Dietary carotenoids,vegetables, and lung cancer risk in women: the Missouri women's health study (United States)

Objective: To examine the effect of specific dietary carotenoids and their primary plant food sources on lung cancer risk in a population-based case–control study of women. Methods: Data were available for 587 incident primary lung cancer cases and 624 controls frequency matched to cases based on age. A modified version of the 100-item NCI-Block food-frequency questionnaire was used to obtain information concerning usual diet 2–3 years prior to interview. Results: In models adjusted for age, total calorie intake, pack-years of smoking, and education, -carotene, -cryptoxanthin, lutein + zeaxanthin, and total carotenoid intake were each associated with a significantly lower risk of lung cancer. Several vegetable groups were predictive of lower lung cancer risk, particularly the frequency of total vegetable intake. Individual and total carotenoids were no longer significantly associated with lower lung cancer risk in models adjusted for total vegetable intake. However, total vegetable intake remained significantly inversely associated with risk in models adjusted for total carotenoids. Conclusions: These results indicate that consumption of a wide variety of vegetables has a greater bearing on lung cancer risk in a population of smoking and nonsmoking women than intake of any specific carotenoid or total carotenoids.     

Diet and alcohol consumption and lung cancer risk in the New York State Cohort (United States)

The relationship between diet and alcohol and lung cancer was evaluated among participants of the New York State Cohort (United States),comprising 27,544 men (395 cases) and 20,456 women (130 cases) who completed a brief mailed questionnaire in 1980. Participants were followed up through1987 with the assistance of the New York State Department of Health's Vital Statistics Section and Cancer Registry. Among men, inverse relationships with vitamin C, folate, and carotenoids, and positive associations with total fat, monounsaturated and saturated fat were observed after adjusting for age, education, cigarettes/day, years smoking, and total energy intake. The relationships observed with folate and saturated fat were stronger for heavy smokers. Also, the effect of folate, total fat, and monounsaturated fat seemed to be limited to squamous cell carcinomas. We found no indication that cholesterol or polyunsaturated fat was associated with lung cancer. Diet did not appear to exert a major role on lung cancer risk among women. Although diet modification should never be considered a substitute for smoking cessation, its role as an additional strategy in lung cancer prevention deserves attention. This revised version was published online in July 2006 with corrections to the Cover Date.     

Interaction of family history of breast cancer and dietary antioxidants with breast cancer risk (New York,United States)

We sought to determine if specific dietary antioxidants may be particularly effective in reducing breast cancer risk for women reporting family history (FH) of breast cancer in a first-degree relative. Interviews regarding usual diet, health, and family histories were conducted with 262 premenopausal and 371 postmenopausal women with incident, primary breast cancer from western New York (United States). These women were frequencymatched by age and county of residence with community controls. Among premenopausal women, there was a significant interaction between FH and -tocopherol; -tocopherol was associated with significantly decreased risk among FH+ women (adjusted fourth-quartile odds ratio [OR]=0.01, 95 percent confidence interval [CI]=0.0–0.3). This association was much weaker for FH-women [OR=0.7, CI=0.4–1.2]. For FH-women, a significant inverse association was observed between -carotene and premenopausal breast-cancer risk (OR=0.4, CI=0.3–0.5), but not for FH+ women (OR=0.5, CI=0.1–4.0). Similar relationships, although not as strong, were noted among postmenopausal women. Although limited by small numbers, these results suggest that biologic mechanisms of tumorigenesis may differ in FH+ and FH-women, and that -tocopherol may be a potential chemopreventive agent for women with a family history of breast cancer, particularly premenopausal women.This research was conducted by the Department of Social and preventive Medicine, State University of New York at Buffalo. This publication is supported in part by grants CA11535 and 5 R25 CA1820117 from the US National Cancer Institute and PDT-434 from the American Cancer Society. Dr Freudenheim is a recipient of a Research Career Development Award from the National Cancer Institute (CA01633). This work is solely the responsibility of the authors and does not necessarily represent the views of the NCI.     

Racial differences in the risk of invasive squamous-cell cervical cancer

To investigate reasons for the higher rates of invasive squamous-cell cervical carcinoma among Blacks than Whites in the United States, we examined data from a case-control study of cervical cancer conducted in five geographic areas of the US, supplemented by incidence data from the Surveillance, Epidemiology, and End Results (SEER) Program, and hysterectomy prevalence data from the Cancer and Steroid Hormone Study. We observed only minor differences between Blacks and Whites in the magnitude of relative risks associated with a long interval since last Pap smear, multiple sexual partners, cigarette smoking, a higher number of births, and low levels of income and education. Thus, differences in the strength of associations contributed little to the higher incidence rate in Blacks, but the prevalence of these risk factors, except for cigarette smoking, was higher in Blacks than Whites. The SEER incidence rate ratio of 2.3 for Blacks compared to whites was increased to 2.7 when incidence rates utilized denominators corrected for prevalence of hysterectomy, while the rate difference increased from 14.9 to 25.8 cases per 100,000 person-years (PY). We estimated further that, after adjustment for prevalence of hysterectomy, the incidence rate for women at the lowest levels of exposure to the risk factors evaluated was 2.2 times higher in Blacks than Whites, but that the corresponding rate difference was only 2.2 cases per 100,000 PYs. Thus, our results suggest that racial differences in the prevalence of exposure to identified risk factors account for most of the difference in incidence rates. It remains to be determined what, as yet unidentified, aspects of lower socioeconomic status contribute to the higher incidence rate in Blacks.Authors are with the Epidemiology and Biostatistics Program, Division of Cancer Etiology, National Cancer Institute. Address correspondence to Ms Schairer, Environmental Epidemiology Branch, National Cancer Institute, National Institutes of Health, Executive Plaza North, Room 443, Bethesda, MD 20892, USA.     

Smoking and bladder cancer risk in Blacks and Whites in the United States

A population-based case-control study of bladder cancer (2,982 cases and 5,782 controls) conducted in 10 areas of the United States examined the effect of smoking as a risk factor among Blacks and Whites, after adjustment for occupation and other potential confounders. Although the overall risk for smoking was slightly higher in Blacks than Whites (relative risk = 2.7 and 2.2, respectively), this difference was not statistically significant. Estimation of risk by dose and currency of exposure revealed no consistent racial disparities in smoking-related risks. Race-specific, attributable risk estimates indicated that nearly half of bladder cancers among both Blacks and Whites could have been prevented by elimination of smoking.     

A cohort study of dietary carotenoids and lung cancer risk in women (Canada)

Objective: To investigate the association between dietary carotenoid intake and lung cancer risk in women. Methods: A case–cohort study was undertaken in the Canadian National Breast Screening Study dietary cohort, which consists of 56,837 women who completed a self-administered dietary questionnaire. The cohort was recruited between 1980 and 1985, and during follow-up to the end of 1993 a total of 196 cohort members were diagnosed with incident lung cancer. For analysis, a subcohort consisting of a random sample of 5681 women was selected from the full dietary cohort. After exclusions for various reasons, the analyses were based on 155 cases and 5361 non-cases. Results: When compared to those in the lowest quartile level of intake, the adjusted incidence rate ratios (95% confidence intervals) for those in the highest quartile levels of -carotene, -carotene, -cryptoxanthin, lycopene, and lutein intake were 0.90 (0.51–1.58), 1.40 (0.76–2.59), 0.66 (0.33–1.32), 1.04 (0.61–1.76), and 1.26 (0.70–2.24), respectively; none of the associated tests for trend was statistically significant. Conclusion: These results suggest that there is no association between dietary carotenoid intake and lung cancer risk, at least for the range of intakes observed here.     

A prospective study of whole grains, fruits, vegetables and colon cancer risk

OBJECTIVE: We examined the relation between whole grains, fruit, vegetables and dietary fiber and colon cancer risk in the prospective Cancer Prevention Study II Nutrition Cohort. METHODS: In 1992-1993, 62,609 men and 70,554 women completed questionnaires on medical history, diet and lifestyle behaviors. After exclusions, we confirmed 298 cases of incident colon cancer among men and 210 among women through August 31, 1997. RESULTS: Multivariate rate ratios (RR) and 95% confidence intervals (CI) for all dietary factors were null. However, a statistically non-significant 30% reduction in risk was observed for men with the highest vegetable intakes (RR = 0.69, CI = 0.47-1.03, top versus bottom quintile, p trend = 0.10). Men with very low (lowest tertile within the lowest quintile) intakes of vegetables and dietary fiber were at increased risk compared to those in the highest four quintiles of intake (vegetables RR = 1.79, CI = 1.22-2.61, p trend = 0.04, and fiber RR = 1.96, CI = 1.24-3.10, p trend = 0.006). Women with very low intakes of fruit were also at increased risk (RR = 1.86, CI = 1.18-2.94, p trend = 0.06). CONCLUSIONS: Higher intakes of plant foods or fiber were not related to lower risk of colon cancer. However, our data suggest that very low intakes of plant foods may increase risk, and that certain phytochemical subgroups may decrease risk.     

Incomplete pregnancies and risk of ovarian cancer (Washington, United States)

Because of the reduced risk of ovarian cancer related to prior full-term pregnancies, we sought to determine whether there was any association with a history of one or more incomplete pregnancies. White female residents of three counties in Washington State (United States) diagnosed with ovarian cancer during 1986–88 (n=322), and a random sample of control women selected from these same counties (n=426), were interviewed regarding their pregnancy and childbearing histories. Among women who had given birth to at least one child, an additional incomplete pregnancy was not associated with the risk of ovarian cancer (relative risk [RR]=1.1, 95 percent confidence interval [CI]=0.8–1.6, adjusting for age, oral contraceptive use, and number of births). For those who had never given birth, a somewhat smaller proportion of cases had a history of incomplete pregnancy than controls (RR=0.8, CI=0.4–1.7). In an analysis restricted to ever-pregnant women, a prior induced or spontaneous abortion was not found to be associated with the incidence of ovarian tumors (RR=1.0, CI=0.6–1.7, and RR=1.3, CI=0.8–1.9, respectively). Other studies of the possible relation between incomplete pregnancies and ovarian cancer generally have observed either a weak negative association or no association at all. It is possible that if incomplete pregnancies do affect the risk of ovarian cancer, their impact might be too small to be identified reliably through epidemiologic studies.This research was supported in part by a grant from the US National Cancer Institute (R35 CA39779), and by the Cancer Surveillance System of the Fred Hutchinson Cancer Research Center, which is funded by Contract No. N01-CN-05230 from the Surveillance, Epidemiology and End Results (SEER) program of the National Cancer Institute with additional support from the Fred Hutchinson Cancer Research Center.     

The University of Minnesota Cancer Prevention Research Unit vegetable and fruit classification scheme (United States)

High vegetable and fruit (V&F) intake has been associated with a lower risk of many cancers. However, the specific V&F, the active compounds present in V&F, and the dose at which they confer protection are unknown. Standard methods for assessing, classifying, and quantifying V&F exposures in epidemiologic studies have not been established. Differences among studies occur due to inherent differences among V&F, and across dietary assessment methods, study populations, etiologic hypotheses, and analytic methods. The V&F classification scheme presented here characterizes and quantifies V&F consumption for elucidating risk relationships, identifying chemopreventive compounds present in V&F, and facilitating identification of potential biomarkers of V&F intake. Broad criteria define which plant foods count as V&F. Formation of food groups is based on proposed biological mechanisms of action. Five main groups are included: Total V&F; Total Vegetables; Total Fruits; and two groups orthogonal to these-the Botanical and Phytochemical groups. Subgroups are specified within each main group. V&F exposure is quantified as the absolute amount consumed (weight) or as the number of household servings. This classification scheme has public health applications and may be used to examine associations with chronic diseases other than cancer.Mss Smith and Campbell made equal contributions as first authors to this paper.This work was supported by NCI grants P01 CA50305 and 5 T32 CA 09607 and a Graduate Dissertation Fellowship from the University of Minnesota Graduate School.     

Diet diversity, diet composition, and risk of colon cancer (United States)

In this study, we evaluate diet diversity, diet composition, and risk of colon cancer in an incident population-based study of 1,993 cases and2,410 controls in the Kaiser Permanente Medical Care Program of Northern California, eight counties in Utah, and the Twin Cities area of Minnesota(United States). Ninety-one and one-half percent of the population were non-Hispanic White. Dietary intake was obtained using an adaptation of the CARDIA diet-history questionnaire. Diet diversity was defined as the number of unique food items reported; diversity also was explored within six major food groups. Composition of the diet was described by estimating the proportion of total number of food items contributed by major food groups. Younger individuals, higher educated individuals, and those who lived in larger households reported eating the most diverse diet. Total diet diversity was not associated with colon cancer. However, eating a diet with greater diversity of meats, poultry, fish, and eggs, was associated with a50 percent increase in risk among all men (95 percent confidence interval[CI] = 1.1-2.0; P trend = 0.01), with slightly stronger associations for younger men and men with distal tumors. A diet with a greater number of refined grain products also was associated with increased risk among men(odds ratio [OR] = 1.7, CI = 1.3-2.3). Women who ate a diet with a more diverse pattern of vegetables were at approximately a 20 percent lower risk than women who had the least diverse diet in vegetables. Assessment of diet composition showed that men who consumed a large proportion of their food items from meat, fish, poultry, and eggs were at an increased risk, with the most marked association being for distal tumors (OR = 1.7, CI = 1.2-2.5).Women who consumed the largest percentage of their food items in the form of plant foods (fruits, vegetables, or whole grains) were at a reduced risk of developing colon cancer (OR = 0.7, CI = 0.5-1.0). This revised version was published online in July 2006 with corrections to the Cover Date.     

Attributable risk of lung cancer in lifetime nonsmokers and long-term ex-smokers (Missouri,United States)

A population-based, case-control study of incident lung cancer among women in Missouri (United States) who were lifetime nonsmokers and long-term ex-smokers was conducted between 1986 and 1992. The study included 618 lung cancer cases and 1,402 population-based, age matched controls. Information on lung-cancer risk factors was obtained by interviewing cases, next-of-kin of cases (36 percent and 64 percent of the cases, respectively) and controls. Year-long radon measurements also were sought in every dwelling occupied for the previous five to 30 years. Population attributable risks (PAR) for specific risk factors were computed for all subjects, for lifetime nonsmokers, for long-term ex-smokers, by histologic cell type (i.e., adenocarcinoma cf nonadenocarcinoma) and for direct interviews with case (for living cases) and for next-of-kin interviews (for dead cases or cases too ill to complete an interview). The mean age at lung cancer diagnosis was 71 years, and nearly 50 percent of the lung cancers were histologically confirmed adenocarcinomas. Almost 40 percent of all lung cancers among lifetime nonsmokers and almost 50 percent of lung cancers among all subjects could be explained by the risk factors under study. Dietary intake of saturated fat and nonmalignant lung disease were the two leading identified risk factors for lung cancer among the lifetime nonsmokers, followed by environmental tobacco smoke, and occupational exposures to known carcinogens. A small nonsignificant risk was found for study subjects exposed to median domestic radon concentration of 4 pCi/l (25-year time-weight average). Since only a small fraction of the population is exposed at this level, it is estimated that the PAR for domestic radon was less than two percent in Missouri. The risk for saturated fat intake was similar for lifetime nonsmokers, ex-somkers, adenocarcinoma cases, and nonadenocarcinoma cases; however, the increased risk was much more pronounced for next-of-kin interviews (PAR=31 percent) than for interviews with the study subjects (PAR = nine percent). A similar pattern of PAR was identified among ex-smokers but, in this group, the lingering effect of a history of smoking was also very important. Along with saturated fat intake (PAR=20 percent), the combined effect of previous active and passive smoking even after 15 years of cessation of active smoking was responsible for more lung cancer than any other risk factor under study (PAR=59 percent).Drs Alavanja, Benicbou, Swanson, and Boice are with the Epidemiology and Biostatistics Program, National Cancer Institute, Bethesda, MD, USA. Dr Brownson is with the Department of Community Health, Saint Louis University School of Public Health, St Louis, MO, USA. Address correspondence to Dr Alavanja, Epidemiology and Biostatistics Program, National Cancer Institute, EPN/543, 6130 Executive Blvd, Bethesda, MD 20892, USA.     

Intakes of fruits and vegetables,carotenoids and vitamins A,E, C in relation to the risk of bladder cancer in the ATBC cohort study

We examined the relation between dietary fruit and vegetables, carotenoids and vitamin intakes and the risk of bladder cancer among male smokers in a prospective 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 questionnaire 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.     

Occupational risk factors for lung cancer among nonsmoking women: a case-control study in Missouri (United States)

Occupationally related risk of lung cancer among women and among nonsmokers has not been widely studied. A recently conducted population-based, case-control study in Missouri (United States) provided the opportunity to evaluate risk of lung cancer associated with several occupational factors. Incident cases (n=429) were identified through the Missouri Cancer Registry for the period 1986 through 1991, and included 294 lifetime nonsmokers and 135 ex-smokers who had stopped at least 15 years prior to diagnosis or had smoked for less than one pack-year. Controls (n=1,021) were selected through driver's license and Medicare files. Risk was elevated among women exposed to asbestos (ever: odds ratio [OR]=3.5, 95 percent confidence interval [CI]=1.2–10.0; >9 yrs: OR=4.6, CI=1.1–19.2) and pesticides (ever: OR=2.4, CI=1.1–5.6; >17.5 yrs: OR=2.4, CI=0.8–7.0). Risk also was elevated among dry cleaning workers (ever: OR=1.8, CI=1.1–3.0; >1.125 yrs: OR=2.9, CI=1.5–5.4). Occupational risks for lung cancer among women merit further study.Drs Brownson and Chang are with the Missouri Department of Health, Columbia, MO, USA. Dr Alavanja is with the Epidemiology and Biostatistics Program, National Cancer Institute, Rockville, MD, USA. Dr Chang directs the Missouri Cancer Registry with the Missouri Department of Health. Address correspondence to Dr Brownson, Division of Chronic Disease Prevention and Health Promotion, Missouri Department of Health, 201 Business Loop 70 West, Columbia, MO 65203, USA. This study was supported in part by US National Cancer Institute contracts NO1-CP7-1096-01 and NO1-CP7-1096-02.     

Diabetes mellitus and risk of prostate cancer (United States)

A lower risk of prostate cancer among diabetics has been suggested by several but not all studies. However, the studies have not always accounted for time since diagnosis of diabetes mellitus, or have not examined confounding factors such as diet and diagnostic bias. We thus examined this relationship in the Health Professionals Follow-Up Study from 1986 and 1994, in which 1,369 new cases of non-stage A1 prostate cancer were documented in 47,781 men. A prior history of a diagnosis of diabetes (mostly adult-onset) was associated with a reduced risk of prostate cancer (multivariate relative risk [RR] = 0.75; 95 percent confidence interval [CI] = 0.59-0.95) controlling for age, body mass index (wt/ht2) at age 21, and, in 1986, race, vasectomy, and intakes of total energy, total fat, calcium, fructose, and lycopene. After excluding the first year of follow-up after the diagnosis of diabetes, the RR was 0.63 (CI = 0.54-0.89). Prostate cancer was not reduced in the first five years after diagnosis (RR = 1.24, CI = 0.87-1.77), but was lower in the next five years (RR = 0.66, CI = 0.39-1.10) and lowest after 10 years (RR = 0.54, CI = 0.37-0.78); P-value for trend across time = 0.004. Similar associations were noted for advanced cases. Detection bias was unlikely to account for our findings. The basis of this relationship is unclear but may reflect hormonal changes related to diabetes, perhaps low testosterone levels.     

Increasing incidence of colon and rectal cancer among Hispanics and American Indians in New Mexico (United States), 1969-94

Objectives: This study evaluates time trends in colon and rectal cancer incidence and mortality among the three major race/ethnic groups (Hispanics, American Indians, and non-Hispanic Whites) in New Mexico (United States). Methods: We used data from the New Mexico Tumor Registry (NMTR) and computed average annual age-standardized incidence and mortality rates. Colon cancer incidence rates were further examined by anatomical subsite. Estimated annual percent change (EAPC) in incidence and mortality over time were computed using Poisson regression. Results: Invasive colorectal cancer incidence rates increased from 1969-89 in all three race/ethnic groups, but decreased among non-Hispanic Whites in 1990-94, while rates continued to increase among minority populations, especially among minority men. Over the 26-year period, EAPC in colon cancer incidence among men was 3.6 percent for Hispanics, 4.7 percent for American Indians, and 0.7 percent for non-Hispanic Whites. Right-sided colon cancers were more common among American Indian women, and among all women aged 65 years and older. Mortality rates decreased steadily among non-Hispanic Whites over the study period, especially among women. Conclusions: Studies are needed to identify important modifiable risk factors and to develop strategies to increase the use of colorectal cancer screening-procedures among the minority populations.     

Dietary cholesterol,fat, and lung cancer incidence among older women: The Iowa Women's Health Study (United States)

To test the hypothesis that a high intake of dietary cholesterol and fat is associated with elevated risks of lung cancer, we analyzed data from a population-based, prospective, cohort study conducted among 41,837 postmenopausal Iowa (United States) women who completed, in 1986, a comprehensive mailed questionnaire including information on usual intake of 127 food items. All cohort members were followed for cancer incidence through the statewide cancer registry. By 1991, after six years of follow-up, 272 incident lung-cancer cases were identified. After controlling for total energy intake and other confounding factors, dietary cholesterol, total fat, and animal fat were unrelated to lung cancer risk. Intake in the upper three quartiles of plantderived fat, however, was related to a 30 to 40 percent lower incidence of lung cancer, compared with those in the lowest quartile, with more pronoucned reduction in risk observed among smokers (relative risk=0.6, 95 percent confidence interval=0.4–0.9). This prospective cohort study suggests that high intake of fat of plant origin may be associated with reduced risk of lung cancer, while dietary cholesterol and animal fat intake is unrelated to the etiology of this malignancy in postmenopausal women.This study was supported by grant R01 CA 39742 of the US National Cancer Institute.     

Glycosylated hemoglobin and risk of colorectal cancer and adenoma (United States)

Objectives: The consistently observed epidemiologic associations of obesity and physical activity with colorectal cancer and precursor adenoma risk suggest that insulin and glucose control may be contributory. We evaluated the association of glycosylated hemoglobin (HbA_1c), a clinical indicator of average glycemia over the previous 2 months, and possibly, indirectly, a marker of average blood insulin level, with colorectal carcinogenesis.Methods: Among women in the Nurses' Health Study, who provided blood in 1989–90 and were diagnosed subsequently in 1989–94, we included 79 colorectal cancer cases and 156 matched controls, and 201 distal colorectal adenoma cases and 201 matched controls. HbA_1c concentrations in red blood cells were determined blindly by turbidometric immunoinhibition. Odds ratios (OR) and 95% confidence intervals (CI) were estimated from conditional logistic regression models.Results: HbA_1c level did not significantly differ between colorectal cancer cases (median 5.5%) and controls (5.5%, p = 0.5), although a small difference between adenoma cases (5.6%) and controls (5.5%, p = 0.06) was noted. Compared to the lowest tertile of HbA_1c (median 5.2%), women in the middle (median 5.5%, OR = 1.2, CI = 0.6–2.5) and upper (5.8%, OR = 1.2, CI = 0.6–2.7) tertiles were not at an increased risk for colorectal cancer. A modestly elevated risk of distal colorectal adenoma in the upper (median 5.8%, OR = 1.4, CI = 0.9–2.3) versus lower (median 5.3%) tertile could not be excluded. These associations were not appreciably altered after adjusting for known and suspected colorectal cancer risk factors.Conclusion: Over the range of levels observed in this relatively small sample of middle-aged women, prediagnostic HbA_1c does not clearly predict colorectal cancer and adenoma 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.     

Diet in the epidemiology of endometrial cancer in Western New York (United States)

Objectives: We examined diet and risk of endometrial cancer among women in the Western New York Diet Study (1986–1991). Methods: Self-reported frequency of use of 172 foods and beverages during the 2 years before the interview and other relevant data were collected by detailed interviews from 232 endometrial cancer cases and 639 controls, frequency-matched for age and county of residence. Odds ratios (OR) and 95% confidence intervals (CI) were estimated by unconditional logistic regression, adjusting for age, education, body mass index (BMI), smoking history, hypertension, diabetes, age at menarche, parity, oral contraceptive use, menopausal status, menopausal estrogen use, and energy. Results: Risks were reduced for women in the highest quartiles of intake of protein (OR 0.4, 95% CI: 0.2–0.9), dietary fiber (OR 0.5, 95% CI: 0.3–1.0), phytosterols (OR 0.6, 95% CI: 0.3–1.0), vitamin C (OR 0.5, 95% CI: 0.3–0.8) folate (OR 0.4, 95% CI: 0.2–0.7), alpha-carotene (OR 0.6, 95% CI: 0.4–1.0), beta-carotene (OR 0.4, 95% CI: 0.2–0.6), lycopene (OR 0.6, 95% CI: 0.4–1.0), lutein + zeaxanthin (OR 0.3, 95% CI: 0.2–0.5) and vegetables (OR 0.5, 95% CI: 0.3–0.9), but unrelated to energy (OR 0.9, 95% CI: 0.6–1.5) or fat (OR 1.6, 95% CI: 0.7–3.4). Conclusions: Our results support previous findings of reduced endometrial cancer risks associated with a diet high in plant foods.     

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.