HR: 1.30, 95% CI: 1.01–1.66, p-trend: 0.151). For total fruit intake, the inverse association with pancreatic cancer risk was more apparent in never smokers (HR: 0.67, 95% CI: 0.47–0.97, p-trend: 0.034). For total vegetable intake, the positive association was statistically significant in ever smokers (HR: 1.49, 95% CI: 1.01–2.19, p-trend: 0.043) and statistically nonsignificant in never smokers. In summary, total fruit intake and total vegetable intake had inverse and positive associations, respectively, with pancreatic cancer risk. Vegetable intake may correlate with increased risk partly because of the influence of smoking on vegetable intake.     

Fruit and vegetable consumption and risk of bladder cancer: a prospective cohort study

Fruit and vegetable consumption has been inconsistently associated with risk of bladder cancer. We used data from a prospective 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 validated food frequency questionnaire. 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 prospective study suggest that fruit and vegetable intakes are not likely to be appreciably associated with the risk of bladder cancer.     

Fruits, vegetables and lung cancer: a pooled analysis of cohort studies

Inverse associations between fruit and vegetable consumption and lung cancer risk have been consistently reported. However, identifying the specific fruits and vegetables associated with lung cancer is difficult because the food groups and foods evaluated have varied across studies. We analyzed fruit and vegetable groups using standardized exposure and covariate definitions in 8 prospective studies. We combined study-specific relative risks (RRs) using a random effects model. In the pooled database, 3,206 incident lung cancer cases occurred among 430,281 women and men followed for up to 6-16 years across studies. Controlling for smoking habits and other lung cancer risk factors, a 16-23% reduction in lung cancer risk was observed for quintiles 2 through 5 vs. the lowest quintile of consumption for total fruits (RR = 0.77; 95% CI = 0.67-0.87 for quintile 5; p-value, test for trend < 0.001) and for total fruits and vegetables (RR = 0.79; 95% CI = 0.69-0.90; p-value, test for trend = 0.001). For the same comparison, the association was weaker for total vegetable consumption (RR = 0.88; 95% CI = 0.78-1.00; p-value, test for trend = 0.12). Associations were similar between never, past, and current smokers. These results suggest that elevated fruit and vegetable consumption is associated with a modest reduction in lung cancer risk, which is mostly attributable to fruit, not vegetable, intake. However, we cannot rule out the possibility that our results are due to residual confounding by smoking. The primary focus for reducing lung cancer incidence should continue to be smoking prevention and cessation.     

Fruits and vegetables and prostate cancer: no association among 1104 cases in a prospective study of 130544 men in the European Prospective Investigation into Cancer and Nutrition (EPIC)

We examined the association between self-reported consumption of fruits and vegetables and prostate cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC). Data on food consumption and complete follow-up for cancer incidence were available for 130544 men in 7 countries recruited into EPIC between 1993 and 1999. After an average of 4.8 years of follow-up, there were 1104 incident cases of prostate cancer. The associations of consumption of total fruits, total vegetables, cruciferous vegetables and combined total fruits and vegetables with prostate cancer risk were examined using Cox regression, stratified for recruitment center and adjusted for height, weight and energy intake. There was a wide range in consumption of fruits and vegetables: mean intakes (g/day) in the bottom and top fifths of the distribution, as estimated from 24-hr recalls in a subsample of participants, were 53.2 and 410.7 for fruits, 97.1 and 242.1 for vegetables and 169.0 and 633.7 for fruits and vegetables combined. No significant associations between fruit and vegetable consumption and prostate cancer risk were observed. Relative risks (95% confidence intervals) in the top fifth of the distribution of consumption, compared to the bottom fifth, were 1.06 (0.84-1.34) for total fruits, 1.00 (0.81-1.22) for total vegetables and 1.00 (0.79-1.26) for total fruits and vegetables combined; intake of cruciferous vegetables was not associated with risk. These results suggest that total consumption of fruits and vegetables is not associated with the risk for prostate cancer.     

Parity and age at first childbirth in relation to the risk of different breast cancer subgroups

Many case‐control studies have suggested that higher consumption of fruit and vegetables is associated with a lower risk of pancreatic cancer, whereas cohort studies do not support such an association. We examined the associations of the consumption of fruits and vegetables and their main subgroups with pancreatic cancer risk within the European Prospective Investigation into Cancer and Nutrition (EPIC). EPIC is comprised of over 520,000 subjects recruited from 10 European countries. The present study included 555 exocrine pancreatic cancer cases after an average follow‐up of 8.9 years. Estimates of risk were obtained by Cox proportional hazard models, stratified by age at recruitment, gender, and study center, and adjusted for total energy intake, weight, height, history of diabetes mellitus, and smoking status. Total consumption of fruit and vegetables, combined or separately, as well as subgroups of vegetables and fruits were unrelated to risk of pancreatic cancer. Hazard ratios (95% CI) for the highest versus the lowest quartile were 0.92 (0.68–1.25) for total fruit and vegetables combined, 0.99 (0.73–1.33) for total vegetables, and 1.02 (0.77–1.36) for total fruits. Stratification by gender or smoking status, restriction to microscopically verified cases, and exclusion of the first 2 years of follow‐up did not materially change the results. These results from a large European prospective cohort suggest that higher consumption of fruit and vegetables is not associated with decreased risk of pancreatic cancer. © 2008 Wiley‐Liss, Inc.     

Dietary consumption of antioxidant vitamins and subsequent lung cancer risk: The Japan Public Health Center‐based prospective study

While many epidemiological studies have studied the association between lung cancer risk and fruits and vegetable consumption (the major sources of antioxidant vitamins), only a few have investigated the direct association with antioxidants in consideration of cancer subtypes and smoking status. Here, we examined the association between consumption of antioxidant vitamins and lung cancer risk in one of the largest prospective cohort studies in Japan. We investigated the association of dietary antioxidant vitamins intake, namely retinol, vitamin C, vitamin E, α‐carotene, and β‐carotene and subsequent incidence of lung cancer among 38,207 men and 41,498 women in the Japan Public Health Center‐based prospective study. Cox proportional hazard regression was performed with adjustment for potential confounders and by strata of cancer subtypes and smoking status. Antioxidant and other dietary intakes were assessed using a food frequency questionnaire (FFQ). During 1,233,096 person‐years of follow‐up between 1995 and 2013, a total of 1,690 lung cancer cases were newly diagnosed. In a multivariate regression model, while higher retinol intake was positively associated with overall lung cancer risk in men (HR 1.26; 95% CI 1.05–1.51; p_trend = 0.003), the estimates were more evident with small cell carcinoma (HR 1.92; 95% CI 1.13–3.24; p_trend < 0.001). Null associations were observed for other antioxidant vitamins. Our prospective study suggests that higher consumption of retinol may be associated with an increased risk of lung cancer in men, especially with small cell carcinoma, although confirmation is required.     

Fruit and vegetable intake and esophageal cancer in a large prospective cohort study

Changing patterns of esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) incidence worldwide suggest distinct etiologies. Although associations between fruit and vegetable intake and both ESCC and EAC have been found in multiple ecological and case-control studies, few prospective studies have investigated these associations. We prospectively examined these associations in 490,802 participants of the National Institutes of Health (NIH)-AARP Diet and Health Study using Cox models adjusted for age, alcohol intake, body mass index, cigarette smoking, education, physical activity and total energy intake. We present hazard ratios and 95% confidence intervals per serving per 1,000 calories. During 2,193,751 person years of follow-up, 103 participants were diagnosed with ESCC and 213 participants with EAC. We found a significant inverse association between total fruit and vegetable intake and ESCC risk (HR: 0.78, 95% CI: 0.67-0.91), but not EAC risk (0.98, 0.90-1.08). In models mutually adjusted for fruit and vegetable intake, the protective association with ESCC was stronger for fruits (0.73, 0.57-0.93) than for vegetables (0.84, 0.66-1.07). When we examined botanical subgroups, we observed significant protective associations for ESCC and intake of Rosacea (apples, peaches, nectarines, plums, pears and strawberries) and Rutaceae (citrus fruits). A significant inverse association between EAC and Chenopodiaceae (spinach) intake was observed. Results from our study suggest that the relation of fruit and vegetable intake and esophageal cancer risk may vary by histologic type.     

Vegetables,fruit and risk of gastric cancer in Japan: a 10-year follow-up of the JPHC Study Cohort I

The association between vegetables and fruit consumption and gastric cancer risk was investigated in a population-based prospective study in 4 public health center areas in Japan. Dietary and other exposure data were obtained in 1990 from a cohort of 19,304 men and 20,689 women with a self-administered questionnaire. After 10 years of follow-up, a total of 404 cases of gastric cancer were documented among them. After adjustment for age, gender, areas and other potential confounding factors and after exclusion of the cases diagnosed in first and second follow-up years, the relative risk associated with intake 1 or more days per week compared to less than 1 day per week was 0.64 (95% CI 0.45-0.92) for yellow vegetable, 0.48 (95% CI 0.25-0.89) for white vegetable and 0.70 (95% CI 0.49-1.00) for fruit. Relative risks associated with quintile of total vegetable consumption were 1.00, 0.86, 0.75, 0.90 and 0.75 (p for trend = 0.17). In the differentiated type of gastric cancer, the association became clearer: 1.00, 0.96, 0.78, 0.88 and 0.53 (p for trend = 0.03). This prospective study suggests that vegetable and fruit intake, even in low amounts, is associated with a lower risk of gastric cancer. Although no striking differences in the association were seen between cardia and noncardia cancer, an inverse association was higher in differentiated rather than in undifferentiated types of gastric cancer.