Consumption of fruits,vegetables and fruit juices and differentiated thyroid carcinoma risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

Fruit and vegetable (F&V) intake is considered as probably protective against overall cancer risk, but results in previous studies are not consistent for thyroid cancer (TC). The purpose of this study is to examine the association between the consumption of fruits, vegetables, fruit juices and differentiated thyroid cancer risk within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The EPIC study is a cohort including over half a million participants, recruited between 1991 and 2000. During a mean follow‐up of 14 years, 748 incident first primary differentiated TC cases were identified. F&V and fruit juice intakes were assessed through validated country‐specific dietary questionnaires. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression models adjusted for potential confounding factors. Comparing the highest versus lowest quartile of intake, differentiated TC risk was not associated with intakes of total F&V (HR: 0.89; 95% CI: 0.68–1.15; p‐trend = 0.44), vegetables (HR: 0.89; 95% CI: 0.69–1.14; p‐trend = 0.56), or fruit (HR: 1.00; 95% CI: 0.79–1.26; p‐trend = 0.64). No significant association was observed with any individual type of vegetable or fruit. However, there was a positive borderline trend with fruit juice intake (HR: 1.23; 95% CI: 0.98–1.53; p‐trend = 0.06). This study did not find any significant association between F&V intakes and differentiated TC risk; however a positive trend with fruit juice intake was observed, possibly related to its high sugar content.     

Consumption of vegetables and fruits and risk of subtypes of head–neck cancer in the Netherlands Cohort Study

There is limited prospective data on the relationship between consumption of vegetables and fruits and the risk of head–neck cancer (HNC) subtypes [i.e., oral cavity cancer (OCC), oro‐/hypopharyngeal cancer (OHPC) and laryngeal cancer (LC)]. Therefore, we investigated these associations within the Netherlands Cohort Study, in which 120,852 participants completed a 150‐item food frequency questionnaire at baseline in 1986. After 20.3 years of follow‐up, 415 cases of HNC (131 OCC, 88 OHPC, three oral cavity/pharynx unspecified or overlapping and 193 LC) and 3,898 subcohort members were available for case–cohort analysis using Cox proportional hazards models. Total vegetable and fruit consumption was inversely associated with risk of HNC overall [multivariable‐adjusted rate ratios for highest vs. lowest quartile: 0.61, 95% confidence interval (CI) 0.44–0.85, p trend 0.002] and all HNC subtypes, with the strongest associations for OCC. Total vegetable intake and total fruit intake were also associated with a decreased risk of HNC overall and HNC subtypes. No significant interaction was found between vegetable and fruit intake and alcohol consumption or cigarette smoking. In conclusion, in this large‐scale cohort study, consumption of vegetables and fruits was associated with a decreased risk of HNC overall and all subtypes. Consumption of vegetables and fruits (or of specific groups of them) may protect against HNC and its subtypes.     

Consumption of fruit, vegetables, and other food groups and the risk of nasopharyngeal carcinoma

Purpose

The role of dietary habits in the etiology of nasopharyngeal carcinoma (NPC) has been extensively investigated in high-incidence areas, but evidence is scanty in low-incidence populations. This study aimed to investigate the relationship between NPC risk and a wide range of food groups in the Italian population.

Methods

We conducted a hospital-based case–control study in Italy on 198, histologically confirmed, NPC cases of Caucasian ethnicity, aged 18–76 years. Controls were 594 Caucasian cancer-free patients admitted to general hospitals for acute conditions. Odds ratios (ORs) and the corresponding confidence intervals (CIs) were estimated through logistic regression, adjusting for socio-demographic characteristics, tobacco smoking, alcohol drinking, and energy intake.

Results

Elevated vegetable consumption was inversely related to NPC risk (OR for highest vs. lower quartile = 0.51; 95 % CI 0.29–0.90). The association was particularly strong for yellow- or red-pigmented vegetables (OR = 0.31; 95 % CI 0.18–0.54), and this effect was stronger among never smokers (OR = 0.18; 95 % CI 0.06–0.55) than among ever smokers (OR = 0.37; 95 % CI 0.19–0.71). Increased NPC risk emerged for elevated eggs consumption (OR = 2.50; 95 % CI 1.44–4.32; p-trend <0.01). No significant associations emerged between NPC risk and consumption of cereals, meat, fish, dairy products, and sweets.

Conclusions

The study findings show that, also in low-risk populations, vegetable consumption is a protective factor against NPC. The stronger effect for yellow- or red-pigmented vegetables is in agreement with the inverse association reported for carotenoids intake.     

Consumption of vegetables and fruits and urothelial cancer incidence: a prospective study.

Although most epidemiological studies concerning urothelial cancer support a possible protective effect of vegetable and fruit consumption, previous studies have been inconsistent with regard to which vegetables and fruits may be responsible for an inverse association. The association between the consumption of 21 vegetables and nine fruits and urothelial cancer risk was assessed in the Netherlands Cohort Study among 120,852 men and women aged 55-69 years at baseline in 1986. After 6.3 years of follow-up, 538 incident cases and 2,953 subcohort members with complete vegetable data and 569 cases and 3,123 subcohort members with complete fruit data were available for case-cohort analyses. In multivariable case-cohort analyses, the following age-, sex-, and smoking-adjusted incidence rate ratios for groups of vegetable and fruit consumption were observed (comparing highest versus lowest quintile of consumption): total vegetables, 0.91 [95% confidence interval (CI): 0.65-1.27]; cooked vegetables, 0.98 (CI: 0.71-1.35); raw vegetables, 1.10 (CI: 0.78-1.53); cooked leafy vegetables, 0.89 (CI: 0.65-1.23); raw leafy vegetables, 0.94 (CI: 0.73-1.22); pulses, 1.03 (CI: 0.74-1.44); brassicas, 0.75 (CI: 0.54-1.04); allium vegetables, 0.89 (CI: 0.67-1.19); total fruit, 0.74 (CI: 0.53-1.04); and citrus fruit, 0.85 (CI: 0.62-1.17). For three separate items (cauliflower, cooked carrots, and mandarins), a statistically significant inverse association was seen, whereas for other specific vegetables or fruit, no statistically significant association was observed. The data are suggestive of an inverse association between the consumption of brassicas, total fruit, and urothelial cancer risk, whereas total vegetable consumption did not appear to be associated with urothelial cancer risk.     

Fat, fiber, fruits, vegetables, and risk of colorectal adenomas

A case-control study was conducted at the National Naval Medical Center (Maryland, USA) from 1994 to 1996 to investigate the possible association between dietary factors and colorectal adenomas. Cases (n = 239) were subjects diagnosed with adenomas (146 new and 93 recurrent) by sigmoidoscopy or colonoscopy. Those with no evidence of adenomas found by sigmoidoscopy were recruited as controls (n = 228). Dietary variables, assessed by a 100-item food frequency questionnaire, were analyzed by the logistic regression model, which was adjusted for age, gender and total energy intake. Variables of fat intake were further adjusted for red meat intake. An increased risk of 7% [odds ratio (OR): 1.07; 95% confidence interval (95% CI): 0.94-1.22] per 5% energy/day from total fat was observed. Every additional 5% unit of oleic acid intake/day significantly increased the adenoma risk by 115% (OR: 2.15; 95% CI: 1.05-4.39). Red meat fat increased the risk by 20% (OR: 1.20; 95% CI: 0.71-2.04), and white meat fat decreased the risk by 67% (OR: 0.33; 95% CI: 0.19-0.95) for every additional 5% unit of respective intake/day. Risk decreased by 41% (OR: 0.59; 95% CI: 0.41-0.86) for every additional 5% unit of fiber intake/day. Vegetable [OR per 100 g of vegetable intake/day: 0.83, 95% CI: 0.67-1.04] and fruit (OR per 100 g of fruit intake/day: 0.92, 95% CI: 0.82-1.03) intake showed an inverse association, and the results are suggestive of an association with the risk for adenomas. In conclusion, a strong positive association between oleic acid intake and colorectal adenoma risk was observed. This is likely to be an indicator of "unhealthy" food (meat, dairy, margarine, mayonnaise, sweet baked food) consumption in this population. Increased intake of dietary fiber was associated with a moderately decreased risk of adenomas.     

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.     

Intake of fruits,vegetables and selected micronutrients in relation to the risk of breast cancer

High fruit and vegetable intake has been linked with a reduced risk of breast cancer, but evidence is not consistent. We investigated the associations of breast cancer risk with vegetables, fruits and related micronutrient intake in a population-based case-control study among Chinese women in Shanghai, where dietary patterns differ substantially from other study populations. Included in the study were 1,459 incident breast cancer cases and 1,556 frequency-matched controls. Usual dietary habits were assessed by in-person interviews. Logistic regression was used to compute adjusted odds ratios (ORs) and 95% confidence intervals (CIs) to measure strength of the associations. There was no association between breast cancer risk and total vegetable intake. The risk of breast cancer declined, however, with increasing intake of dark yellow-orange vegetables (trend test, p = 0.02), Chinese white turnips (trend test, p 相似文献   

Intake of fruits, and vegetables in relation to breast cancer risk by hormone receptor status

Summary The inconsistent associations between fruit and vegetable intake and breast cancer risk may be due to heterogeneity of associations by estrogen (ER) and progesterone receptor (PR) status of the tumors. We evaluated this hypothesis in a large (2,386 cases and 2,503 controls) population-based case-control study in Poland, conducted between 2000 and 2003. We observed significant associations between reduced overall risk of breast cancer and increasing levels of total fruit intake (odds ratio (OR) for highest versus lowest quartile = 0.76, 95%CI = 0.63–0.91; p-trend = 0.01), but not for total vegetable intake (1.13 (0.93–1.37), p-trend = 0.25), after controlling for age, energy intake and known risk factors for breast cancer. The inverse association with total fruit intake was stronger for risk of ER+ (0.69 (0.54–0.88), p-trend = 0.01) than ER− tumors (0.89 (0.67–1.19), p-trend = 0.57) (p-heterogeneity = 0.02). In conclusion, this study suggests that fruit intake might have differential associations for breast tumor subtypes defined by ER status.     

Consumption of raw cruciferous vegetables is inversely associated with bladder cancer risk.

Cruciferous vegetables contain isothiocyanates, which show potent chemopreventive activity against bladder cancer in both in vitro and in vivo studies. However, previous epidemiologic studies investigating cruciferous vegetable intake and bladder cancer risk have been inconsistent. Cooking can substantially reduce or destroy isothiocyanates, and could account for study inconsistencies. In this hospital-based case-control study involving 275 individuals with incident, primary bladder cancer and 825 individuals without cancer, we examined the usual prediagnostic intake of raw and cooked cruciferous vegetables in relation to bladder cancer risk. Odds ratios (OR) and 95% confidence intervals (CI) were estimated with unconditional logistic regression, adjusting for smoking and other bladder cancer risk factors. We observed a strong and statistically significant inverse association between bladder cancer risk and raw cruciferous vegetable intake (adjusted OR for highest versus lowest category = 0.64; 95% CI, 0.42-0.97), with a significant trend (P = 0.003); there were no significant associations for fruit, total vegetables, or total cruciferous vegetables. The associations observed for total raw crucifers were also observed for individual raw crucifers. The inverse association remained significant among current and heavy smokers with three or more servings per month of raw cruciferous vegetables (adjusted ORs, 0.46 and 0.60; 95% CI, 0.23-0.93 and 0.38-0.93, respectively). These data suggest that cruciferous vegetables, when consumed raw, may reduce the risk of bladder cancer, an effect consistent with the role of dietary isothiocyanates as chemopreventive agents against bladder cancer.     

Preliminary study on the antimutagenesis of vegetables and fruits

Possible antimutation of 108 preparations of 91 kinds of vegetables and fruits on Salmonella typhimurium TA98 and TA100 mutants was tested. 4-nitroquinoline-N-oxide (4 NQO), N-methyl-N-nitro-N-nitrosoguanidine (MNNG), aflatoxin B1 (AFB1) and benzo (a) pyrene (BaP) were used as mutagens. The results showed that 67 (62%) preparations had antimutagenic action in vitro to different degrees. 9.6% of all preparations showed inhibition action on 4 NQO in TA100 mutant and 12.3%, in TA98, 5% on MNNG in TA100, 38% on AFB1 in TA100 and 45.1% in TA98, 28.9% on BaP in TA100. This experiment provides a scientific basis to the study of food resources as prevention of carcinogenesis.     

Intake of fruits and vegetables and risk of cancer of the upper aero-digestive tract: the prospective EPIC-study

Epidemiologic studies suggest that a high intake of fruits and vegetables is associated with decreased risk of cancers of the upper aero-digestive tract. We studied data from 345,904 subjects of the prospective European Investigation into Cancer and Nutrition (EPIC) recruited in seven European countries, who had completed a dietary questionnaire in 1992–1998. During 2,182,560 person years of observation 352 histologically verified incident squamous cell cancer (SCC) cases (255 males; 97 females) of the oral cavity, pharynx, larynx, and esophagus were identified. Linear and restricted cubic spline Cox regressions were fitted on variables of intake of fruits and vegetables and adjusted for potential confounders. We observed a significant inverse association with combined total fruits and vegetables intake (estimated relative risk (RR) = 0.91; 95% confidence interval (95% CI) 0.83–1.00 per 80 g/d of consumption), and nearly significant inverse associations in separate analyses with total fruits and total vegetables intake (RR: 0.97 (95% CI: 0.92–1.02) and RR = 0.89 (95% CI: 0.78–1.02) per 40 g/d of consumption). Overall, vegetable subgroups were not related to risk with the exception of intake of root vegetables in men. Restricted cubic spline regression did not improve the linear model fits except for total fruits and vegetables and total fruits with a significant decrease in risk at low intake levels (<120 g/d) for fruits. Dietary recommendations should consider the potential benefit of increasing fruits and vegetables consumption for reducing the risk of cancers of the upper aero-digestive tract, particularly at low intake. Department of Epidemiology, German Institute of Human Nutrition, Potsdam-Rehbrücke     

Satisfaction with ovarian carcinoma risk-reduction strategies among women at high risk for breast and ovarian carcinoma

BACKGROUND:

Women who are at high risk for breast and ovarian cancer have 2 major management options to reduce their risk of ovarian cancer: periodic screening (PS) or risk‐reducing salpingo‐oophorectomy (RRSO). Little is known regarding patient satisfaction levels with risk‐reduction strategies. Thus, the authors sought to determine levels of patient satisfaction with PS versus RRSO and to identify factors that may influence satisfaction.

METHODS:

As part of a larger study, women who received testing for the breast cancer genes BRCA1 and BRCA2 were sent a follow‐up questionnaire packet to explore issues related to cancer risk reduction. The authors report on the results from a variety of validated instruments, including the Satisfaction With Decision (SWD) scale, focused on the choice between PS and RRSO.

RESULTS:

In total, 544 surveys were mailed, and 313 responses were received (58%). The overall satisfaction rate among respondents was high. The median SWD score was significantly higher in the RRSO group compared with the PS group (P < .001). BRCA mutation carriers had higher median SWD scores regardless of management type (P = .01). Low satisfaction scores were associated with high levels of uncertainty and the perception that the decision between PS and RRSO was difficult to make (P = .001). Satisfaction was unrelated to demographics, clinical factors, or concerns of cancer risk.

CONCLUSIONS:

In the current study, the majority of women who were at high risk for breast and ovarian cancer were satisfied with their choice of risk‐reduction strategy. Difficulty with decision making was associated with lower satisfaction levels. Improved education and support through the decision‐making process may enhance overall levels of satisfaction. Cancer 2011. © 2010 American Cancer Society.     

Intakes of fruits, vegetables, and related nutrients and the risk of non-Hodgkin's lymphoma among women.

Non-Hodgkin's lymphoma is etiologically related to suppressed immune status, and certain nutrients found in fruits and vegetables have been associated with increased immune responses. However, limited information exists on associations between intake of fruits, vegetables, and related nutrients and non-Hodgkin's lymphoma risk. We thus examined these associations among 88,410 women in the Nurses' Health Study cohort who were aged 34-60 years in 1980 and provided dietary information in 1980. During 14 years of follow-up, we documented 199 incident cases of non-Hodgkin's lymphoma. Higher intake of fruits and vegetables was associated with a lower risk of non-Hodgkin's lymphoma (P for trend = 0.02); the multivariate relative risk (RR) was 0.62 [95% confidence interval (CI), 0.38-1.02] for women who consumed greater than or equal to six servings per day as compared with those consuming less than three servings per day. When fruits and vegetables were examined separately, intake of vegetables rather than fruits was most clearly associated with a reduced risk (P for trend = 0.02 for vegetables; P for trend = 0.16 for fruits); compared with those consuming less than one serving per day, the multivariate RRs were 0.62 (95% CI, 0.35-1.07) for women who consumed greater than or equal to three servings per day of vegetables and 0.70 (95% CI, 0.44-1.12) for women who consumed this amount of fruits. Higher intake of cruciferous vegetables was also associated with a decreased risk (P for trend = 0.03); the multivariate RR was 0.67 (95% CI, 0.40-1.11) for women who consumed greater than or equal to five servings per week as compared with those consuming less than two servings per week. These associations were slightly attenuated when we additionally adjusted for intake of beef, pork, or lamb as a main dish. Intake of dietary fiber from vegetable sources was related to a reduced risk; the multivariate RR was 0.54 (95% CI, 0.34-0.87) for women in the highest quintile as compared with those in the lowest quintile (P for trend = 0.01), and it was slightly attenuated with additional adjustment for saturated and trans unsaturated fats. However, we observed no associations between intakes of specific dietary carotenoids, vitamins A, C, E, and folate, and non-Hodgkin's lymphoma risk. Higher intake of vegetables, particularly cruciferous vegetables, may reduce the risk of non-Hodgkin's lymphoma among women.     

Intake of specific fruits and vegetables in relation to risk of estrogen receptor-negative breast cancer among postmenopausal women

In previous studies of postmenopausal women, overall intake of fruits and vegetables groups has been inversely associated with estrogen receptor-negative (ER?) breast cancer. In this analysis, we prospectively examined the associations of specific fruits and vegetables with risk of ER? postmenopausal breast cancer among 75,929 women aged 38–63 years at baseline and followed for up to 24 years. Dietary data were collected seven times during this period. Cox proportional hazard models were used, adjusting for potential confounders, including a modified Alternate Mediterranean Diet score. We ascertained 792 incident cases of ER? postmenopausal breast cancer. The multivariate relative risk (RR) for every 2 servings/week consumption for total berries was 0.82 (95 % CI = 0.71–0.96, p = 0.01), and the RR for women who consumed at least one serving of blueberries a week was 0.69 (95 % CI = 0.50–0.95, p = 0.02) compared with non-consumers. Also, the RR for consuming at least 2 servings of peaches/nectarines per week was 0.59 (95 % CI = 0.37–0.93, p = 0.02). Risk of ER? breast cancer was not associated with intakes of other specific fruits or vegetables. In conclusion, higher intake of berries and peaches was associated with lower risk of ER? breast cancer among postmenopausal women. These results are considered exploratory and need to be confirmed in further studies.     

Randomized trial with fruits and vegetables in prevention of cancer

Along with tobacco use, diet has the greatest impact on the development of human cancer. Within the broad category 'diet', the consumption of fruits and vegetables apparently plays a dominant role. Considerable efforts have been made to prove the preventive effect of different kinds of fruits and vegetables but randomized chemoprevention trials have failed to prove this presumed effectiveness of their single ingredients. The conclusive demonstration of a cancer-protective effect of a high consumption of fruits and vegetables is considered to be impractical. However, current historical changes in Europe offer a unique opportunity to conduct such a randomized trial in specific European countries. This study describes the nutritional situation and the conditions of the health system in the Baltic countries as appropriate geographic areas and demonstrates some basic design issues of the trial for three variants of outcome assumptions. A realistic assumption would be that a trial needs about 30  000 participants, an intervention period of 10 years and a subsequent follow-up time of 20 years. Annual costs could range between $5 and $10 million. A high intake of fruits and vegetables should be proven scientifically as a valid tool for cancer prevention. For a comparably short period the Baltic countries offer a time-window for a randomized trial. It is unlikely that the costs of such a trial would considerably exceed the costs of the available chemoprevention trials.     

Fruits and vegetables and ovarian cancer risk in a pooled analysis of 12 cohort studies.

Because fruits and vegetables are rich in bioactive compounds with potential cancer-preventive actions, increased consumption may reduce the risk of ovarian cancer. Evidence on the association between fruit and vegetable intake and ovarian cancer risk has not been consistent. We analyzed and pooled the primary data from 12 prospective studies in North America and Europe. Fruit and vegetable intake was measured at baseline in each study using a validated food-frequency questionnaire. To summarize the association between fruit and vegetable intake and ovarian cancer, study-specific relative risks (RR) were estimated using the Cox proportional hazards model, and then combined using a random-effects model. Among 560,441 women, 2,130 cases of invasive epithelial ovarian cancer occurred during a maximum follow-up of 7 to 22 years across studies. Total fruit intake was not associated with ovarian cancer risk-the pooled multivariate RR for the highest versus the lowest quartile of intake was 1.06 [95% confidence interval (95% CI), 0.92-1.21; P value, test for trend = 0.73; P value, test for between-studies heterogeneity = 0.74]. Similarly, results for total vegetable intake indicated no significant association (pooled multivariate RR, 0.90; 95% CI, 0.78-1.04, for the highest versus the lowest quartile; P value, test for trend = 0.06; P value, test for between-studies heterogeneity = 0.31). Intakes of botanically defined fruit and vegetable groups and individual fruits and vegetables were also not associated with ovarian cancer risk. Associations for total fruits and vegetables were similar for different histologic types. These results suggest that fruit and vegetable consumption in adulthood has no important association with the risk of ovarian cancer.     

Medication use and risk of ovarian carcinoma: a prospective study

Inflammation and gonadotropins are hypothesized to influence ovarian carcinogenesis. In a prospective study, we evaluated ovarian cancer risk associated with self-reported use of medications that influence inflammation or gonadotropin levels. The Breast Cancer Detection Demonstration Project Follow-Up Study enrolled 61,431 women in 1979 and used telephone interviews and 3 mailed questionnaires through 1998 to update risk factor information and identify incident ovarian cancers. The 1992-95 questionnaire ascertained medication use, including duration and frequency of use for aspirin, acetaminophen, other nonsteroidal anti-inflammatory drugs (NSAIDs), tranquilizers and histamine-receptor antagonists. A Poisson regression analysis generated rate ratios (RRs) and 95% confidence intervals (CIs) for the 31,364 women who were at risk of ovarian cancer and responded to the questionnaire that queried regular medication use. One hundred sixteen women developed ovarian cancer during follow-up. None of the anti-inflammatory medications was associated with ovarian cancer, but the RR for more than 1 aspirin per day for 1 year or longer was 0.56 (95% CI 0.20-1.5) and the RR for more than 5 years of regular "other NSAID" use was 2.0 (95% CI 0.95-4.2). Regular tranquilizer use was not associated with ovarian cancer, but histamine-receptor antagonists used regularly for more than 5 years (RR = 3.6, 95% CI 1.4-9.1) or more than once daily (RR = 3.1, 95% CI 1.5-6.5) appeared to increase risk. In our study, neither anti-inflammatory medications nor anti-psychotic medications were associated with ovarian cancer. Potential associations with histamine-receptor antagonists may warrant further study.     

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.     

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.     

No association between fruit,vegetables, antioxidant nutrients and risk of renal cell carcinoma

Previous epidemiologic studies that have examined the relationship between renal cell carcinoma (RCC) risk and intakes of plant foods and antioxidant nutrients have yielded inconsistent results. We therefore examined the associations between intakes of fruit, vegetables, carotenoids, flavonoids, vitamin E and vitamin C and RCC risk in the Alpha‐Tocopherol, Beta‐Carotene Cancer Prevention (ATBC) Study cohort. At baseline, 27,062 male Finnish smokers aged 50–69 years completed a 276‐item dietary questionnaire that included questions on frequency of consumption and portion size. During up to 19 years of follow‐up, 255 men developed RCC. Cox proportional hazards models were utilized to estimate relative risks (RR) and 95% confidence intervals (CI). Despite a large range in intake, no association was observed between fruit, vegetables or antioxidant nutrients and RCC risk. For example, multivariate RRs and 95% CIs for the highest versus the lowest quartile of intake were 0.79 (0.55–1.14), 1.23 (0.85–1.79), 1.09 (0.74–1.60), 0.83 (0.57–1.21), 1.09 (0.73–1.64) and 0.99 (0.67–1.46) for fruit, vegetables, total carotenoids, total flavonoids, total vitamin E and vitamin C, respectively (all p values for trend > 0.05). Our results indicate that diet may not play a large role in the etiology of RCC in male smokers, although further examination of these associations in nonsmokers, women and diverse racial populations is warranted.