Potato consumption and risk of pancreatic cancer in the HELGA cohort.

Potatoes have been a staple food in many countries throughout the years. Potatoes have a high glycaemic index (GI) score, and high GI has been associated with several chronic diseases and cancers. Still, the research on potatoes and health is scarce and contradictive, and we identified no prospective studies that had investigated the association between potatoes as a single food and the risk of pancreatic cancer. The aim of this study was to prospectively investigate the association between potato consumption and pancreatic cancer among 114 240 men and women in the prospective HELGA cohort, using Cox proportional hazard models. Information on diet (validated FFQ's), lifestyle and health was collected by means of a questionnaire, and 221 pancreatic cancer cases were identified through cancer registries. The mean follow-up time was 11·4 (95 % CI 0·3, 16·9) years. High consumption of potatoes showed a non-significantly higher risk of pancreatic cancer in the adjusted model (hazard ratio (HR) 1·44; 95 % CI 0·93, 2·22, P for trend 0·030) when comparing the highest v. the lowest quartile of potato consumption. In the sex-specific analyses, significant associations were found for females (HR 2·00; 95 % CI 1·07, 3·72, P for trend 0·020), but not for males (HR 1·01; 95 % CI 0·56, 1·84, P for trend 0·34). In addition, we explored the associations by spline regression, and the absence of dose-response effects was confirmed. In this study, high potato consumption was not consistently associated with a higher risk of pancreatic cancer. Further studies with larger populations are needed to explore the possible sex difference.

Potato Consumption and Risk of Colorectal Cancer in the Norwegian Women and Cancer Cohort.

Potatoes are the fourth most plentiful food crop in the world, yet the scientific literature on the health effects of potato consumption is scarce. This study aimed to investigate the association between potato consumption and the risk of colorectal cancer (CRC) among 79,778 women aged 41-70, in the Norwegian Women and Cancer study. Information on diet, lifestyle, and health was collected by questionnaire. CRC cases (n  =  912) were identified through registry linkage. Adjusted Cox proportional hazard models were used to estimate the association between potato consumption and the risk of CRC. Results showed that high potato consumption was associated with a higher risk of CRC (hazard ratio [HR]: 1.32, 95% confidence interval [CI]: 1.10, 1.60 for ≥3 potatoes per day versus 0-7 potatoes per week). The same association was found for rectal cancer (HR: 1.68, 95% CI: 1.19, 2.36), and same tendencies were found for colon cancer (HR: 1.20, 95% CI: 0.96, 1.50). When stratified by body mass index (BMI) (<25 and ≥25 kg/m2), significant associations were found with BMI <25 kg/m2 for CRC (HR: 1.48, 95% CI: 1.15, 1.89) and rectal cancer (HR: 1.95, 95% CI: 1.25, 3.06). No significant interaction between potato consumption and BMI (P  =  0.49) was found.

Coffee consumption and the risk of cancer in the Norwegian Women and Cancer (NOWAC) Study.

An association between coffee consumption and cancer has long been investigated. Coffee consumption among Norwegian women is high, thus this is a favorable population in which to study the impact of coffee on cancer incidence. Information on coffee consumption was collected from 91,767 women at baseline in the Norwegian Women and Cancer Study. These information were applied until follow-up information on coffee consumption, collected 6-8 years after baseline, became available. Multiple imputation was performed as a method for dealing with missing data. Multivariable Cox regression models were used to calculate hazard ratios (HR) for breast, colorectal, lung, and ovarian cancer, as well as cancer at any site. We observed a 17 % reduced risk of colorectal cancer (HR = 0.83, 95 % CI 0.70-0.98, p trend across categories of consumption = 0.10) and a 9 % reduced risk of cancer at any site (HR = 0.91, 95 % CI 0.86-0.97, p trend = 0.03) in women who drank more than 3 and up to 7 cups/day, compared to women who drank ≤1 cup/day. A significantly increased risk of lung cancer was observed with a heavy coffee consumption (>7 vs. ≤1 cup/day HR = 2.01, 95 % CI 1.47-2.75, p trend < 0.001). This was most likely caused by residual confounding due to smoking, as no statistically significant association was observed in never smokers (>5 vs. ≤1 cup/day HR = 1.42, 95 % CI 0.44-4.57, p trend = 0.30). No significant association was found between coffee consumption and the risk of breast or ovarian cancer. In this study, coffee consumption was associated with a modest reduced risk of cancer at any site. Residual confounding due to smoking may have contributed to the positive association between high coffee consumption and the risk of lung cancer.

Coffee and tea consumption and risk of pre- and postmenopausal breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study.

INTRODUCTION: Specific coffee subtypes and tea may impact risk of pre- and post-menopausal breast cancer differently. We investigated the association between coffee (total, caffeinated, decaffeinated) and tea intake and risk of breast cancer. METHODS: A total of 335,060 women participating in the European Prospective Investigation into Nutrition and Cancer (EPIC) Study, completed a dietary questionnaire from 1992 to 2000, and were followed-up until 2010 for incidence of breast cancer. Hazard ratios (HR) of breast cancer by country-specific, as well as cohort-wide categories of beverage intake were estimated. RESULTS: During an average follow-up of 11 years, 1064 premenopausal, and 9134 postmenopausal breast cancers were diagnosed. Caffeinated coffee intake was associated with lower risk of postmenopausal breast cancer: adjusted HR=0.90, 95% confidence interval (CI): 0.82 to 0.98, for high versus low consumption; Ptrend=0.029. While there was no significant effect modification by hormone receptor status (P=0.711), linear trend for lower risk of breast cancer with increasing caffeinated coffee intake was clearest for estrogen and progesterone receptor negative (ER-PR-), postmenopausal breast cancer (P=0.008). For every 100 ml increase in caffeinated coffee intake, the risk of ER-PR- breast cancer was lower by 4% (adjusted HR: 0.96, 95% CI: 0.93 to 1.00). Non-consumers of decaffeinated coffee had lower risk of postmenopausal breast cancer (adjusted HR=0.89; 95% CI: 0.80 to 0.99) compared to low consumers, without evidence of dose-response relationship (Ptrend=0.128). Exclusive decaffeinated coffee consumption was not related to postmenopausal breast cancer risk, compared to any decaffeinated-low caffeinated intake (adjusted HR=0.97; 95% CI: 0.82 to 1.14), or to no intake of any coffee (HR: 0.96; 95%: 0.82 to 1.14). Caffeinated and decaffeinated coffee were not associated with premenopausal breast cancer. Tea intake was neither associated with pre- nor post-menopausal breast cancer. CONCLUSIONS: Higher caffeinated coffee intake may be associated with lower risk of postmenopausal breast cancer. Decaffeinated coffee intake does not seem to be associated with breast cancer.

Coffee, tea and decaffeinated coffee in relation to hepatocellular carcinoma in a European population: multicentre, prospective cohort study.

Inverse associations of coffee and/or tea in relation to hepatocellular carcinoma (HCC) risk have been consistently identified in studies conducted mostly in Asia where consumption patterns of such beverages differ from Europe. In the European Prospective Investigation into Cancer and nutrition (EPIC), we identified 201 HCC cases among 486,799 men/women, after a median follow-up of 11 years. We calculated adjusted hazard ratios (HRs) for HCC incidence in relation to quintiles/categories of coffee/tea intakes. We found that increased coffee and tea intakes were consistently associated with lower HCC risk. The inverse associations were substantial, monotonic and statistically significant. Coffee consumers in the highest compared to the lowest quintile had lower HCC risk by 72% [HR: 0.28; 95% confidence intervals (CIs): 0.16-0.50, p-trend < 0.001]. The corresponding association of tea with HCC risk was 0.41 (95% CI: 0.22-0.78, p-trend = 0.003). There was no compelling evidence of heterogeneity of these associations across strata of important HCC risk factors, including hepatitis B or hepatitis C status (available in a nested case-control study). The inverse, monotonic associations of coffee intake with HCC were apparent for caffeinated (p-trend = 0.009), but not decaffeinated (p-trend = 0.45) coffee for which, however, data were available for a fraction of subjects. Results from this multicentre, European cohort study strengthen the existing evidence regarding the inverse association between coffee/tea and HCC risk. Given the apparent lack of heterogeneity of these associations by HCC risk factors and that coffee/tea are universal exposures, our results could have important implications for high HCC risk subjects.

Fish consumption and mortality in the European Prospective Investigation into Cancer and Nutrition cohort.

Fish is a source of important nutrients and may play a role in preventing heart diseases and other health outcomes. However, studies of overall mortality and cause-specific mortality related to fish consumption are inconclusive. We examined the rate of overall mortality, as well as mortality from ischaemic heart disease and cancer in relation to the intake of total fish, lean fish, and fatty fish in a large prospective cohort including ten European countries. More than 500,000 men and women completed a dietary questionnaire in 1992-1999 and were followed up for mortality until the end of 2010. 32,587 persons were reported dead since enrolment. Hazard ratios and their 99% confidence interval were estimated using Cox proportional hazard regression models. Fish consumption was examined using quintiles based on reported consumption, using moderate fish consumption (third quintile) as reference, and as continuous variables, using increments of 10 g/day. All analyses were adjusted for possible confounders. No association was seen for fish consumption and overall or cause-specific mortality for both the categorical and the continuous analyses, but there seemed to be a U-shaped trend (p < 0.000) with fatty fish consumption and total mortality and with total fish consumption and cancer mortality (p = 0.046).

Vitamin D status and PUFA ratios in a national representative cross-section of healthy, middle-aged Norwegian women­the Norwegian Women and Cancer Post-Genome Cohort.

AIMS: Vitamin D and polyunsaturated fatty acids (PUFAs) are derived from partially overlapping sources. Vitamin D is produced in the skin after sun exposure, but is also derived from fatty fish and fish oils. Dietary PUFAs are mainly derived from plant oils that are rich in n-6 PUFAs, but fatty fish provides high amounts of the marine n-3 PUFAs. The Western diet provides an excess of n-6 PUFAs compared to n-3 PUFAs, and the ratios of these may influence human health. Here, we investigated the potential associations of plasma concentrations of vitamin D, marine PUFAs and PUFA ratios. METHODS: Plasma concentrations of vitamin D (25(OH)D), marine PUFAs, and PUFA ratios were measured in 372 women from the Norwegian Women and Cancer (NOWAC) Post-Genome Cohort. Covariability was examined in 310 non-users of cod liver oil, using Spearman's rank correlation and linear regression. RESULTS: In non-users of cod liver oil, the average concentration of vitamin D was 40.3 nmol/L, and marine PUFA concentration was 0.2 mg/g. PUFA ratios were dominated by the n-6 fatty acids. Vitamin D levels were significantly associated with marine fatty acids and weakly associated with PUFA ratios. CONCLUSIONS: Concentrations of vitamin D and marine PUFAs were below recommended levels. The correlation analyses indicated that health-related effects of vitamin D and marine PUFAs respectively may be hard to separate in epidemiological studies. However, measured health effects of PUFA ratios and vitamin D are likely to derive from the influence of the two factors separately. The presented results are the first to show these associations in a nationally representative cohort.

High coffee consumption and different brewing methods in relation to postmenopausal endometrial cancer risk in the Norwegian women and cancer study: a population-based prospective study.

BACKGROUND: Coffee and its compounds have been proposed to inhibit endometrial carcinogenesis. Studies in the Norwegian population can be especially interesting due to the high coffee consumption and increasing incidence of endometrial cancer in the country. METHODS: A total of 97 926 postmenopausal Norwegian women from the population-based prospective Norwegian Women and Cancer (NOWAC) Study, were included in the present analysis. We evaluated the general association between total coffee consumption and endometrial cancer risk as well as the possible impact of brewing method. Multivariate Cox regression analysis was used to estimate risks, and heterogeneity tests were performed to compare brewing methods. RESULTS: During an average of 10.9 years of follow-up, 462 incident endometrial cancer cases were identified. After multivariate adjustment, significant risk reduction was found among participants who drank ≥8 cups/day of coffee with a hazard ratio of 0.52 (95% confidence interval, CI 0.34-0.79). However, we did not observe a significant dose-response relationship. No significant heterogeneity in risk was found when comparing filtered and boiled coffee brewing methods. A reduction in endometrial cancer risk was observed in subgroup analyses among participants who drank ≥8 cups/day and had a body mass index ≥25 kg/m2, and in current smokers. CONCLUSIONS: These data suggest that in this population with high coffee consumption, endometrial cancer risk decreases in women consuming ≥8 cups/day, independent of brewing method.

Consumption of lean fish reduces the risk of type 2 diabetes mellitus: a prospective population based cohort study of Norwegian women.

BACKGROUND: The effects of fish consumption and n-3 fatty acids on type 2 diabetes mellitus (T2DM) have recently been debated. OBJECTIVE: We explored the risk of T2DM in relation to consumption of lean fish, fatty fish, fish products and total fish as well as cod liver oil supplements in a representative sample of Norwegian women. DESIGN: This was a prospective population based cohort study in 33740 women free of T2DM, stroke, angina or heart attack and with detailed information on important co-variates and dietary intake at baseline. Risk ratios and corresponding 95% CI were estimated using Poisson regression with log-person time as offset. RESULTS: Lean fish consumption was inversely associated with T2DM compared to zero intake. Risk ratios and 95% CI for intake of 75 and 100 g lean fish per day were 0.71 (0.51, 0.98) and 0.67 (0.46, 0.98), respectively. There was no effect of intake of fatty fish, fish products, total fish or use of cod liver oil supplements on the risk of T2DM. CONCLUSION: Lean fish consumption of 75-100 g/d had a beneficial effect on T2DM. It remains unclear whether lean fish in itself has a protective effect on T2DM or that lean fish consumers have a protective life-style that we were not able to take into account in this study. Unfavorable effects of fatty fish consumption or use of cod liver oil supplements on T2DM were not observed.

Coffee and tea consumption and the risk of ovarian cancer: a prospective cohort study and updated meta-analysis.

BACKGROUND: In 2007 the World Cancer Research Fund Report concluded that there was limited and inconsistent evidence for an effect of coffee and tea consumption on the risk of epithelial ovarian cancer (EOC). OBJECTIVE: In the European Prospective Investigation into Cancer and Nutrition (EPIC), we aimed to investigate whether coffee intakes, tea intakes, or both are associated with the risk of EOC. DESIGN: All women participating in the EPIC (n = 330,849) were included in this study. Data on coffee and tea consumption were collected through validated food-frequency questionnaires at baseline. HRs and 95% CIs were estimated by using Cox proportional hazards models. Furthermore, we performed an updated meta-analysis of all previous prospective studies until April 2011 by comparing the highest and lowest coffee- and tea-consumption categories as well as by using dose-response random-effects meta-regression analyses. RESULTS: During a median follow-up of 11.7 y, 1244 women developed EOC. No association was observed between the risk of EOC and coffee consumption [HR: 1.05 (95% CI: 0.75, 1.46) for the top quintile compared with no intake] or tea consumption [HR: 1.07 (95% CI: 0.78, 1.45) for the top quintile compared with no intake]. This lack of association between coffee and tea intake and EOC risk was confirmed by the results of our meta-analysis. CONCLUSION: Epidemiologic studies do not provide sufficient evidence to support an association between coffee and tea consumption and risk of ovarian cancer.

Menopausal hormone therapy and risk of ovarian cancer in the European prospective investigation into cancer and nutrition.

The association between menopausal hormone therapy (HT) and risk of ovarian cancer was assessed among 126,920 post-menopausal women recruited into the European Prospective Investigation into Cancer and Nutrition. After an average of 9-year follow-up, 424 incident ovarian cancers were diagnosed. Cox models adjusted for body mass index, smoking status, unilateral ovariectomy, simple hysterectomy, age at menarche, number of full-term pregnancies, and duration of oral contraceptives were used. Compared with baseline never use, current use of any HT was positively associated with risk (HR [hazard ratio], 1.29; 95% CI [confidence interval], 1.01-1.65), while former use was not (HR, 0.96; 95% CI, 0.70-1.30). Current estrogen-only HT was associated with a 63% higher risk (HR, 1.63; 95% CI, 1.08-2.47), while current estrogen plus progestin was associated with a smaller and non-significant higher risk (HR, 1.20; 95% CI, 0.89-1.62). Use of tibolone was associated with a twofold greater risk (HR, 2.19; 95% CI, 1.06-4.50), but was based on small numbers. In conclusion, women who currently use HT have a moderate increased risk of ovarian cancer, and which may be stronger for estrogen-only than estrogen plus progestin preparations.

Menopausal hormone therapy and risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition.

Menopausal hormone therapy (HT) may influence colorectal cancer risk. A total of 136,275 postmenopausal women from the European Prospective Investigation into Cancer and Nutrition were followed for an average of 9 years, during which time 1,186 colorectal cancers were diagnosed. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox proportional hazards models stratified by center and age, and adjusted for body mass index, smoking, diabetes, physical activity and alcohol consumption. Compared to never use of HT at study enrollment, current use of estrogen-only (HR, 1.02; 95% CI, 0.79-1.31) or estrogen plus progestin (HR, 0.94; 95% CI, 0.77-1.14) was not significantly associated with the risk of colorectal cancer, and these associations did not vary by recency, duration, route of administration, regimen or specific constituent of HT. Our results show no significant association of estrogen-only or estrogen plus progestin therapy with colorectal cancer risk.

Menopausal hormone therapy and breast cancer risk: impact of different treatments. The European Prospective Investigation into Cancer and Nutrition.

Menopausal hormone therapy (MHT) is characterized by use of different constituents, regimens and routes of administration. We investigated the association between the use of different types of MHT and breast cancer risk in the EPIC cohort study. The analysis is based on data from 133,744 postmenopausal women. Approximately 133,744 postmenopausal women contributed to this analysis. Information on MHT was derived from country-specific self-administered questionnaires with a single baseline assessment. Incident breast cancers were identified through population cancer registries or by active follow-up (mean: 8.6 yr). Overall relative risks (RR) and 95% confidence interval (CI) were derived from country-specific Cox proportional hazard models estimates. A total of 4312 primary breast cancers were diagnosed during 1,153,747 person-years of follow-up. Compared with MHT never users, breast cancer risk was higher among current users of estrogen only (RR: 1.42, 95% CI 1.23-1.64) and higher still among current users of combined MHT (RR: 1.77, 95% CI 1.40-2.24; p = 0.02 for combined vs. estrogen-only). Continuous combined regimens conferred a 43% (95% CI: 19-72%) greater risk compared with sequential regimens. There was no significant difference between progesterone and testosterone derivatives in sequential regimens. There was no significant variation in risk linked to the estrogenic component of MHT, neither for oral vs. cutaneous administration nor for estradiol compounds vs. conjugated equine estrogens. Estrogen-only and combined MHT uses were associated with increased breast cancer risk. Continuous combined preparations were associated with the highest risk. Further studies are needed to disentangle the effects of the regimen and the progestin component.

Menopausal hormone therapy and risk of endometrial carcinoma among postmenopausal women in the European Prospective Investigation Into Cancer and Nutrition.

Estrogen-only menopausal hormone therapy (HT) increases the risk of endometrial cancer, but less is known about the association with other types of HT. Using Cox proportional hazards regression, the authors examined the association of various types of HT with the risk of endometrial cancer among 115,474 postmenopausal women recruited into the European Prospective Investigation into Cancer and Nutrition between 1992 and 2000. After a mean follow-up period of 9 years, 601 incident cases of endometrial cancer were identified. In comparison with never users of HT, risk of endometrial cancer was increased among current users of estrogen-only HT (hazard ratio (HR) = 2.52, 95% confidence interval (CI): 1.77, 3.57), tibolone (HR = 2.96, 95% CI: 1.67, 5.26), and, to a lesser extent, estrogen-plus-progestin HT (HR = 1.41, 95% CI: 1.08, 1.83), although risks differed according to regimen and type of progestin constituent. The association of HT use with risk was stronger among women who were older, leaner, or had ever smoked cigarettes. The finding of a strong increased risk of endometrial cancer with estrogen-only HT and a weaker association with combined HT supports the hypothesis that progestins have an attenuating effect on endometrial cancer risk. The increased risk associated with tibolone use requires further investigation.

The effect of coffee consumption on serum total cholesterol in the Sami and Norwegian populations.

OBJECTIVE: To assess coffee consumption in the Sami and Norwegian populations and to investigate the impact of unfiltered boiled coffee consumption on serum cholesterol concentrations. DESIGN: A cross-sectional study. Information was collected by self-administrated questionnaires and total serum cholesterol was analysed. Participants were divided into three ethnic groups: Sami I (Sami used as home language in the last three generations), Sami II (at least one Sami identity marker) and Norwegian. SETTING: In an area with Sami, Kven/Finnish and Norwegian populations, the SAMINOR study, 2003-2004. SUBJECTS: A total of 5647 men and 6347 women aged 36-79 years. RESULTS: More than 90 % of the study populations were coffee drinkers. Only 22 % were unfiltered coffee consumers. Sami I had the highest proportion of participants who consumed nine or more cups of unfiltered coffee per day, although the number of participants was limited. Total coffee consumption was associated with increased total cholesterol for men (P < 0·01) and women (P < 0·0001). For those who drank only unfiltered coffee, a significant association was found only in Norwegian men, adjusted for physical activity in leisure time, BMI and smoking habits (P < 0·001). From the lowest (less than five cups) to the highest (nine or more cups) unfiltered coffee consumption category, the mean total cholesterol levels increased by 0·29 mmol/l in Norwegian men. CONCLUSIONS: Unfiltered coffee consumption was lower in the present study compared to previous reports. In general, total coffee consumption was positively associated with total cholesterol levels. However, for unfiltered coffee consumption, an association was found only in Norwegian men.

Cod liver oil, other dietary supplements and survival among cancer patients with solid tumours.

The effect of various dietary supplements on chronic diseases and mortality has been widely studied, but few convincing results have emerged from studies in well-nourished populations. In Norway, both cod liver oil and other dietary supplements are frequently used. In the Norwegian Women and Cancer cohort study, we explored if supplement use before diagnosis affected survival of cancer patients with solid tumours. We performed Cox proportional hazards analyses, adjusting for age at diagnosis, smoking and stage. Cod liver oil was the most frequently used dietary supplement, followed by multivitamins and minerals. Whole year daily use of cod liver oil was associated with lower risk of death in patients with solid tumours [RR = 0.77 (95% CI 0.61-0.97)] and in lung cancer patients [RR=0.56 (95% CI 0.34-0.92)]. Also daily and occasional use of other dietary supplements decreased the risk of death among lung cancer patients [RR = 0.70 (95% CI 0.49-0.99) and 0.55 (95% CI 0.31-0.97)]. More research is needed to clarify the association; meanwhile adjustment for dietary supplement use should be performed in survival analyses of lung cancer patients.

Plasma phospholipid fatty acid profiles and their association with food intakes: results from a cross-sectional study within the European Prospective Investigation into Cancer and Nutrition.

BACKGROUND: Plasma phospholipid fatty acids have been correlated with food intakes in populations with homogeneous dietary patterns. However, few data are available on populations with heterogeneous dietary patterns. OBJECTIVE: The objective was to investigate whether plasma phospholipid fatty acids are suitable biomarkers of dietary intakes across populations involved in a large European multicenter study. DESIGN: A cross-sectional study design nested to the European Prospective Investigation into Cancer and Nutrition (EPIC) was conducted to determine plasma fatty acid profiles in >3,000 subjects from 16 centers, who had also completed 24-h dietary recalls and dietary questionnaires. Plasma fatty acids were assessed by capillary gas chromatography. Ecological and individual correlations were calculated between fatty acids and select food groups. RESULTS: The most important determinant of plasma fatty acids was region, which suggests that the variations across regions are largely due to different food intakes. Strong ecological correlations were observed between fish intake and long-chain n-3 polyunsaturated fatty acids (r = 0.78, P < 0.01), olive oil and oleic acid (r = 0.73, P < 0.01), and margarine and elaidic acid (r = 0.76, P < 0.01). Individual correlations varied across the regions, particularly between olive oil and oleic acid and between alcohol and the saturation index, as an indicator of stearoyl CoA desaturase activity. CONCLUSIONS: These findings indicate that specific plasma phospholipid fatty acids are suitable biomarkers of some food intakes in the EPIC Study. Moreover, these findings suggest complex interactions between alcohol intake and fatty acid metabolism, which warrants further attention in epidemiologic studies relating dietary fatty acids to alcohol-related cancers and other chronic diseases.

Plasma and dietary vitamin C levels and risk of gastric cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC-EURGAST).

Vitamin C is an antioxidant and inhibitor of carcinogenic N-nitroso compound production in the stomach. Higher dietary vitamin C consumption is associated with decreased risk of gastric cancer (GC) in numerous case-control studies, but data from prospective studies are limited, particularly so for blood measures of vitamin C. The objective of this study was to determine the association of plasma and dietary vitamin C levels with the risk of GC in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC), a large cohort involving 10 European countries. Using a fluorometric method, vitamin C was measured in pre-diagnostic plasma from 215 GC cases (matched controls = 416). Conditional logistic regression models adjusted by body mass index, total energy intake, smoking status/duration/intensity and Helicobacter pylori infection status were used to estimate relative cancer risks. No association with GC risk was observed for dietary vitamin C, whereas an inverse GC risk was observed in the highest versus lowest quartile of plasma vitamin C [odds ratio (OR) = 0.55, 95% confidence interval (CI) = 0.31-0.97, P(trend) = 0.043], which was maintained after exclusion of cases with

Fish consumption and breast cancer risk. The European Prospective Investigation into Cancer and Nutrition (EPIC).

There is current interest in fish consumption and marine omega-3 (n-3) fatty acids and breast cancer risk. Some in vitro and animal studies have suggested an inhibitory effect of marine n-3 fatty acids on breast cancer growth, but the results from epidemiological studies that have examined the association between fish consumption and breast cancer risk in humans are inconsistent. We examined fish consumption and breast cancer risk in 310,671 women aged between 25 and 70 yr at recruitment into the European Prospective Investigation Into Cancer and Nutrition (EPIC). The participants completed a dietary questionnaire between 1992-98 and were followed up for incidence of breast cancer for a median of 6.4 yr. Hazard ratio for breast cancer by intake of total and lean and fatty fish were estimated, stratified by study centre and adjusted for established breast cancer risk factors. During follow-up, 4,776 invasive incident breast cancers were reported. No significant associations between intake of total fish and breast cancer risk were observed, hazard ratio (HR) 1.01 (95% confidence interval [CI] 0.99-1.02; p = 0.28 per 10 g fish/day). When examining lean and fatty fish separately, we found a positive significant association only in the highest quintile for fatty fish (HR 1.13, 95% CI 1.01-1.26), but test for trend was not significant (p = 0.10). No associations with breast cancer risk were observed when the study participants were subdivided by menopausal status. Although the period of follow-up is relatively short, the results provide no evidence for an association between fish intake and breast cancer risk.

A pooled analysis of case-control studies of thyroid cancer: cigarette smoking and consumption of alcohol, coffee, and tea.

OBJECTIVE: To analyze the role of smoking, alcohol, coffee and tea in relation to thyroid cancer, we conducted a pooled analysis of 14 case-control studies conducted in the United States, Europe, and Asia. METHODS: The sample consisted of 2725 thyroid cancer cases (2247 females, 478 males) and 4776 controls (3699 females, 1077 males). Conditional logistic regression with stratification on study, age at diagnosis, and gender was used to compute odds ratios and 95% confidence intervals. RESULTS: Thyroid cancer risk was reduced in persons who had ever smoked. The relationship was more pronounced in current smokers (OR = 0.6, 95% CI = 0.6-0.7) than former smokers (OR = 0.9, 95% CI = 0.8-1.1). There were significant trends of reduced risk with greater duration and frequency of smoking. For consumption of wine and beer, there was a significant trend of decreasing thyroid cancer risk (p = 0.02) that was not maintained after adjustment for current smoking (p = 0.12). Thyroid cancer risk was not associated with consumption of coffee or tea. These findings were consistent in both gender-specific and histology-specific (papillary and follicular) analyses. CONCLUSIONS: Pooled analyses of these geographically diverse case-control data indicate a reduced thyroid cancer risk associated with current smoking. A reduced risk associated with alcohol was eliminated after adjustment for smoking, and caffeinated beverages did not alter thyroid cancer risk.