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Sustainable diets are gaining interest as a possible approach to tackle climate change and the global extent of obesity. Yet, the association between sustainable diets and adiposity remains unclear. We performed a systematic review and meta-analysis, calculating summary relative risks and 95% confidence intervals (CI). We pooled maximally adjusted risk estimates, assessed heterogeneity and publication bias, calculated the E-value, and evaluated the risk of bias across the included studies. A total of eight studies were eligible for analysis. Comparing the highest versus the lowest levels of adherence to sustainable diets, the pooled effect estimate was 0.69 (95% CI = 0.62-0.76) for overweight and 0.61 (95% CI = 0.47-0.78) for obesity. These results suggest that sustainable diets may decrease the risk of overweight/obesity and therefore could serve as enablers for improving both public and planetary health. An agreed-upon clear definition of sustainable diets would enhance the comparability of future studies in this area., (© 2024 The Authors. Obesity Reviews published by John Wiley & Sons Ltd on behalf of World Obesity Federation.)

CVD is the most common chronic condition and the highest cause of mortality in the USA. The aim of the present work was to investigate diet and sedentary behaviour in relation to mortality in US CVD survivors. The National Health and Nutrition Examination Surveys conducted between 1999 and 2014 linked to the US mortality registry updated to 2015 were investigated. Multivariate adjusted Cox regression was used to derive mortality hazards in relation to sedentary behaviour and nutrient intake. A multiplicative and additive interaction analysis was conducted to evaluate how sedentariness and diet influence mortality in US CVD survivors. A sample of 2473 participants followed for a median period of 5·6 years resulted in 761 deaths, and 199 deaths were due to CVD. A monotone increasing relationship between time spent in sedentary activities and mortality risk was observed for all-cause and CVD mortality (hazard ratio (HR) = 1·20, 95 % CI 1·09, 1·31 and HR = 1·19, 95 % CI 1·00, 1·67, respectively). Inverse mortality risks in the range of 22-34 % were observed when comparing the highest with the lowest tertile of dietary fibre, vitamin A, carotene, riboflavin and vitamin C. Sedentariness below 360 min/d and dietary fibre and vitamin intake above the median interact on an additive scale influencing positively all-cause and CVD mortality risk. Reduced sedentariness in combination with a varied diet rich in dietary fibre and vitamins appears to be a useful strategy to reduce all-cause and CVD mortality in US CVD survivors.

Background & Aims: Cancer is the second most common chronic disease and cause of death in the United States. Our aim was to evaluate the associations of sedentary behavior and nutrient intakes with total and cancer-specific mortality among US cancer survivors., Methods: Data from 2371 cancer survivors collected by the US National Health and Nutrition Examination Survey between 1999 and 2014 were linked to the US mortality registry. Multivariable adjusted Cox proportional hazard models were used to estimate the hazard ratios (HR) and 95% confidence intervals (CI) for all-cause and cancer-specific mortality associated with sedentary time and nutrient intakes. The interaction between time spent on sedentary activities and nutrient intake was evaluated on additive and multiplicative scales., Results: During a median observational period of 5.7 years, 532 total deaths occurred among cancer survivors, of which 180 were cancer-specific. A monotonic increasing linear relationship between time spent sitting and all-cause mortality was observed (HR = 1.15, 95% CI = 1.03, 1.28 per one standard deviation increment). The highest versus the lowest tertiles of intakes of dietary fiber, carotene, niacin, thiamine, riboflavin, vitamin B6, vitamin B12, and vitamin C were inversely associated with all-cause and cancer-specific mortality (HRs = 0.48 to 0.75). The inverse associations with all-cause mortality were more pronounced for combinations of low sedentary behaviour and high intakes of dietary fiber, carotenoids, vitamin B12, and vitamin C., Conclusion: Our findings support recommendations for cancer survivors to reduce time spent sedentary and to follow a balanced diet with adequate intakes of dietary fiber and micronutrients., (Copyright © 2020 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Background: Previously we showed that adulthood body mass index (BMI) trajectories that result in obesity were associated with elevated risks of fatal prostate cancer (PCA). To further explore this relationship, we conducted a study within the NIH-AARP Diet and Health Study., Methods: Among 153 730 eligible men enrolled in the NIH-AARP cohort from 1995 to 1996 (median follow-up = 15.1 years), we identified 630 fatal PCA cases and 16 896 incident cases. BMI was assessed for ages 18, 35 and 50 and at study entry, enabling examination of latent class-identified BMI trajectories. Hazard ratios (HRs) and 95% confidence intervals (CI) were estimated using Cox proportional hazards regression., Results: BMI at study entry (mean age = 63, HR = 1.12; 95% CI = 1.01, 1.24, per 5-unit increase) and maximum BMI during adulthood (HR = 1.12; 95% CI = 1.02, 1.24, per 5-unit increase) shared modest associations with increased risk of fatal PCA. Smoking status likely modified the relationship between BMI trajectories and fatal PCA (Pinteraction = 0.035 via change-in-estimate variable section, P = 0.065 via full a priori model). Among never-smokers, BMI trajectory of normal weight to obesity was associated with increased risk of fatal disease (HR = 2.37; 95% CI = 1.38, 4.09), compared with the maintained normal weight trajectory, whereas there was no association among former or current-smokers. Total and non-aggressive PCA exhibited modest inverse associations with BMI at all ages, whereas no association was observed for aggressive PCA., Conclusions: Increased BMI was positively associated with fatal PCA, especially among never-smokers. Future studies that examine PCA survival will provide additional insight as to whether these associations are the result of biology or confounding., (Published by Oxford University Press on behalf of the International Epidemiological Association 2018. This work is written by US Government employees and is in the public domain in the US.)

Very large international and ethnic differences in cancer rates exist, are minimally explained by genetic factors, and show the huge potential for cancer prevention. A substantial portion of the differences in cancer rates can be explained by modifiable factors, and many important relationships have been documented between diet, physical activity, and obesity, and incidence of important cancers. Other related factors, such as the microbiome and the metabolome, are emerging as important intermediary components in cancer prevention. It is possible with the incorporation of newer technologies and studies including long follow-up and evaluation of effects across the life cycle, additional convincing results will be produced. However, several challenges exist for cancer researchers; for example, measurement of diet and physical activity, and lack of standardization of samples for microbiome collection, and validation of metabolomic studies. The United States National Cancer Institute convened the Research Strategies for Nutritional and Physical Activity Epidemiology and Cancer Prevention Workshop on June 28-29, 2016, in Rockville, Maryland, during which the experts addressed the state of the science and areas of emphasis. This current paper reflects the state of the science and priorities for future research. Cancer Epidemiol Biomarkers Prev; 27(3); 233-44. ©2017 AACR ., (©2017 American Association for Cancer Research.)

Despite a potential preventive effect of physical activity on hepatobiliary cancer, little information is available on the relation between the two. We studied the association between frequency of vigorous physical activity and hepatobiliary cancer among 507,897 participants of the NIH-AARP Diet and Health Study, aged 50-71 years at baseline in 1995/1996. During 10 years of follow-up, 628 incident cases of liver cancer and 317 cases of extrahepatic biliary tract cancer were registered. Physical activity levels were assigned according to the frequency of engagement in 20 min or more of vigorous physical activity per week: never/rarely (lowest level), less than once per week, 1-2 times per week, 3-4 times per week, 5 or more times per week (highest level). Using Cox regression, multivariate-adjusted relative risks (RR) comparing the highest with the lowest level of physical activity revealed a statistically significant decreased risk for liver cancer (RR = 0.64, 95% confidence interval (CI) = 0.49-0.84, p-trend <0.001), particularly hepatocellular carcinoma (RR = 0.56, 95% CI = 0.41-0.78, p-trend <0.001), independent of body mass index. By comparison, multivariate analyses indicated that physical activity was not statistically significantly associated with extrahepatic bile duct cancer (RR = 0.86, 95% CI = 0.45-1.65), ampulla of Vater cancer (RR = 0.66, 95% CI = 0.29-1.48), or gallbladder cancer (RR = 0.63, 95% CI = 0.33-1.21). These results suggest a potential preventive effect of physical activity on liver cancer but not extrahepatic biliary tract cancer, independent of body mass index.

Little is known about the association between alcohol and breast cancer by different tumor characteristics. The study consisted of 184,418 postmenopausal women aged 50-71 years in the National Institutes of Health-AARP Diet and Health Study (1995-2003). Alcohol use, diet, and potential risk factors for cancer were assessed with a mailed questionnaire at baseline. The relative risks and 95% confidence intervals were estimated by using Cox proportional hazards regression. Breast cancer cases and estrogen receptor and progesterone receptor status were identified through linkage to state cancer registries. During an average of 7 years of follow-up, 5,461 breast cancer cases were identified. Alcohol was significantly positively associated with total breast cancer: Even a moderate amount of alcohol (>10 g/day) significantly increased breast cancer risk. In a comparison of >35 g versus 0 g/day, the multivariate relative risks were 1.35 (95% confidence interval (CI): 1.17, 1.56) for total breast cancer, 1.46 (95% CI: 1.22, 1.75) for ductal tumors, and 1.52 (95% CI: 0.95, 2.44) for lobular tumors. The multivariate relative risks for estrogen receptor-positive/progesterone receptor-positive, estrogen receptor-positive/progesterone receptor-negative, and estrogen receptor-negative/progesterone receptor-negative tumors were 1.46 (95% CI: 1.12, 1.91) for >35 g versus 0 g/day, 1.13 (95% CI: 0.73, 1.77) for >20 g versus 0 g/day, and 1.21 (95% CI: 0.79, 1.84) for >20 g versus 0 g/day, respectively. Moderate consumption of alcohol was associated with breast cancer, specifically hormone receptor-positive tumors.

Recommendations for intake of fruits and vegetables, whole grains, lean meats, and low-fat dairy form the underpinning of dietary guidance for health promotion. We examined the association of a summary index of food consumption behaviors compatible with the spirit of prevailing dietary guidance and mortality. We used data from the NIH-American Association of Retired Persons cohort (n = 350,886), aged 50-71 y and disease free at baseline in 1995-1996, to examine the association of a dietary behavior score (DBS) with mortality after 10.5 y of follow-up (deaths, n = 29,838). The DBS included 6 equally weighted components derived from responses to questions on usual dietary behaviors related to consumption of fruits, vegetables, low-fat dairy, whole grains, lean meat and poultry, and discretionary fat. The covariate-adjusted association of DBS and mortality from all causes, cancer, and coronary heart disease was examined using Cox proportional hazards regression methods. Compared with those in the lowest one-fifth of DBS, the multivariate-adjusted relative risk of mortality in the highest one-fifth of the DBS was 0.75 (95% CI, 0.70-0.80) in women and 0.79 (95% CI, 0.75-0.83) in men (P-trend < 0.0001). The inverse association of DBS and mortality was significant in both genders in nearly all categories of covariates. Similar trends were observed for DBS associations with mortality from cancer and heart disease. Nearly 12% of the covariate-adjusted population risk of mortality was attributable to nonconformity with dietary recommendations. Adoption of recommended dietary behaviors was associated with lower mortality in both men and women independent of other lifestyle risk factors.

Fruit and vegetable consumption has been hypothesized to reduce the risk of renal cell cancer. We conducted a pooled analysis of 13 prospective studies, including 1,478 incident cases of renal cell cancer (709 women and 769 men) among 530,469 women and 244,483 men followed for up to 7 to 20 years. Participants completed a validated food-frequency questionnaire at baseline. Using the primary data from each study, the study-specific relative risks (RR) were calculated using the Cox proportional hazards model and then pooled using a random effects model. We found that fruit and vegetable consumption was associated with a reduced risk of renal cell cancer. Compared with <200 g/d of fruit and vegetable intake, the pooled multivariate RR for >or=600 g/d was 0.68 [95% confidence interval (95% CI) = 0.54-0.87; P for between-studies heterogeneity = 0.86; P for trend = 0.001]. Compared with <100 g/d, the pooled multivariate RRs (95% CI) for >or=400 g/d were 0.79 (0.63-0.99; P for trend = 0.03) for total fruit and 0.72 (0.48-1.08; P for trend = 0.07) for total vegetables. For specific carotenoids, the pooled multivariate RRs (95% CIs) comparing the highest and lowest quintiles were 0.87 (0.73-1.03) for alpha-carotene, 0.82 (0.69-0.98) for beta-carotene, 0.86 (0.73-1.01) for beta-cryptoxanthin, 0.82 (0.64-1.06) for lutein/zeaxanthin, and 1.13 (0.95-1.34) for lycopene. In conclusion, increasing fruit and vegetable consumption is associated with decreasing risk of renal cell cancer; carotenoids present in fruit and vegetables may partly contribute to this protection.

Consistent with a strong hormonal etiology, endometrial cancer is thought to be influenced by both obesity and physical activity. Although obesity has been consistently related to risk, associations with physical activity have been inconclusive. We examined relationships of activity patterns with endometrial cancer incidence in the NIH-AARP Diet and Health Study cohort, which included 109,621 women, ages 50-71, without cancer history, who in 1995-1996 completed a mailed baseline questionnaire capturing daily routine and vigorous (defined as any period of >or=20 min of activity at work or home causing increases in breathing, heart rate, or sweating) physical activity. A second questionnaire, completed by 70,351 women, in 1996-1997 collected additional physical activity information. State cancer registry linkage identified 1,052 primary incident endometrial cancers from baseline through December 31, 2003. In multivariate proportional hazards models, vigorous activity was inversely associated with endometrial cancer in a dose-response manner (p for trend = 0.02) (relative risk (RR) for >or=5 times/week vs. never/rarely = 0.77, 95% confidence interval (CI): 0.63-0.95); this association was more pronounced among overweight and obese women (body mass index >or=25; RR = 0.61, 95% CI: 0.47-0.79) than among lean women (body mass index <25; RR = 0.76, 95% CI: 0.52-1.10; p for interaction = 0.12). Although we observed no associations with light/moderate, daily routine or occupational physical activities, risk did increase with number of hours of daily sitting (p for trend = 0.02). Associations with vigorous activities, which may interact with body mass index, suggest directions for future research to clarify underlying biologic mechanisms, including those relating to hormonal alterations., ((c) 2008 Wiley-Liss, Inc.)

Background: High intakes of red or processed meat may increase the risk of mortality. Our objective was to determine the relations of red, white, and processed meat intakes to risk for total and cause-specific mortality., Methods: The study population included the National Institutes of Health-AARP (formerly known as the American Association of Retired Persons) Diet and Health Study cohort of half a million people aged 50 to 71 years at baseline. Meat intake was estimated from a food frequency questionnaire administered at baseline. Cox proportional hazards regression models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) within quintiles of meat intake. The covariates included in the models were age, education, marital status, family history of cancer (yes/no) (cancer mortality only), race, body mass index, 31-level smoking history, physical activity, energy intake, alcohol intake, vitamin supplement use, fruit consumption, vegetable consumption, and menopausal hormone therapy among women. Main outcome measures included total mortality and deaths due to cancer, cardiovascular disease, injuries and sudden deaths, and all other causes., Results: There were 47 976 male deaths and 23 276 female deaths during 10 years of follow-up. Men and women in the highest vs lowest quintile of red (HR, 1.31 [95% CI, 1.27-1.35], and HR, 1.36 [95% CI, 1.30-1.43], respectively) and processed meat (HR, 1.16 [95% CI, 1.12-1.20], and HR, 1.25 [95% CI, 1.20-1.31], respectively) intakes had elevated risks for overall mortality. Regarding cause-specific mortality, men and women had elevated risks for cancer mortality for red (HR, 1.22 [95% CI, 1.16-1.29], and HR, 1.20 [95% CI, 1.12-1.30], respectively) and processed meat (HR, 1.12 [95% CI, 1.06-1.19], and HR, 1.11 [95% CI 1.04-1.19], respectively) intakes. Furthermore, cardiovascular disease risk was elevated for men and women in the highest quintile of red (HR, 1.27 [95% CI, 1.20-1.35], and HR, 1.50 [95% CI, 1.37-1.65], respectively) and processed meat (HR, 1.09 [95% CI, 1.03-1.15], and HR, 1.38 [95% CI, 1.26-1.51], respectively) intakes. When comparing the highest with the lowest quintile of white meat intake, there was an inverse association for total mortality and cancer mortality, as well as all other deaths for both men and women., Conclusion: Red and processed meat intakes were associated with modest increases in total mortality, cancer mortality, and cardiovascular disease mortality.

Previous studies have provided limited evidence for a harmful effect of high glycemic index and dietary glycemic load on cancer. The authors analyzed associations among glycemic index, glycemic load, and risk of cancer in women and men in the National Institutes of Health-AARP Diet and Health Study. Published glycemic index values were assigned to 225 foods/food groups. Glycemic load was calculated by multiplying the glycemic index, carbohydrate content, and intake frequency of individual foods reported on a food frequency questionnaire. From 1995 through 2003, the authors identified 15,215 and 33,203 cancer cases in women and men, respectively. Cox proportional hazards models were used to estimate multivariate relative risks and 95% confidence intervals. For women and men, respectively, the relative risks for total cancer for high versus low glycemic index were 1.03 (P(trend)=0.217) and 1.04 (P(trend)=0.012) and, for glycemic load, were 0.90 (P(trend)=0.024) and 0.93 (P(trend)=0.01). Associations with total cancer held only among the overweight for glycemic index and among those of healthy weight for glycemic load. These findings suggest that glycemic index and glycemic load are not strong predictors of cancer incidence. The direction and small magnitude of associations might be explained by the manner in which high glycemic index and glycemic load track with overall diet and lifestyle patterns.

Increased fruit and vegetable consumption may protect against lung cancer, although epidemiologic findings are inconclusive. The authors prospectively examined associations between lung cancer risk and intakes of fruit, vegetables, and botanical subgroups in 472,081 participants aged 50-71 years in the National Institutes of Health (NIH)-AARP Diet and Health Study. Diet was assessed at baseline (1995-1996) with a 124-item dietary questionnaire. A total of 6,035 incident lung cancer cases were identified between 1995 and 2003. Total fruit and vegetable intake was unrelated to lung cancer risk in both men and women. Higher consumption of several botanical subgroups, however, was significantly inversely associated with risk, but only in men. For example, the relative risks of lung cancer among men in the highest versus lowest quintiles of intake of rosaceae, convolvulaceae, and umbelliferae were 0.82 (95% confidence interval (CI): 0.73, 0.91), 0.86 (95% CI: 0.75, 0.96), and 0.86 (95% CI: 0.78, 0.96), respectively; corresponding relative risks in women were 0.97 (95% CI: 0.85, 1.12), 0.95 (95% CI: 0.83, 1.09), and 0.92 (95% CI: 0.80, 1.06). These results provide support for a protective role of specific botanical subgroups of fruits and vegetables in lung cancer prevention in men, although the findings could also be due to residual confounding by smoking or chance.

Background: Although it has been hypothesized that hyperglycemia, hyperinsulinemia, and insulin resistance are involved in the development of pancreatic cancer, results from epidemiologic studies of added sugar intake are inconclusive., Objective: Our objective was to investigate whether the consumption of total added sugar and sugar-sweetened foods and beverages is associated with pancreatic cancer risk., Design: In 1995 and 1996, we prospectively examined 487 922 men and women aged 50-71 y and free of cancer and diabetes. Total added dietary sugar intake (in tsp/d; based on the US Department of Agriculture's Pyramid Servings Database) was assessed with a food-frequency questionnaire. Relative risks (RRs) and 95% CIs were calculated with adjustment for total energy and potential confounding factors., Results: During an average 7.2 y of follow-up, 1258 incident pancreatic cancer cases were ascertained. The median intakes for the lowest and highest quintiles of total added sugar intake were 12.6 (3 tsp/d) and 96.2 (22.9 tsp/d) g/d, respectively. No overall greater risk of pancreatic cancer was observed in men or women with high intake of total added sugar or sugar-sweetened foods and beverages. For men and women combined, the multivariate RRs of the highest versus lowest intake categories were 0.85 (95% CI: 0.68, 1.06; P for trend = 0.07) for total added sugar, 1.01 (0.82,1.23; P for trend = 0.58) for sweets, 0.98 (0.82,1.18; P for trend = 0.49) for dairy desserts, 1.12 (0.91,1.39; P for trend = 0.35) for sugar added to coffee and tea, and 1.01 (0.77,1.31; P for trend = 0.76) for regular soft drinks., Conclusion: Our results do not support the hypothesis that consumption of added sugar or of sugar-sweetened foods and beverages is associated with overall risk of pancreatic cancer.

Background: Various saturated fatty acids have different effects on blood lipids and insulin secretion in experiments. The effect of long-term consumption of specific and different classes of saturated fatty acids on the risk of gallstone disease in humans is unknown., Methods: We prospectively studied consumption of saturated fatty acids and risk of gallstone disease in a cohort of 44,524 US men from 1986 to 2002. Intake of saturated fatty acids was assessed using a validated semiquantitative food frequency questionnaire. Newly diagnosed gallstone disease was ascertained biennially., Results: During 584,679 person-years of follow-up, we documented 2350 incident cases of gallstone disease, of which 1387 cases required cholecystectomy. Compared with men in the lowest quintile of dietary intake of long-chain saturated fats, after adjustment for age and other potential risk factors, the relative risk of gallstone disease for men in the highest quintile was 1.24 [95% confidence interval (CI), 1.02, 1.50, P for trend = 0.03], and the relative risk of cholecystectomy for men in the highest quintile was 1.41 (CI, 1.09, 1.82, P for trend = 0.008). Consumption of medium-chain saturated fatty acids or short-chain saturated fatty acids was unrelated to the risk., Conclusions: Our results suggest that a higher consumption of long-chain saturated fatty acids may enhance the risk of gallstone disease in men.

Higher intakes of calcium and dairy products, a major source of dietary calcium, are reported to increase the risk of prostate cancer, potentially due to reductions in circulating vitamin D with increasing calcium intake. We prospectively examined the association of dairy product and calcium intake with prostate cancer risk in 29,509 men, including 1,910 cases, in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. We also evaluated the relation of calcium intake with serum 25-hydroxy-vitamin D [25(OH)D] and 1,25-dihydroxy-vitamin D [1,25(OH)(2)D], in a Prostate, Lung, Colorectal, and Ovarian Trial substudy (n = 275). Dietary intake was assessed using a food frequency questionnaire. Baseline serum 1,25(OH)(2)D was determined by RIA. Greater intake of dairy products, particularly low-fat dairy products, was weakly associated with increased risk of prostate cancer [relative risk (RR), 1.12; 95% confidence intervals (CI), 0.97-1.30; P trend = 0.06 for >2.75 versus < or = 0.98 servings of total dairy/day; 1.23 (1.07-1.41) for low-fat dairy]. Greater dietary calcium intake was associated with increased risk of prostate cancer (RR, 1.34; 95% CI, 0.93-1.94; P trend = 0.02 for >2,000 versus <1,000 mg/day), but greater supplementary calcium intake was not associated with the risk. Associations of dairy product and dietary calcium intake were evident for nonaggressive disease (RR, 1.20; 95% CI, 0.99-1.46; P trend = 0.01 for dairy products; 1.64, 1.04-2.57; P trend = 0.002 for dietary calcium), but not aggressive disease (RR, 1.02; 95% CI, 0.81-1.28 for dairy products; 0.94, 0.49-1.80 for dietary calcium). Calcium intake was not associated with serum 25-hydroxy-vitamin D and 1,25(OH)(2)D concentration. In this large prospective study in a prostate cancer screening trial, greater dietary intake of calcium and dairy products, particularly low-fat types, may be modestly associated with increased risks for nonaggressive prostate cancer, but was unrelated to aggressive disease. Furthermore, we found no relationship between calcium intake and circulating vitamin D.

Supplemental vitamin E (alpha-tocopherol) has been linked to lower prostate cancer incidence in one randomized trial and several, although not all, observational studies. The evidence regarding dietary intake of individual vitamin E isoforms and prostate cancer is limited and inconclusive, however. We prospectively examined the relations of supplemental vitamin E and dietary intakes of alpha-, beta-, gamma-, and delta- tocopherols to prostate cancer risk among 295,344 men, ages 50 to 71 years and cancer-free at enrollment in 1995 to 1996, in the NIH-AARP Diet and Health Study. At baseline, participants completed a questionnaire that captured information on diet, supplement use, and other factors. Proportional hazards models were used to estimate relative risks (RR) and 95% confidence intervals (95% CI) of prostate cancer. During 5 years of follow-up, 10,241 incident prostate cancers were identified. Supplemental vitamin E intake was not related to prostate cancer risk (for >0-99, 100-199, 200-399, 400-799, and > or = 800 IU/d versus never use: RR, 0.97, 0.89, 1.03, 0.99, and 0.97 (95% CI, 0.87-1.07) respectively; Ptrend = 0.90). However, dietary gamma-tocopherol, the most commonly consumed form of vitamin E in the United States, was significantly inversely related to the risk of advanced prostate cancer (for highest versus lowest quintile: RR, 0.68; 95% CI, 0.56-0.84; Ptrend = 0.001). These results suggest that supplemental vitamin E does not protect against prostate cancer, but that increased consumption of gamma-tocopherol from foods is associated with a reduced risk of clinically relevant disease. The potential benefit of gamma-tocopherol for prostate cancer prevention deserves further attention.

Background: Whether the intake of dietary fiber can protect against colorectal cancer is a long-standing question of considerable public health import, but the epidemiologic evidence has been inconsistent., Objective: The objective was to investigate the relation between dietary fiber and whole-grain food intakes and invasive colorectal cancer in the prospective National Institutes of Health-AARP Diet and Health Study., Design: The analytic cohort consisted of 291 988 men and 197 623 women aged 50-71 y. Diet was assessed with a self-administered food-frequency questionnaire at baseline in 1995-1996; 2974 incident colorectal cancer cases were identified during 5 y of follow-up. The Cox proportional hazards model was used to estimate the relative risks (RRs) and 95% CIs., Results: Total dietary fiber intake was not associated with colorectal cancer. The multivariate RR for the highest compared with the lowest intake quintile (RR(Q5-Q1)) was 0.99 (95% CI: 0.85, 1.15; P for trend = 0.96). In analyses of fiber from different food sources, only fiber from grains was associated with a lower risk of colorectal cancer (multivariate RR(Q5-Q1): 0.86; 95% CI: 0.76, 0.98; P for trend = 0.01). Whole-grain intake was inversely associated with colorectal cancer risk: the multivariate RR(Q5-Q1) was 0.79 (95% CI: 0.70, 0.89) for the whole cohort (P for trend < 0.001). The association with whole grain was stronger for rectal than for colon cancer., Conclusions: In this large prospective cohort study, total dietary fiber intake was not associated with colorectal cancer risk, whereas whole-grain consumption was associated with a modest reduced risk.

Purpose: Many constituents of fruits and vegetables may reduce the risk for gallstones, but prospective data relating fruit and vegetable intake to gallstone disease are sparse., Methods: We prospectively studied fruit and vegetable consumption in relation to the risk of cholecystectomy in a cohort of 77,090 women in the Nurses' Health Study, 37 to 64 years of age, who had no history of gallstone disease. Women reported on follow-up questionnaires both their consumption of fruits and vegetables and whether they had undergone cholecystectomy., Results: During 1,060,033 person-years of follow-up from 1984 to 2000, participants reported 6608 cases of cholecystectomy. After adjusting for established or suspected risk factors, the relative risk for women in the highest quintile of overall consumption of fruits and vegetables was 0.79 (95% confidence interval [CI], 0.73-0.87, P for trend<.0001) compared with those in the lowest quintile. Similar results were seen for both total fruits and total vegetables separately. The composite items of fruits and vegetables including green leafy vegetables, citrus fruits, vitamin C-rich fruits and vegetables, and cruciferous vegetables also were each inversely associated with the risk., Conclusions: Our findings suggest a protective role of greater fruit and vegetable consumption against risk of cholecystectomy in women.

With the growing number of epidemiologic publications on the relation between dietary factors and cancer risk, pooled analyses that summarize results from multiple studies are becoming more common. Here, the authors describe the methods being used to summarize data on diet-cancer associations within the ongoing Pooling Project of Prospective Studies of Diet and Cancer, begun in 1991. In the Pooling Project, the primary data from prospective cohort studies meeting prespecified inclusion criteria are analyzed using standardized criteria for modeling of exposure, confounding, and outcome variables. In addition to evaluating main exposure-disease associations, analyses are also conducted to evaluate whether exposure-disease associations are modified by other dietary and nondietary factors or vary among population subgroups or particular cancer subtypes. Study-specific relative risks are calculated using the Cox proportional hazards model and then pooled using a random- or mixed-effects model. The study-specific estimates are weighted by the inverse of their variances in forming summary estimates. Most of the methods used in the Pooling Project may be adapted for examining associations with dietary and nondietary factors in pooled analyses of case-control studies or case-control and cohort studies combined.

Objectives: We examined post-diagnostic diet and risk of cancer progression in a cohort of men with prostate cancer from the Health Professionals Follow-up Study., Methods: We observed 392 progression outcomes among 1,202 men diagnosed with incident localized/regional prostate cancer between 1986 and 1996. Men completed prospective dietary surveys before and after diagnosis and were followed through 2000. We examined post-diagnostic consumption of red meat, grains, vegetables, fruits, milk, tomatoes, tomato sauce, and fish as predictors of progression using Cox proportional hazard regression models adjusted for total energy, age, clinical factors, and pre-diagnostic diet., Results: Men in the highest versus lowest quartile of post-diagnostic fish consumption had a multivariate hazard ratio (HR) of progression of 0.73 (95% CI 0.52-1.02); the comparable HR for tomato sauce was 0.56 (95% CI 0.38-0.82). We observed inverse linear relationships for fish and tomato sauce and risk of progression (HR = 0.83, p-value = 0.006 and HR = 0.80, p-value = 0.04 for a two serving/week increase of fish and tomato sauce, respectively). Milk and fresh tomato consumption were associated with small elevations in risk., Conclusions: These data suggest that diet after diagnosis may influence the clinical course of prostate cancer, and fish and tomato sauce may offer some protection against disease progression.

Background: The consumption of trans-fatty acids adversely affects blood lipid levels. The relationship with the incidence of gallstone disease is unknown., Methods: We prospectively studied consumption of trans-fatty acids in relation to the risk of gallstone disease in a cohort of 45,912 men. trans-Fatty acid consumption was assessed using a validated semiquantitative food frequency questionnaire. Newly diagnosed gallstone disease, by radiology or cholecystectomy, was ascertained biennially., Results: During 14 years of follow-up, we documented 2356 new cases of symptomatic gallstones. After adjusting for age and other potential risk factors, we found that compared with men in the lowest quintile of dietary intake of trans-fatty acids, the relative risk (RR) of gallstone disease for those in the highest quintile was 1.23 (95% confidence interval [CI], 1.04-1.44; P for trend, .03). Among individual trans-fatty acids, the RR for trans-oleic fatty acid, when extreme quintiles were compared, was 1.24 (95% CI, 1.06-1.45; P for trend, .02). Intakes of trans-palmitoleic fatty acid (RR, 1.09; 95% CI, 0.90-1.31), trans,trans 18:2 fatty acid (RR, 1.14; 95% CI, 0.96-1.34), and cis-trans 18:2 fatty acid (RR, 1.00; 95% CI, 0.86-1.16) were not significantly associated with the risk., Conclusions: Our results suggest that a higher intake of trans-fatty acids modestly increases risk of gallstone disease. This adds to the concern that partial hydrogenation of vegetable oils to form shortening and margarine can lead to adverse health effects.

Gallstone disease is a major source of morbidity in Western countries. Nuts are rich in several compounds that may be protective against gallstones. The objective of the study was to examine the relation between nut consumption and gallstone disease in the Health Professionals Follow-up Study. The consumption of nuts was assessed starting in 1986 as part of a 131-item semiquantitative food frequency questionnaire. The main outcome measure was newly diagnosed symptomatic gallstones. During 457,305 person-years of follow-up, 1,833 participants reported gallstone disease. After adjustment for age and other known or suspected risk factors, men consuming 5 or more units of nuts per week (frequent consumption) had a significantly lower risk of gallstone disease (relative risk = 0.70, 95% confidence interval: 0.60, 0.86; p(trend) < 0.001) than did men who never ate or who ate less than 1 unit per month (rare consumption) (1 unit = 1 ounce (0.028 kg) of nuts). Further adjustment for fat consumption (saturated fat, trans-fat, polyunsaturated fat, and monounsaturated fat) did not materially alter the relation. In analyses examining consumption of peanuts and other nuts separately, both were significantly associated with a lower risk of gallstone disease in the age-adjusted and multivariate models. Our findings suggest that frequent nut consumption is associated with a reduced risk of gallstone disease in men.

Background: Gallstone disease is a major source of morbidity in the developed countries. Nuts are rich in several compounds that may protect against gallstone disease., Objective: The association between nut intake and cholecystectomy was examined in a large cohort of women., Design: We prospectively studied nut (peanuts, other nuts, and peanut butter) consumption in relation to the risk of cholecystectomy in a cohort of 80,718 women from the Nurses' Health Study who were 30-55 y old in 1980 and had no history of gallstone disease. As part of the Nurses' Health Study, the women reported on questionnaires mailed to them every 2 y both their consumption of nuts and whether they had undergone cholecystectomy. The women were followed through 2000., Results: During 1,393,256 person-years of follow-up from 1980 to 2000, we documented 7831 cholecystectomies. After adjustment for age and other known or suspected risk factors, women who consumed > or =5 units of nuts (1 unit = 1 oz or 28.6 g nuts)/wk (frequent consumption) had a significantly lower risk of cholecystectomy (relative risk: 0.75; 95% CI: 0.66, 0.85; P for trend < 0.0001) than did women who never ate nuts or who ate <1 unit/mo (rare consumption). Further adjustment for fat consumption (saturated fat, trans fat, polyunsaturated fat, and monounsaturated fat) did not materially alter the relation. In analyses examining consumption of peanuts and other nuts separately, both were associated with a lower risk of cholecystectomy., Conclusion: In women, frequent nut consumption is associated with a reduced risk of cholecystectomy.

Experimental studies suggest that marine fatty acids have an antitumor effect on prostate tumor cells. The aim of this study was to investigate whether high consumption of fish and marine fatty acids reduces the risk of prostate cancer in humans. We followed 47882 men participating in the Health Professionals Follow-up Study. Dietary intake was assessed in 1986, 1990, and 1994, using a validated food frequency questionnaire. During 12 years of follow-up, 2482 cases of prostate cancer were diagnosed, of which 617 were diagnosed as advanced prostate cancer including 278 metastatic prostate cancers. Eating fish more than three times per week was associated with a reduced risk of prostate cancer, and the strongest association was for metastatic cancer (multivariate relative risk, 0.56; 95% confidence interval, 0.37-0.86, compared with infrequent consumption, i.e., less than twice per month). Intake of marine fatty acids from food showed a similar but weaker association. Each additional daily intake of 0.5 g of marine fatty acid from food was associated with a 24% decreased risk of metastatic cancer. We found that men with high consumption of fish had a lower risk of prostate cancer, especially for metastatic cancer. Marine fatty acids may account for part of the effect, but other factors in fish may also play a role.