Vegetable and fruit consumption and lung cancer risk in the Netherlands Cohort Study on Diet and Cancer

Objective: The purpose was to study the association between vegetable and fruit consumption and lung cancer incidence using 1074 cases after 6.3 years of follow-up in the Netherlands Cohort Study. Methods: Dietary intake was assessed using a 150-item food-frequency questionnaire. Multivariate models were used including age, sex, family history of lung cancer, highest educational level attained, and smoking history. Results: Statistically significant inverse associations were found with total vegetables and most vegetable groups. Rate ratios (RRs) based on consumption frequency showed the strongest effect of vegetables from the Brassica group (RR 0.5, 95% confidence interval (95% CI) 0.3–0.9, for consumption 3 times per week versus once a month). RR of highest versus lowest quintile of total vegetable consumption was 0.7 (95% CI 0.5–1.0, p-trend 0.001). Statistically significant inverse associations were found for all fruits listed in the questionnaire. RRs for quintiles of total fruit intake were 1.0, 0.7, 0.6, 0.6 and 0.8 respectively (p-trend < 0.0001). Protective effects of fruits and vegetables were stronger in current than in former smokers, and weaker for adenocarcinomas than for other types of tumors. Conclusions: Inverse associations with lung cancer are found for both vegetable and fruit intake, but no specific type of vegetable or fruit seems to be particularly responsible.     

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.     

Body mass index and mortality from lung cancer in smokers and nonsmokers: A nationally representative prospective study of 220,000 men in China

Low body mass index (BMI) has been associated with increased risk of lung cancer. However, the nature of the association, especially in populations with relatively low BMI, is less well characterized, as is the relevance to it of smoking. A nationally representative prospective cohort study included 217,180 Chinese men aged 40–79 years in 1990–91 who had no prior history of cancer and were followed up for 15 years. Standardized hazard ratios (HRs) were calculated for lung cancer mortality by baseline BMI. The mean baseline BMI was 21.7 kg/m², and 2,145 lung cancer deaths were recorded during 15 years of follow‐up. The prevalence of smoking was strongly inversely associated with BMI, but no apparent relationship was seen between amount smoked (or other measures of smoking intensity) and BMI among smokers. Overall there was a strong inverse association between BMI and lung cancer mortality (p < 0.0001 for trend) after excluding the first 3 years of follow‐up. This association appeared to be confined mainly to current smokers, with no apparent relationship in nonsmokers (p < 0.001 for difference between slopes). Among current smokers, the inverse association appeared to be log‐linear, with each 5 kg/m² lower BMI associated with a 35% (95% confidence interval: 24–46%; p < 0.0001) higher lung cancer mortality, and it persisted after excluding those who had reported poor health status or history of any disease or respiratory symptoms at baseline. In this relatively lean Chinese male population, low BMI was strongly associated with increased risk of lung cancer only among current smokers. © 2009 UICC     

Vegetables and fruit intake and cancer mortality in the Hiroshima/Nagasaki Life Span Study

The association between green-yellow vegetables and fruit consumption and risk of cancer death was investigated in a prospective study of 38 540 men and women who were atomic-bomb survivors in Hiroshima and Nagasaki, Japan. Study participants completed a dietary questionnaire in 1980-1981 and were followed-up for cancer deaths until March 1998, during which time 3136 cancer deaths were identified. Daily or almost daily fruit consumption was associated with a significant 12% reduction in total cancer mortality (RR=0.88; 95% CI, 0.80-0.96 for daily intake compared with intake once per week or less). Daily or almost daily green-yellow vegetables consumption was associated with a marginally significant 8% reduction in total cancer mortality (0.92; 0.94-1.01). Green-yellow vegetables consumption was associated with a significant reduction in liver cancer mortality (0.75; 0.60-0.95). Fruit consumption was associated with a significantly reduced risk of stomach cancer and lung cancer mortality (0.80; 0.65-0.98). Green-yellow vegetables and fruit consumption was associated with a reduction in oesophageal cancer, but these associations were not statistically significant. Neither green-yellow vegetables nor fruit consumption was associated with colorectal cancer or breast cancer mortality. These results support the evidence that daily consumption of fruit and vegetables reduces the risk of total cancer, and specifically cancers of the stomach, liver, and lung.     

Attributable and absolute risk of lung cancer death by smoking status: findings from the Japan Collaborative Cohort Study

Estimating the proportion of lung cancer deaths that can be avoided is important in assessing the potential impact of antismoking efforts on the reduction of lung cancer deaths. We calculated the population attributable risk (PAR) and absolute risk of lung cancer death according to smoking status based on the Japan Collaborative Cohort (JACC) Study. The analytic cohort included 45,010 males and 55,724 females aged 40-79 years. Cox proportional hazards model was used to determine age-adjusted relative risks and PAR according to smoking status. We also computed lung cancer mortality according to age and smoking status. In males, 52.2% and 14.8% of lung cancer deaths were attributable to current and former cigarette smoking, respectively. In females, the corresponding figures were 11.8% and 2.8%. Among current male smokers, the relative risk was strongly correlated with the intensity and duration of cigarette smoking. In contrast, the PAR was associated with an intermediate level of smoking except for the years of smoking: the largest PARs were observed in those with 20-29 cigarettes per day, 40-59 pack-years and 20-22 years old at starting smoking. Absolute risks were estimated to increase with age and duration of smoking and not to decrease even after cessation. These findings suggest that avoidable lung cancer deaths are primarily among light to moderate smokers who are considered amenable to population-based antismoking strategies. For all current smokers, immediate cessation is encouraged because it offers the only realistic way to avoid a substantial increase in lung cancer mortality brought about by further continuation of smoking.     

Prospective study of vegetable consumption and liver cancer in Japan

We examined the relationship between vegetable consumption and the risk of death from liver cancer in a cohort study in Japan. This analysis is based on data from 6,049 subjects aged 40 to 79 years enrolled in a cohort study conducted in Fukuoka Prefecture, Japan. The follow-up period was from 1986 to 1999. All liver cancer deaths were recorded. The vegetable consumption was classified into 3 groups: "once per week or less," "2-4 times per week" and "daily intake." The Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence interval (95% CI). A total of 51 male and 22 female liver cancer deaths were recorded during 62,343 person-years of follow-up. The "once per week or less" group was considered the referent group. In males, the multivariate HRs of liver cancer deaths were 0.61 (95% CI: 0.33-1.14) and 0.25 (95% CI: 0.11-0.59) in the "2-4 times per week" and "daily intake" groups, respectively. In females, the multivariate HRs were 0.44 (95% CI: 0.13-1.51) and 0.51 (95% CI: 0.16-1.69), respectively. The multivariate HRs were also reported by history of hepatitis and cirrhosis. In those without a history of these conditions, the multivariate HRs were 0.54 (95% CI: 0.27-1.09) and 0.36 (95% CI: 0.16-0.83). In those with a history of these conditions, the multivariate HRs were 0.58 (95% CI: 0.22-1.56) and 0.37 (95% CI: 0.13-1.06), respectively. Our study reveals an inverse association between vegetable consumption and the risk of death from liver cancer. These results provide further evidence of the protective effect of vegetables against liver cancer.     

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.     

Tuberculosis,smoking and risk for lung cancer incidence and mortality

Among the exposures associated with risk for lung cancer, a history of tuberculosis (TB) is one potentially important factor, given the high prevalence of TB worldwide. A prospective cohort study was conducted to evaluate the associations of preexisting pulmonary TB with lung cancer incidence and mortality. The cohort consisted of 1,607,710 Korean adults covered by the National Health Insurance System who had a biennial national medical examination during 1997–2000. During up to 16 years of follow‐up, there were 12,819 incident cases of lung cancer and 9,562 lung cancer deaths. Using Cox proportional hazards models and controlling for age, cigarette smoking and other covariates, the presence of underlying TB was significantly associated with increased risk for lung cancer incidence (HR 1.37 in men with 95% CI 1.29–1.45; HR 1.49 in women with 95% CI 1.28–1.74) and mortality (HR 1.43 in men with 95% CI 1.34–1.52; HR 1.53 in women with 95% CI 1.28–1.83). We also observed a dose‐response relationship between number of cigarettes smoked daily and lung cancer risk. There was no evidence for synergism between a history of TB and smoking. The elevation in risk is relatively modest, particularly in comparison to that from smoking, and a prior history of TB is not likely to be useful risk indicator for clinical purposes. In populations with high prevalence of TB, it can be considered for incorporation into models for lung cancer risk prediction.     

Neutrophil-to-lymphocyte ratio and risk of lung cancer mortality in a low-risk population: A cohort study

Neutrophil-to-lymphocyte ratio (NLR) is associated with poor prognosis in patients with lung cancer, but the predictive role of NLR on the risk of developing lung cancer is unknown. We investigated the association between NLR and lung cancer mortality in lung cancer-free adults. A cohort study was performed with 527,124 Korean adults who were free of lung cancer and were followed for up to 16 years. Vital status and lung cancer-related deaths were ascertained through national death records. Hazard ratios (HRs) and 95% confidence intervals (CIs) for lung cancer mortality were estimated using a Cox proportional hazards model. During 4,567,495.8 person-years of follow-up, 574 lung cancer deaths were identified. A higher NLR was positively associated with lung cancer mortality. The multivariable-adjusted HR (95% CI) for lung cancer mortality comparing quintiles 2, 3, 4 and 5 of NLR to the lowest quintile were 1.26 (0.96–1.67), 1.23 (0.93–1.63), 1.33 (1.01–1.75) and 1.47 (1.13–1.92), respectively. The highest risk of lung cancer mortality was also observed in the highest NLR quintile among never-smokers and low-risk individuals after adjusting for lung function and other possible confounders. Platelet-to-lymphocyte ratio showed an inverse J-shaped association with lung cancer mortality in men but the trends in women, low-risk individuals or never-smokers were neither linear nor U-shaped. In this large cohort of young and middle-aged individuals, NLR was independently associated with increased risk of lung cancer mortality in low-risk individuals, indicating a role of systemic inflammation in lung cancer mortality in our study population.     

Physical activity and lung cancer risk in the European Prospective Investigation into Cancer and Nutrition Cohort

Research conducted predominantly in male populations on physical activity and lung cancer has yielded inconsistent results. We examined this relationship among 416,277 men and women from the European Prospective Investigation into Cancer and Nutrition (EPIC). Detailed information on recent recreational, household and occupational physical activity, smoking habits and diet was assessed at baseline between 1992 and 2000. Relative risks (RR) were estimated using Cox regression. During 6.3 years of follow-up we identified 607 men and 476 women with incident lung cancer. We did not observe an inverse association between recent occupational, recreational or household physical activity and lung cancer risk in either males or females. However, we found some reduction in lung cancer risk associated with sports in males (adjusted RR = 0.71; 95% confidence interval 0.50-0.98; highest tertile vs. inactive group), cycling (RR = 0.73; 0.54-0.99) in females and non-occupational vigorous physical activity. For occupational physical activity, lung cancer risk was increased for unemployed men (adjusted RR = 1.57; 1.20-2.05) and men with standing occupations (RR = 1.35; 1.02-1.79) compared with sitting professions. There was no evidence of heterogeneity of physical activity associations across countries, or across any of the considered cofactors. For some histologic subtypes suggestive sex-specific reductions, limited by subgroup sizes, were observed, especially with vigorous physical activity. In total, our study shows no consistent protective associations of physical activity with lung cancer risk. It can be assumed that the elevated risks found for occupational physical activity are not produced mechanistically by physical activity itself but rather reflect exposure to occupation-related lung cancer risk factors.     

Fruit and vegetable consumption in relation to ovarian cancer incidence: the Swedish Mammography Cohort

We prospectively examined the incidence of epithelial ovarian cancer and its subtypes in relation to baseline fruit and vegetable consumption in the Swedish Mammography Cohort, a population-based cohort study of 61 084 women aged 38-76 years in 1987-1990. During an average follow-up of 13.5 years, 266 incident cases of invasive epithelial ovarian cancer were diagnosed. After adjustment for potential confounders, we observed a statistically significant inverse association between consumption of vegetables and ovarian cancer risk (P-value for trend=0.01); the multivariate rate ratio (RR) for the comparison of three or more servings of vegetables per day with one or fewer servings per day was 0.61 (95% confidence interval (CI), 0.38-0.97). For fruit consumption a modest, not statistically significant, positive association was found (P-value for trend=0.07); the multivariate RR for the highest compared with the lowest category of consumption being 1.37 (95% CI, 0.90-2.06). The associations with fruit and vegetable consumption did not vary by subtype of ovarian cancer. These findings suggest that high consumption of vegetables, but not of fruits, may reduce the risk of ovarian cancer.     

Lung cancer risks in relation to vegetable and fruit consumption and smoking

In a case-control study on lung cancer, risk was analysed in relation to smoking habits and frequency of vegetable and fruit consumption. Lung cancer cases in West Sweden and population controls were interviewed using a questionnaire where the frequency of consumption of dietary items and smoking habits were assessed. The material presented comprises 177 female and 359 male confirmed cases of lung cancer and 916 population controls. There was a dose-response relationship in regard to the number of cigarettes smoked and the number of years smoked, the latter factor being more important. After adjustment for number of cigarettes smoked/day and number of years smoked, the risk for those who seldom consumed vegetables was about twice of that among those who consumed vegetables frequently, both among nonsmokers, smokers and former smokers. This risk increase in relation to vegetable consumption also was present for different smoking categories. A similar tendency, although less pronounced, was found for fruit consumption. The results demonstrate that dietary factors are related to the risk for lung cancer, although smoking is the dominant risk factor.     

Impact of the American anti-smoking campaign on lung cancer mortality

Customary statistics on smoking practices are limited because they do not correlate well with the frequency of smoking-related diseases. Our study developed outcome measures based on lung cancer mortality and used them to assess the anti-smoking campaign. Changes in mortality from lung cancer were used to assess significant smoking among 5-year birth cohorts of white men born from 1901 to 1942. We used each cohort's lung cancer mortality rate at ages 40-44 to indicate its earlier smoking. A lung cancer mortality ratio was developed to describe each cohort's continued smoking from ages 40-44 to 55-59. These ratios were then compared with the durations of the cohorts' exposure to the anti-smoking campaign that began in 1965. Lung cancer mortality in white men ages 40-44 peaked in 1970 and declined continuously thereafter, indicating that the anti-smoking campaign promptly reduced significant smoking among younger men. However, the lung cancer mortality ratio indicates that only half of smokers in the specified birth cohorts were able to quit by ages 55-59, despite receiving ever more intense anti-smoking messages. The anti-smoking campaign produced moderate benefits among younger white male smokers but fewer benefits among older smokers because of the existence of a large number of inveterate smokers.     

A case-control study in Shanghai of fruit and vegetable intake and endometrial cancer

In a population-based case-control study of 832 incident endometrial cancer cases and 846 frequency-matched controls among Chinese women in Shanghai, using a validated food-frequency questionnaire, dietary habits were estimated by in-person interviews. Total vegetable consumption was inversely associated with endometrial cancer risk (highest quartile vs lowest: OR=0.69, 95% CI 0.50-0.96). The risk was reduced with increasing intake of dark green/dark yellow vegetables (trend test, P=0.02), fresh legumes (trend test, P<0.01), and allium vegetables (trend test, P=0.04). Fruit consumption was unrelated to risk. These results suggest that high consumption of certain vegetables may reduce the risk of endometrial cancer.     

The cumulative risk of lung cancer among current, ex- and never-smokers in European men

Recent analyses based on UK data indicate that people who stop smoking, even well into middle age, avoid most of their subsequent risk of lung cancer. We investigated whether similar absolute risks of lung cancer in men are found in other European countries with different smoking patterns and at different stages of their lung cancer epidemic. Using data for men from a multicentre case-control study of lung cancer in the UK, Germany, Italy and Sweden, and including 6523 lung cancer cases and 9468 controls, we combined odds ratio estimates with estimates of national lung cancer incidence rates to calculate the cumulative risk of lung cancer among men by age 75. Lung cancer cumulative risks by age 75 among continuing smokers were similar for the UK, Germany and Italy at 15.7, 14.3 and 13.8% respectively, whereas the cumulative risk among Swedish male smokers was 6.6%. The proportion of the risk of lung cancer avoided by quitting smoking before the age of 40 was comparable between the four countries, at 80% in Italy and 91% in the UK, Germany and Sweden. Similarly, the proportion of the excess risk avoided by quitting before the age of 50 ranged from 57% in Italy to 69% in Germany. Our results support the important conclusion that for long-term smokers, giving up smoking in middle age avoids most of the subsequent risk of lung cancer, and that lung cancer mortality in European men over the next three decades will be determined by the extent to which current smokers can successfully quit smoking.     

Differential effects of smoking on lung cancer mortality before and after household stove improvement in Xuanwei,China

Background:

In Xuanwei County, Yunnan Province, China, lung cancer mortality rates in both males and females are among the highest in China.

Methods:

We evaluated differential effects of smoking on lung cancer mortality before and after household stove improvement with chimney to reduce exposure to smoky coal emissions in the unique cohort in Xuanwei, China. Effects of independent variables on lung cancer mortality were measured as hazard ratios and 95% confidence intervals using a multivariable Cox regression model that included separate time-dependent variables for smoking duration (years) before and after stove improvement.

Results and conclusion:

We found that the effect of smoking on lung cancer risk becomes considerably stronger after chimney installation and consequent reduction of indoor coal smoke exposure.     

新鲜水果摄入可能降低食管癌长期死亡风险

目的：探究新鲜水果摄入是否可以降低食管癌的长期死亡风险。方法：1985年3 月选取林县年龄为40～69岁受试者29479 例,开展基线人口特征、生活习惯、疾病史和回顾性膳食调查,随后对该人群进行随访至2015年12月约31.79年。以食管癌的死亡病例为研究终点,利用Cox 等比例风险模型估计基线新鲜水果摄入对食管癌死亡风险的长期影响。结果：31.09% 的受试人群基线调查报告每周摄入新鲜水果1 次以上。与不食用新鲜水果的人群相比,每周摄入新鲜水果1 次以上食管癌的长期死亡风险降低7% ,这种现象在男性（11%）和吸烟人群（13%）中尤为明显。结论：新鲜水果的摄入可能降低食管癌的长期死亡风险,其详细的病因学机制仍需进一步研究。     

Dietary intake of fruit and vegetable and lung cancer risk: a case-control study in Harbin, northeast China.

BACKGROUND: We studied the relationship between dietary intake of vegetables and fruit and lung cancer risk in Harbin, Heilongjiang province, northeast China, an area with a very high baseline risk of lung cancer in both sexes. PATIENTS AND METHODS: We used data from a case-control study, conducted from 1987 to 1990, among 218 cases with incident, histologically confirmed lung cancer and 436 controls admitted to the same hospitals as cases with non-neoplastic, non-lung diseases unrelated to smoking and other potential risk factors for lung cancer. RESULTS: Compared with the lowest tertile of intake of vegetables, fruit or both, the multivariate odds ratios (ORs) for the highest tertile of intake were 0.39 [95% confidence interval (CI) 0.25-0.62], 0.73 (95% CI 0.48-1.11) and 0.40 (95% CI 0.25-0.63), respectively. In particular, high intake of Chinese cabbage (OR = 0.53), chives (OR = 0 .54), carrots (OR = 0.51) and celery (OR = 0.40) was inversely associated with lung cancer. The OR was more than six-fold elevated for smokers reporting low intake of vegetables, and more than four-fold elevated for smokers reporting low intake of fruit, as compared with never smokers reporting high intake of these items. CONCLUSION: In agreement with previous studies, we found an inverse relation between vegetable and fruit intake and lung cancer risk in both strata of current and never smokers.     

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.     

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.