Dietary patterns and the risk of postmenopausal breast cancer

Dietary patterns derived with multiple methods from food diaries and breast cancer risk in the UK Dietary Cohort Consortium

BACKGROUND/OBJECTIVES

In spite of several studies relating dietary patterns to breast cancer risk, evidence so far remains inconsistent. This study aimed to investigate associations of dietary patterns derived with three different methods with breast cancer risk.

SUBJECTS/METHODS

The Mediterranean Diet Score (MDS), principal components analyses (PCA) and reduced rank regression (RRR) were used to derive dietary patterns in a case-control study of 610 breast cancer cases and 1891 matched controls within four UK cohort studies. Dietary intakes were collected prospectively using 4- to 7-day food diaries and resulting food consumption data were grouped into 42 food groups. Conditional logistic regression models were used to estimate odds ratios (ORs) for associations between pattern scores and breast cancer risk adjusting for relevant covariates. A separate model was fitted for post-menopausal women only.

RESULTS

The MDS was not associated with breast cancer risk (OR comparing first tertile with third 1.20 (95% CI 0.92; 1.56)), nor the first PCA-derived dietary pattern, explaining 2.7% of variation of diet and characterized by cheese, crisps and savoury snacks, legumes, nuts and seeds (OR 1.18 (95% CI 0.91; 1.53)). The first RRR-derived pattern, a 'high-alcohol' pattern, was associated with a higher risk of breast cancer (OR 1.27; 95% CI 1.00; 1.62), which was most pronounced in post-menopausal women (OR 1.46 (95% CI 1.08; 1.98)).

CONCLUSIONS

A 'high-alcohol' dietary pattern derived with RRR was associated with an increased breast cancer risk; no evidence of associations of other dietary patterns with breast cancer risk was observed in this study.

Nutritional and unhealthy behaviors in women with and without breast cancer

Background:

Breast cancer is the most common malignancy in women. Global statistics indicate increasing rates of this cancer. Nutrition, diet, and healthy behaviors are among influential factors in prevalence of breast cancer, and possibly affect its incidence through inflammatory and immune system responses.

Objectives:

This study was designed to compare nutritional and unhealthy behaviors in women with and without breast cancer referred to Mahdieh Imaging Center in Hamadan in 2013.

Patients and Methods:

This cross-sectional study is conducted on 232 women with r and without breast cancer referred to Mahdieh Imaging Center of Hamadan, Iran) in 2013 using random sampling method. Data were collected using nutritional and unhealthy behaviors questionnaires, and analyzed with SPSS-17 software using descriptive statistics and Mann-Whitney, independent t, and chi-square tests.

Results:

The mean scores of feeding type in the patients with and without breast cancer was 56.14 and 66.25, respectively. Results obtained from data analysis showed that there was statistically significant difference between the two groups in terms of nutrition (P < 0.001), but no relationship was observed between breast cancer and unhealthy behaviors.

Conclusions:

Given the results, improving skills, training and awareness is necessary for women and emphasis on modified diet is recommended as a non-medical option for prevention of breast cancer.

Consumption of sweet foods and mammographic breast density: a cross-sectional study

BACKGROUND

The increasing consumption of sugar worldwide seems to lead to several health problems, including some types of cancer. While some studies reported a positive association between sweet foods intake and breast cancer risk, little is known about their relation to mammographic density (MD), a strong breast cancer risk factor. This study examined the association of sweet foods and drinks intake with MD among 776 premenopausal and 779 postmenopausal women recruited at mammography.

METHODS

A food-frequency questionnaire was used to assess intake of sweet foods, sugar-sweetened beverages and spoonsful of sugar added. Percent and absolute breast density were estimated using a computer-assisted method. Multivariate generalized linear models were used to evaluate associations. All models were adjusted for potential confounders, including age and body mass index.

RESULTS

For increasing quartiles of sugar-sweetened beverages intake, adjusted-mean absolute density was respectively 32, 34, 32 and 36 cm2 among all women (P(trend) = 0.040) and 43, 46, 44 and 51 cm2 among premenopausal women (P(trend) = 0.007). For increasing quartiles of sweet foods intake, adjusted-mean percent density was respectively 16, 16, 17 and 19% among postmenopausal women (P(trend) = 0.036). No association was shown between intake of spoonsful of sugar added and MD.

CONCLUSION

Our results suggest that an increase in sweet foods or sugar-sweetened beverage intake is associated with higher MD.

Dietary patterns and breast cancer risk among women

OBJECTIVE

Breast cancer is the most common type of cancer in women worldwide. Several studies have examined the role of single nutrients and food groups in breast cancer pathogenesis but fewer investigations have addressed the role of dietary patterns. Our main objective was to identify the relationship between major dietary patterns and breast cancer risk among Iranian women.

DESIGN

Hospital-based case-control study.

SETTING

Shohada Teaching Hospital, Tehran, Iran.

SUBJECTS

Overall, 100 female patients aged 30-65 years with breast cancer and 174 female hospital controls were included in the present study. Dietary intake was assessed using a valid and reliable semi-quantitative FFQ consisting of 168 food items.

RESULTS

Two dietary patterns were identified explaining 24·31 % of dietary variation in the study population. The 'healthy' food pattern was characterized by the consumption of vegetables, fruits, low-fat dairy products, legumes, olive and vegetable oils, fish, condiments, organ meat, poultry, pickles, soya and whole grains; while the 'unhealthy' food pattern was characterized by the consumption of soft drinks, sugars, tea and coffee, French fries and potato chips, salt, sweets and desserts, hydrogenated fats, nuts, industrial juice, refined grains, and red and processed meat. Compared with the lowest tertile, women in the highest tertile of the 'healthy' dietary pattern score had 75 % decreased risk of breast cancer (OR = 0·25, 95 % CI 0·08, 0·78), whereas women in the highest tertile of the 'unhealthy' dietary pattern had a significantly increased breast cancer risk (OR = 7·78, 95 % CI 2·31, 26·22).

CONCLUSIONS

A healthy dietary pattern may be negatively associated with breast cancer risk, while an unhealthy dietary pattern is likely to increase the risk among Iranian women.

Red meat consumption is associated with an increased overall cancer risk: a prospective cohort study in Korea

Cancer is a leading cause of death, and the dietary pattern in Korea is changing rapidly from a traditional Korean diet to a Westernised diet. In the present study, we investigated the effects of dietary factors on cancer risk with a prospective cohort study. Among 26 815 individuals who participated in cancer screening examinations from September 2004 to December 2008, 8024 subjects who completed a self-administered questionnaire concerning demographic and lifestyle factors, and a 3 d food record were selected. As of September 2013, 387 cancer cases were identified from the National Cancer Registry System, and the remaining individuals were included in the control group. The hazard ratio (HR) of cancer for the subjects older than or equal to 50 years of age was higher (HR 1·80, 95 % CI 1·41, 2·31; P< 0·0001) than that for the other subjects. Red meat consumption, Na intake and obesity (BMI ≥ 25 kg/m2) were positively associated with overall cancer incidence in men (HR 1·41, 95 % CI 1·02, 1·94; P= 0·0382), gastric cancer (HR 2·34, 95 % CI 1·06, 5·19; P= 0·0365) and thyroid cancer (HR 1·56, 95 % CI 1·05, 2·31; P= 0·0270), respectively. Participants who had at least three dietary risk factors among the high intakes of red meat and Na, low intakes of vegetables and fruits, and obesity suggested by the World Cancer Research Fund/American Institute for Cancer Research at baseline tended to have a higher risk of cancer than the others (HR 1·26, 95 % CI 0·99, 1·60; P= 0·0653). In summary, high intakes of red meat and Na were significant risk factors of cancer among Koreans.

Mediterranean diet and mortality in Switzerland: an alpine paradox?

PURPOSE

Reports on the protective effect of a Mediterranean diet on mortality usually refer to populations from Mediterranean countries, leaving uncertain whether really diet is the fundamental cause. Our aim was to examine the effect of a Mediterranean diet on mortality in Switzerland, a country combining cultural influences from Mediterranean and Central European countries within a common national health and statistical registry.

METHODS

In this prospective investigation, we included 17,861 men and women aged ≥16 years who participated 1977-1993 in health studies and were followed up for survival until 2008 by anonymous record linkage with the Swiss National Cohort. A 9-point score Mediterranean Diet Score (MDS) was used to assess adherence to a Mediterranean diet. Mortality hazard ratios (HR) and 95% confidence intervals (CIs) were calculated by using Cox regression models adjusted for age, sex, survey wave, marital status, smoking, body mass index, language region and nationality.

RESULTS

In all language regions, MDS was inversely associated with mortality. Consumption of dairy products was also consistently associated with lower mortality. When categorizing dairy food consumption as beneficial instead of harmful, this association between MDS and mortality increased in strength and was partly statistically significant. For all causes of death combined (HR for a one-point increase in MDS 0.96, 95% CI 0.94-0.98), in men (0.94, 0.92-0.97), in women (0.98, 0.95-1.02) for cardiovascular diseases (CVD, 0.96, 0.92-0.99; 0.95, 0.90-1.00; 0.98, 0.92-1.04) and for cancer (0.95, 0.92-0.99; 0.92, 0.88-0.97; 0.98, 0.93-1.04).

CONCLUSIONS

Stronger adherence to a Mediterranean diet was associated with lower all-cause, CVD and cancer mortality, largely independently of cultural background. These associations were primary due to the effect in men. Our finding of a beneficial rather than a deleterious impact of dairy products consumption prompts at considering culturally adapted Mediterranean diet recommendations. However, results should be interpreted with caution since only a crude 1-day dietary estimate was available to assess individuals' habitual dietary intake.

3D models of human ERα and ERβ complexed with coumestrol

Coumestrol, a phytoestrogen found in alfalfa, clover, and beans, has nM affinity for both estrogen receptor-α [ERα] and ERβ. Recently, a novel activity of coumestrol was reported: coumestrol binding to human ERβ represses microglia-mediated inflammation, which is associated with various neurodegenerative diseases, such as multiple sclerosis. In contrast, estradiol binding to ERβ had little or no effect on repression of microglia-mediated inflammation. Coumestrol and estradiol have several structural differences, which suggest that each ligand could induce different conformations in ERβ and, thus, different transcriptional responses in brain microglia. To begin to understand how coumestrol binds to ERβ and ERα, we constructed 3D models of coumestrol with human ERβ and ERα, which were compared to the structures of these ERs with estradiol. Of four possible orientations of coumestrol in ERα and ERβ, one orientation had the most favorable contacts with both ERs. Other phytochemicals may activate ERβ and inhibit inflammation in brain microglia and be useful therapeutics for inflammatory conditions in the brain.

Breast cancer and dietary patterns: a systematic review

This systematic review collates research on the topic of dietary patterns and breast cancer risks. The literature search targeted epidemiological studies published up to December 2012 and was conducted using the Medline (U.S. National Library of Medicine, Bethesda MD, USA) and Lilacs (Latin American and Caribbean Health Sciences, São Paulo, Brazil) databases. The following search terms were used: breast cancer, breast neoplasm, breast carcinoma, diet, food, eating habits, dietary patterns, factor analysis, and principal component analysis. Only studies that used factor analysis techniques and/or principal component analysis were eligible, and a total of 26 studies were included. The findings of these studies suggest the Mediterranean dietary pattern and diets composed largely of vegetables, fruit, fish, and soy are associated with a decreased risk of breast cancer. There was no evidence of an association between traditional dietary patterns and risk of breast cancer, and only one study showed a significant increase in risk associated with the Western dietary pattern. Diets that include alcoholic beverages may be associated with increased risk.

Dietary patterns and breast cancer risk in the California Teachers Study cohort

BACKGROUND

Evidence that diet is associated with breast cancer risk is inconsistent. Most studies have examined risks associated with specific foods and nutrients, rather than measures of overall diet.

OBJECTIVE

This study aimed to evaluate dietary patterns and their relation to breast cancer risk in a large cohort of women.

DESIGN

Data from 91,779 women in the California Teachers Study cohort were analyzed, including data from 4140 women with a diagnosis of invasive breast cancer made between 1995 and 2009. Five predominant dietary patterns were identified by using principal components factor analysis: a plant-based diet, high in fruit and vegetables; a high-protein, high-fat diet, high in meats, eggs, fried foods, and high-fat condiments; a high-carbohydrate diet, high in convenience foods, pasta, and bread products; an ethnic diet, high in legumes, soy-based foods, rice, and dark-green leafy vegetables; and a salad and wine diet, high in lettuce, fish, wine, low-fat salad dressing, and coffee and tea.

RESULTS

The plant-based pattern was associated with a reduction in breast cancer risk (RR: 0.85; 95% CI: 0.76, 0.95 for the highest compared with the lowest consumption quintile; P-trend = 0.003); risk reduction was greater for estrogen receptor-negative progesterone receptor-negative (ER-PR-) tumors (RR: 0.66; 95% CI: 0.48, 0.91; P-trend = 0.03). The salad and wine pattern was associated with an increased risk of estrogen receptor-positive progesterone receptor-positive tumors (RR: 1.29; 95% CI: 1.12, 1.49); this effect was only slightly attenuated after adjustment for alcohol consumption.

CONCLUSION

The finding that greater consumption of a plant-based dietary pattern is associated with a reduced breast cancer risk, particularly for ER-PR- tumors, offers a potential avenue for prevention.

Prospective study on long-term dietary patterns and incident depression in middle-aged and older women

BACKGROUND

Although individual nutrients have been investigated in relation to depression risk, little is known about the overall role of diet in depression.

OBJECTIVE

We examined whether long-term dietary patterns derived from a food-frequency questionnaire (FFQ) predict the development of depression in middle-aged and older women.

DESIGN

We conducted a prospective study in 50,605 participants (age range: 50-77 y) without depression in the Nurses' Health Study at baseline (1996) who were followed until 2008. Long-term diet was assessed by using FFQs every 4 y since 1986. Prudent (high in vegetables) and Western (high in meats) patterns were identified by using a principal component analysis. We used 2 definitions for clinical depression as follows: a strict definition that required both a reported clinical diagnosis and use of antidepressants (3002 incident cases) and a broad definition that further included women who reported either a clinical diagnosis or antidepressant use (7413 incident cases).

RESULTS

After adjustment for age, body mass index, and other potential confounders, no significant association was shown between the diet patterns and depression risk under the strict definition. Under the broad definition, women with the highest scores for the Western pattern had 15% higher risk of depression (95% CI: 1.04, 1.27; P-trend = 0.01) than did women with the lowest scores, but after additional adjustment for psychological scores at baseline, results were no longer significant (RR: 1.09; 95% CI: 0.99, 1.21; P-trend = 0.08).

CONCLUSION

Overall, results of this large prospective study do not support a clear association between dietary patterns from factor analysis and depression risk.

Traditional dietary pattern of South America is linked to breast cancer: an ongoing case-control study in Argentina

INTRODUCTION

Several studies have shown the effect of dietary patterns on breast cancer risk, but none has been conducted in Argentina. The aim of this study was to extract dietary patterns from Food Frequency Questioner, to estimate their effect on breast cancer occurrence while taking into account aggregation factors (family history of breast cancer) and to explore the sensitivity of the estimates to changes in the assumptions.

METHODS

A principal component exploratory factor analysis was applied to identify dietary patterns, which were then included as covariates in a multilevel logistic regression. Family history of BC was considered as a clustering variable. A multiple probabilistic sensitivity analysis was also performed.

RESULTS

The study included 100 cases and 294 controls. Four dietary patterns were identified. Traditional (fat meats, bakery products, and vegetable oil and mayonnaise) (OR III tertile vs I 3.13, 95% CI 2.58-3.78), Rural (processed meat) (OR III tertile vs I 2.02, 95% CI 1.21-3.37) and Starchy (refined grains) (OR III tertile vs I 1.82, 95 % CI 1.18-2.79) dietary patterns were positively associated with BC risk, whereas the Prudent pattern (fruit and non-starchy vegetables) (OR III tertile vs I 0.56, 95% CI 0.41-0.77) showed a protective effect. For Traditional pattern, the median bias-adjusted ORs (3.52) were higher than the conventional (2.76).

CONCLUSIONS

While the Prudent pattern was associated with a reduced risk of BC, Traditional, Rural and Starchy patterns showed a promoting effect. Despite the threats to validity, the nature of associations was not strongly affected.

Evaluating and adapting the Mediterranean diet for non-Mediterranean populations: a critical appraisal

This review outlines the limitations of current techniques for evaluating the Mediterranean diet in Mediterranean versus non-Mediterranean populations. Differences between the two populations with regard to the foods that are available, food processing and preparation techniques, and eating and lifestyle habits may influence the implementation and effects of a Mediterranean diet in non-Mediterranean regions. For example, the composition of food groups may vary significantly, due to differences in the specific foods within a food group and to differences in aspects of food production and preparation. Notable differences between the diets of Mediterranean versus non-Mediterranean populations include the source of monounsaturated fatty acids (olive oil versus meat), the amount of vegetables consumed and their manner of preparation, the source of alcohol (wine versus other) and the pattern of intake, and the types of meat and dairy products consumed. Lifestyle factors such as meal patterns and exposure to sunlight may also act as confounding factors when the overall benefits of a Mediterranean diet are assessed. Improving the calculation of Mediterranean diet scores and measuring plasma nutrient levels may help mitigate the effects of confounders. These considerations could have important health implications when a Mediterranean diet is implemented by non-Mediterranean populations.

Adherence to WCRF/AICR cancer prevention recommendations and risk of postmenopausal breast cancer

BACKGROUND

In 2007, the World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR) released eight recommendations related to body fatness, physical activity, and diet aimed at preventing the most common cancers worldwide. However, limited information exists on the association between meeting these recommendations and risks of specific cancers, including breast cancer.

METHODS

We operationalized six recommendations (related to body fatness, physical activity, foods that promote weight gain, plant foods, red and processed meats, and alcohol) and examined their association with invasive breast cancer incidence over 6.7 years of follow-up in the Vitamins and Lifestyle (VITAL) study cohort. Participants included 30,797 postmenopausal women, ages 50-76 years at baseline in 2000-2002 with no history of breast cancer. Breast cancers (n = 899) were tracked through the Western Washington Surveillance, Epidemiology, and End Results database.

RESULTS

Breast cancer risk was reduced by 60% in women who met at least five recommendations compared with those who met none [HR: 0.40; 95% confidence interval (CI): 0.25-0.65; Ptrend < 0.001]. Further analyses that sequentially removed individual recommendations least associated with reduced risk suggested that this reduction is due to meeting recommendations related to body fatness, plant foods, and alcohol (HR for meeting vs. not meeting these three recommendations: 0.38; 95% CI: 0.25-0.58; Ptrend < 0.001).

CONCLUSIONS

Meeting the WCRF/AICR cancer prevention recommendations, specifically those related to alcohol, body fatness, and plant foods, is associated with reduced postmenopausal breast cancer incidence.

IMPACT

Increased adherence to the WCRF/AICR cancer prevention recommendations could substantially reduce postmenopausal breast cancer risk in U.S. women.

Risk factors for premenopausal breast cancer: a case-control study in Uruguay

In order to thoroughly analyze risk factors of breast cancer (BC) in premenopausal Uruguayan women, a case-control study was carried out at the Pereira Rossell Women's Hospital, Montevideo, where 253 incident BC cases and 497 frequency-matched healthy controls were interviewed on menstrual and reproductive story, were administered a short food frequency questionnaire and undertook a series of body measurements necessary to calculate body composition and somatotype. Odds ratio (OR) coefficients were taken as estimates of relative risk derived from unconditional logistic regression. Among the classical risk factors, only the family history of BC in first degree relatives was significantly associated with risk of premenopausal BC (OR=2.20, 95% CI 1.33-3.62). Interestingly, this risk factor was found to be stronger in women of ages >40 (OR=4.05, 95% CI 2.10-7.81), late menarche (OR= 2.39, 95% CI 1.18-4.85), early age for their first delivery (OR=3.02, 95% CI 1.26-7.22), short time between menarche and first delivery (OR=3.22, 95% CI 1.29-8.07), and with high parity (OR=4.10, 95% CI 1.79-9.36), although heterogeneity was detected only for age and parity. High consumption of red meat was positively associated with the disease risk (OR=2.20, 95% CI 1.35-3.60), in the same way as fried foods (OR=1.79, 95% CI 1.12-2.84). Conversely, a high intake of plant foods displayed a protective effect (OR=0.41, 95% CI 0.26-0.65). Except for hypertension (OR=1.55, 95% CI 1.03-2.35), none of the analyzed components of metabolic syndrome were associated to BC risk. Particular increases of risk for premenopausal BC were found for family history in first degree relatives in certain subsets derived from the menstrual-reproductive history. Preventive strategies could broaden their scope if new studies confirm the present results, in view of the limited prevention measures that premenopausal BC currently has.

Fruit and vegetable intake and risk of breast cancer by hormone receptor status

BACKGROUND

Estrogen receptor-negative (ER(-)) breast cancer has few known or modifiable risk factors. Because ER(-) tumors account for only 15% to 20% of breast cancers, large pooled analyses are necessary to evaluate precisely the suspected inverse association between fruit and vegetable intake and risk of ER(-) breast cancer.

METHODS

Among 993 466 women followed for 11 to 20 years in 20 cohort studies, we documented 19 869 estrogen receptor positive (ER(+)) and 4821 ER(-) breast cancers. We calculated study-specific multivariable relative risks (RRs) and 95% confidence intervals (CIs) using Cox proportional hazards regression analyses and then combined them using a random-effects model. All statistical tests were two-sided.

RESULTS

Total fruit and vegetable intake was statistically significantly inversely associated with risk of ER(-) breast cancer but not with risk of breast cancer overall or of ER(+) tumors. The inverse association for ER(-) tumors was observed primarily for vegetable consumption. The pooled relative risks comparing the highest vs lowest quintile of total vegetable consumption were 0.82 (95% CI = 0.74 to 0.90) for ER(-) breast cancer and 1.04 (95% CI = 0.97 to 1.11) for ER(+) breast cancer (P (common-effects) by ER status < .001). Total fruit consumption was non-statistically significantly associated with risk of ER(-) breast cancer (pooled multivariable RR comparing the highest vs lowest quintile = 0.94, 95% CI = 0.85 to 1.04).

CONCLUSIONS

We observed no association between total fruit and vegetable intake and risk of overall breast cancer. However, vegetable consumption was inversely associated with risk of ER(-) breast cancer in our large pooled analyses.

Current evidence on healthy eating

Large nutritional epidemiology studies, with long-term follow-up to assess major clinical end points, coupled with advances in basic science and clinical trials, have led to important improvements in our understanding of nutrition in primary prevention of chronic disease. Although much work remains, sufficient evidence has accrued to provide solid advice on healthy eating. Good data now support the benefits of diets that are rich in plant sources of fats and protein, fish, nuts, whole grains, and fruits and vegetables; that avoid partially hydrogenated fats; and that limit red meat and refined carbohydrates. The simplistic advice to reduce all fat, or all carbohydrates, has not stood the test of science; strong evidence supports the need to consider fat and carbohydrate quality and different protein sources. This article briefly summarizes major findings from recent years bearing on these issues.

The inhibition of early stages of HER-2/neu-mediated mammary carcinogenesis by dietary n-3 PUFAs

SCOPE

We previously demonstrated that lifelong feeding of diets enriched in n-3 fatty acids such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) significantly inhibits HER-2/neu-mediated mammary tumorigenesis in mice. Of interest is whether dietary n-3 fatty acids exert effects at early stages of mammary carcinogenesis.

METHODS AND RESULTS

Seven-week-old female MMTV-HER-2/neu transgenic mice were randomized to AIN-based semipurified diets containing either fish or corn oil at 25% energy. Mice were evaluated at 25, 30, and 35 weeks with analysis of mammary glands for atypical ductal hyperplasia (hematoxylin and eosin), cell proliferation (Ki67 immunostaining), and fatty acid synthase and cyclooxygenase-2 gene expression (qRT-PCR). Tissue fatty acid profiles were quantitated by GC. Atypia grade decreased significantly in mice fed fish oil (p = 0.002). Mammary epithelial cells in mammary glands from mice fed fish oil also had an eightfold lower percentage of Ki67 expression. COX-2 expression in mammary fat-pads significantly decreased in mice fed fish versus corn oil enriched diets.

CONCLUSION

Dietary fish oil inhibits atypical ductal hyperplasia at early stages of HER-2/neu-mediated mammary carcinogenesis relative to corn oil diets. This histologic change is associated with suppression of mammary epithelial cell proliferation and decreased COX-2 expression in mammary tissue.

Fruits, vegetables and breast cancer risk: a systematic review and meta-analysis of prospective studies

Evidence for an association between fruit and vegetable intake and breast cancer risk is inconclusive. To clarify the association, we conducted a systematic review and meta-analysis of the evidence from prospective studies. We searched PubMed for prospective studies of fruit and vegetable intake and breast cancer risk until April 30, 2011. We included fifteen prospective studies that reported relative risk estimates and 95 % confidence intervals (CIs) of breast cancer associated with fruit and vegetable intake. Random effects models were used to estimate summary relative risks. The summary relative risk (RR) for the highest versus the lowest intake was 0.89 (95 % CI: 0.80-0.99, I (2) = 0 %) for fruits and vegetables combined, 0.92 (95 % CI: 0.86-0.98, I (2) = 9 %) for fruits, and 0.99 (95 % CI: 0.92-1.06, I (2) = 20 %) for vegetables. In dose-response analyses, the summary RR per 200 g/day was 0.96 (95 % CI: 0.93-1.00, I (2) = 2 %) for fruits and vegetables combined, 0.94 (95 % CI: 0.89-1.00, I (2) = 39 %) for fruits, and 1.00 (95 % CI: 0.95-1.06, I (2) = 17 %) for vegetables. In this meta-analysis of prospective studies, high intake of fruits, and fruits and vegetables combined, but not vegetables, is associated with a weak reduction in risk of breast cancer.

Methodological aspects of the study of dietary patterns during pregnancy and maternal and infant health outcomes. A systematic review

The objective of the present study was to systematically review the literature exploring the associations between different dietary patterns obtained from Food Frequency Questionnaires during pregnancy and the development of health-related maternal and infant outcomes in the Framework of the EURRECA Network of Excellence. A systematic search was conducted on Pubmed for literature published up to September 2009. The search strategy resulted in an initial amount of 2048 articles. After applying the selection criteria, seven studies were finally identified. Five articles were based on prospective cohort studies and the other two were case-control studies. The methods used to elaborate the dietary pattern could be classified as hypothesis-oriented (three studies) or empirically-derived (four studies). The different food frequency questionnaires used for diet assessment were self-administered, semi-quantitative and had been previously validated, but just four studies employed questionnaires validated specifically for their use in a pregnant population. The divergent methods used to assess the dietary patterns make it difficult to compare results. However, some resulting recommendations can be applied when dietary patterns during pregnancy are analyzed: to employ a validated food frequency questionnaire designed for use in pregnancy, to consider the special role exerted by mineral and vitamin supplements in this particular population group, to adequately select the time in which dietary data is collected, to adjust the results for life-style and educational characteristics, and in the case of hypothesis-oriented dietary patterns, to correctly choose the components comprising the score.

Update on the relationship of fish intake with prostate, breast, and colorectal cancers

A systematic review of prospective cohort and case-control studies investigating relationships between the intake of fish and incidence of prostate, breast, or colorectal cancers was conducted. A total of 106 studies fulfilled the requirements stated in the "Search strategy and selection criteria." Among 273 estimates of association reported by these studies, 53 indicated decreased risk while 12 indicated increased risk associated with fish intake. The hypothesis linking fish consumption and low cancer incidence appears to be supported by little epidemiological data. However, there are several factors that may mask potential protective associations with fish intake. The type and the amount of fish eaten, the cooking method, the stage of the cancer and, amongst women, menopausal status may all be important factors that relate to whether fish is protective or not. Future epidemiologic studies with a clearer assessment of these factors are needed to know more about the effects of fish consumption on cancer risk. Therefore, until there are better measures of dietary exposure or biomarkers to correlate self-report, no conclusion can be drawn regarding the recommendation for increasing fish consumption in general to reduce the risk of developing the most common cancers in Western societies.

Diet quality is related to eating competence in cross-sectional sample of low-income females surveyed in Pennsylvania

Women participants of two federally administered nutrition education programs (n=149, 56% white, 64% food secure, 86% 18-50 years of age,) completed telephone interviews that included three 24-hour dietary recalls and the Satter Eating Competence Inventory. Eating competence is delineated by an Inventory score≥32. Competent eaters had significantly greater intakes of fiber, vitamin A, vitamin E, vitamin C, most B-vitamins, magnesium, iron, zinc, potassium and a higher Healthy Eating Index. Two dietary patterns defined as Prudent and Western were observed. The Prudent pattern was correlated with eating competence and characterized by more healthful foods such as fruits, vegetables and low-fat dairy products. The Western pattern, characterized by foods higher in fat, salt, and sugar, was not related to eating competence. Findings suggest that dietary guidance using an eating competence approach for low-income women is compatible with goals to improve dietary quality and eating patterns.

Diets and hormonal levels in postmenopausal women with or without breast cancer

The role of diet in breast cancer (BC) risk is unclear. Fiber could reduce BC risk, through the enterohepatic circulation of estrogens. We examined the relationship between diet and sex hormones in postmenopausal women with or without BC. Thirty-one postmenopausal women (10 omnivores, 11 vegetarians, and 10 BC omnivores) were recruited. Dietary records (5 days) and hormone levels (3 days) were evaluated on 4 occasions over 1 yr. Vegetarians showed a lower fat/fiber ratio, a higher intake of total and cereal fiber (g/d)/body weight (kg), a significantly lower level of plasma estrone-sulfate, estradiol, free-estradiol, free-testosterone, and ring D oxygenated estrogens, and a significantly higher level of sex-hormone-binding-globulin than BC subjects. Fiber was consumed in slightly larger amounts by omnivores than by BC subjects. Omnivores had significantly lower plasma testosterone and estrone-sulfate but higher sex-hormone-binding-globulin than BC subjects. No difference was found for the urinary 16-oxygenated estrogens. However, the 2-MeO-E1/2-OH-E1 ratio was significantly lower in omnivores than in BC group. This ratio is positively associated with the fat/fiber ratio. In conclusion, testosterone may contribute to causing alterations in the levels of catechol estrogens and 16-oxygenated estrogens. The fat/fiber ratio appears to be useful in evaluating dietary effects on estrogen metabolism.

The association between body shape silhouette and dietary pattern among Mexican women

Objective

To investigate the relationship between dietary patterns and self-perceived body shape silhouette and BMI in a sample of Mexican women.

Design

A cross-sectional analysis of dietary habits from baseline data of a large cohort study (EsMaestra) conducted in 2006–2008.

Setting

The state of Veracruz, Mexico.

Subjects

Mexican teachers (n 20 330) provided information on body shape silhouette at baseline, changes in body shape silhouette and BMI, as well as information on sociodemographic variables and lifestyle.

Results

The median BMI was 26·8 kg/m2; 43 % of women were overweight and 24 % were obese. The carbohydrates, sweet drinks and refined foods pattern was associated with a greater risk of having a large silhouette and a large BMI (BMI ≥ 30·0 kg/m2v. BMI < 25·0 kg/m2; ORT1−3 = 1·86, 95 % CI 1·56, 2·22 and 1·47, 95 % CI 1·28, 1·69, respectively) with a significant trend when comparing the first and third tertiles of intake. The fruit and vegetable pattern was associated with a lower risk of having a large silhouette and a large BMI (ORT1−3 = 0·68, 95 % CI 0·57, 0·82 and ORT1−3 = 0·77, 95 % CI 0·67, 0·88, respectively) with a significant decreasing trend. Similar results were observed when change in silhouette (from 18 years of age to current silhouette) was considered.

Conclusions

High intakes of carbohydrates, sweet drinks and refined foods are related to larger silhouettes. Public health intervention improving access to healthy dietary guidelines, healthy food choice in the work place, promotion of physical activity and regulation of beverages with a high sugar content and of refined foods should be considered.

Does the Mediterranean dietary pattern or the Healthy Diet Index influence the risk of breast cancer in a large British cohort of women?

BACKGROUND/OBJECTIVE

To assess the risk of developing breast cancer associated with consumption of two common dietary patterns: a Mediterranean dietary pattern and a dietary pattern, which conforms to the World Health Organization Healthy Diet Index (WHO HDI).

SUBJECTS/METHODS

Dietary data from a 217-item food frequency questionnaire were used to generate two dietary patterns according to pre-defined criteria in women from the UK Women's Cohort Study. Survival analysis using Cox regression was used to estimate hazards ratios for risk of breast cancer adjusted for known confounders.

RESULTS

This analysis included 828 incident cases of breast cancer in 33,731 women with a mean follow-up of 9 years. There were no statistically significant associations between either the Mediterranean dietary pattern or the WHO HDI and risk of breast cancer. In premenopausal women, there was a nonsignificant trend suggesting that increasing compliance with the Mediterranean diet was associated with lower risk of breast cancer. Maximal adherence to the Mediterranean diet was associated with hazards ratio=0.65 (95% confidence interval: 0.42-1.02, P trend=0.09) compared with minimal adherence. In postmenopausal women, no clear trends were observed.

CONCLUSIONS

In this study, no strong association between the risk of breast cancer and the consumption of either a Mediterranean-type diet or one characterized by adherence to the WHO HDI was observed. In premenopausal, but not postmenopausal women, there was a nonsignificant inverse association with increasing adherence to the Mediterranean diet pattern.

Dietary folate, vitamin B6, vitamin B12 and methionine intake and the risk of breast cancer by oestrogen and progesterone receptor status

Few studies have evaluated the relationship between the consumption of dietary folate and one-carbon metabolism-related nutrients and breast cancer risk defined by oestrogen receptor (ER) and progesterone receptor (PR) status. The objective of the present study was to examine the associations between dietary folate, vitamin B6, vitamin B12, and methionine intake and the risk of breast cancer by ER and PR status among Chinese women in Guangdong. A hospital-based case–control study was conducted from June 2007 to August 2008, with 438 cases and 438 age (5-year interval)- and residence (rural/urban)-matched controls. Dietary intake information was assessed using a validated FFQ administered through a face-to-face interview. Unconditional logistic regression models were used to calculate multivariate-adjusted OR and 95 % CI. A significant inverse association was found between dietary folate and vitamin B6 intake and breast cancer risk. The adjusted OR of the highest v. the lowest quartile were 0·32 (95 % CI 0·21, 0·49; Ptrend < 0·001) for dietary folate and 0·46 (95 % CI 0·30, 0·69; Ptrend < 0·001) for vitamin B6. No associations were observed for vitamin B12 and methionine intake. A significant inverse association between dietary folate intake and breast cancer risk was observed in all subtypes of ER and PR status. These findings suggest that dietary folate and vitamin B6 intakes were inversely associated with breast cancer risk. The inverse association did not differ by ER and/or PR status.

Dietary patterns and the risk of colorectal adenomas: the Black Women's Health Study

BACKGROUND

Colorectal adenomas are benign lesions that may be precursors to colorectal cancer. No studies of African American women have investigated dietary patterns and the risk of developing colorectal adenomas. We examined data from the Black Women's Health Study to determine whether dietary patterns are associated with the risk of developing colorectal adenomas.

METHODS

This is a prospective cohort study of 59,000 participants followed biennially since 1995. During 155,414 person-years of follow-up from 1997 to 2007 among women who had had at least one screening colonoscopy, 620 incident cases of colorectal adenomas were identified. By using Cox regression models, we obtained incidence rate ratios (IRR) for colorectal adenoma in relation to quintiles of each of two dietary patterns, adjusting for other colorectal adenoma risk factors.

RESULTS

Two dietary patterns, Western and prudent, were utilized to assess the association between dietary intake and adenoma risk. The highest quintile of prudent diet, relative to the lowest quintile, was significantly associated with 34% lower colorectal adenoma risk overall (IRR = 0.66; 95% CI, 0.50-0.88; P(trend) < 0.01). Higher scores on the Western pattern were associated with a higher risk of developing colorectal adenoma (IRR = 1.42; 95% CI, 1.09-1.85 for the highest quintile relative to the lowest; P(trend) = 0.01).

CONCLUSION

Our findings suggest that African American women may be able to reduce their risk of developing colorectal adenomas by following a prudent dietary pattern and avoiding a more Western pattern.

IMPACT

A dietary modification could have a strong impact in colorectal adenoma prevention in African American women.

Healthy lifestyle on the risk of breast cancer

BACKGROUND

Many studies have analyzed the effect of behavioral risk factors such as common lifestyle patterns on the risk of disease. The aim of this study was to assess the effect of a healthy lifestyle index on the risk of breast cancer.

METHODS

A population-based case-control study was conducted in Mexico from 2004 to 2007. One thousand incident cases and 1,074 controls, matched to cases by 5-year age category, region, and health institution, participated in the study. A healthy lifestyle index was developed by means of principal components by using dietary pattern, physical activity, alcohol consumption, and tobacco smoking. A conditional logistic regression model was used to assess this association.

RESULTS

The healthy lifestyle index was defined as the combined effect of moderate and/or vigorous-intensity physical activity, low consumption of fat, processed foods, refined cereals, complex sugars, and the avoidance of tobacco smoking and alcohol consumption. Results showed a protective effect on both pre- (OR = 0.50, 95% CI: 0.29-0.84) and postmenopausal women (OR = O.20, 95% CI: 0.11-0.37) when highest versus lowest index quintiles were compared.

CONCLUSIONS

Healthy lifestyle was associated with a reduction in the odds of having breast cancer. Primary prevention of this disease should be promoted in an integrated manner. Effective strategies need to be identified to engage women in healthy lifestyles.

IMPACT

This study is the first to assess a healthy lifestyle index in relation to the risk of breast cancer.

3,3'-Diindolylmethane negatively regulates Cdc25A and induces a G2/M arrest by modulation of microRNA 21 in human breast cancer cells

3,3'-Diindolylmethane (DIM) is a potential chemopreventive phytochemical derived from Brassica vegetables. In this study, we assessed the effects of DIM on cell cycle regulation in both estrogen-dependent MCF-7 and estrogen receptor negative p53 mutant MDA-MB-468 human breast cancer cells. In-vitro culture studies showed that DIM dose dependently inhibited the proliferation of both cells. In addition, in-vivo xenograft model showed that DIM strongly inhibited the development of human breast tumors. Fluorescence activated cell sorter analysis showed a DIM-mediated G2/M cell cycle arrest in MCF-7 and MDA-MB-468 cells. Western blot analysis showed that DIM downregulated the expression of cyclin-dependent kinases 2 and 4 and Cdc25A, which plays an important role in G2/M phase. Furthermore, treatment of MCF-7 cells with DIM, which increased microRNA 21 expression, caused a downregulation of Cdc25A, resulting in an inhibition of breast cancer cell proliferation. Taken together, our data show that DIM is able to stop the cell cycle progression of human breast cancer cells regardless of their estrogen-dependence and p53 status, by differentially modulating cell cycle regulatory pathways. The modulation of microRNA 21 mediates the DIM cell cycle regulator effect in MCF-7 cells.

Dietary patterns and risk of breast cancer

Background:

Evidence is emerging that prudent/healthy dietary patterns might be associated with a reduced risk of breast cancer.

Methods:

Using data from the prospective Melbourne Collaborative Cohort Study, we applied principal factor analysis to 124 foods and beverages to identify dietary patterns and estimated their association with breast cancer risk overall and by tumour characteristics using Cox regression.

Results:

During an average of 14.1 years of follow-up of 20 967 women participants, 815 invasive breast cancers were diagnosed. Among the four dietary factors that we identified, only that characterised by high consumption of fruit and salad was associated with a reduced risk, with stronger associations observed for tumours not expressing oestrogen (ER) and progesterone receptors (PR). Compared with women in the lowest quintile of the factor score, the hazard ratio for women in the highest quintile was 0.92 (95% confidence interval (CI)=0.70–1.21; test for trend, P=0.5) for ER-positive or PR-positive tumours and 0.48 (95% CI=0.26–0.86; test for trend, P=0.002) for ER-negative and PR-negative tumours (test for homogeneity, P=0.01).

Conclusion:

Our study provides additional support for the hypothesis that a dietary pattern rich in fruit and salad might protect against invasive breast cancer and that the effect might be stronger for ER- and PR-negative tumours.

Fruit and vegetable intake in relation to risk of breast cancer in the Black Women's Health Study

The authors prospectively examined the relation of fruit and vegetable intake to breast cancer risk among 51,928 women aged 21-69 years at enrollment in 1995 in the Black Women's Health Study. Dietary intake was assessed by using a validated food frequency questionnaire. Cox proportional hazards models were used to estimate incidence rate ratios and 95% confidence intervals, adjusted for breast cancer risk factors. During 12 years of follow-up, there were 1,268 incident cases of breast cancer. Total fruit, total vegetable, and total fruit and vegetable intakes were not significantly associated with overall risk of breast cancer. However, total vegetable consumption was associated with a decreased risk of estrogen receptor-negative/progesterone receptor-negative breast cancer (incidence rate ratio = 0.57, 95% confidence interval: 0.38, 0.85, for ≥2 servings/day relative to <4/week; P(trend) = 0.02). In addition, there was some evidence of inverse associations with breast cancer risk overall for cruciferous vegetable intake (P(trend) = 0.06) and for carrot intake (P(trend) = 0.02). Study findings suggest that frequent consumption of vegetables is inversely associated with risk of estrogen receptor-negative/progesterone receptor-negative breast cancer, and that specific vegetables may be associated with a decreased risk of breast cancer overall.

Can rye intake decrease risk of human breast cancer?

BACKGROUND

Rye contains more fibre and bioactive compounds than other cereals used for bread production. The fibre and compounds of the fibre complex could provide protection against breast cancer (BC).

OBJECTIVE

To review the evidence and theoretical background for a role of rye and some of its components in the prevention of BC.

DESIGN

A short review based to a great extent on the work by scientists in the Nordic countries.

RESULTS

Some of the possible mechanisms by which the fibre complex could reduce BC risk are presented. The fibre through its effect on fermentation increases esterification of bile acids reducing toxicity of the free bile acids and is involved in the production of butyrate with potential anticancer effects including BC. The fibre reduces the enterohepatic circulation of the oestrogens leading to lower plasma oestrogen concentrations. The fibre complex contains bioactive compounds such as lignans and alkylresorcinols that are antioxidative and potentially anticarcinogenic. In addition, vitamins, minerals, and phytic acid in rye may provide protection against BC.

CONCLUSION

Rye products made from wholegrain rye flour are likely to contribute to reduced BC risk.

Health, alcohol and psychosocial factors in Eastern Europe study: dietary patterns and their association with socio-demographic factors in the Lithuanian urban population of Kaunas city

OBJECTIVES

The purpose of this study was to identify the main dietary patterns in the Lithuanian urban population and to determine their association with socio-demographic factors.

METHODS

Data from the survey performed in the framework of the HAPIEE (Health, Alcohol, Psychosocial factors In Eastern Europe) study were presented. A random sample of 7,087 individuals aged 45-72 years was screened in 2006-2008.

RESULTS

Factor analysis of the main dietary patterns revealed a five-factor solution, which accounted for 47.8% of the variance: "fresh vegetables and fruit"; "sweets"; "porridge and cereals"; "potatoes, meat, boiled vegetables and eggs"; "chicken and fish". "Fresh vegetables and fruits" factor and "sweets" factor were inversely associated with age both in men and women: older people consumed less frequent than average of the particular food groups. Dietary patterns of people with good self-rated health and university education were healthier than among people with lower education and poorer health.

CONCLUSION

Nutrition education efforts should focus on improving food diversity, with particular targeting of lower educated, single and older people.

Dietary patterns and risk of stomach cancer mortality: the Japan collaborative cohort study

PURPOSE

We sought to examine associations between dietary patterns and the risk of stomach cancer mortality in a cohort study in Japan.

METHODS

Factor analysis on food frequency questionnaire was conducted among 25,730 males and 37,673 females in a cohort study in Japan; we identified three dietary patterns, termed "vegetable"; "animal food"; and "dairy product". The Cox proportional hazards model was used to estimate the hazard ratio (HR) with stomach cancer mortality.

RESULTS

The "vegetable" pattern showed no association with stomach cancer mortality in either sex. The "dairy product" pattern was significantly associated with a decreased risk of stomach cancer in males, with multivariate HRs of 0.82 (95% confidence interval [CI]: 0.61-1.10), 0.74 (95% CI: 0.54-1.01), and 0.72 (95% CI: 0.52-0.99) for the second, third, and fourth quartiles, respectively. In addition, the "animal food" pattern tended to be associated with an increased risk in females, but non-significant, with HRs for respective quartiles of 1.45 (95% CI: 0.92-2.29), 1.32 (95% CI: 0.81-2.16), and 1.51 (95% CI: 0.78-2.21).

CONCLUSIONS

A diet high in dairy products may be associated with a decreased risk of stomach cancer mortality in males. We did not observe any significant association of this condition with other dietary patterns in either sex.

Dietary patterns and breast cancer risk: a systematic review and meta-analysis

BACKGROUND

Dietary patterns, which represent whole-diet and possible food and nutrient interactions, have been linked to the risk of various cancers. However, the associations of these dietary patterns with breast cancer remain unclear.

OBJECTIVE

We critically appraised the literature and conducted meta-analyses to pool the results of studies to clarify the relation between dietary patterns and breast cancer risk.

DESIGN

MEDLINE and EMBASE were searched for relevant articles that identified common dietary patterns published up to November 2009. Multivariable-adjusted odds ratios (ORs) comparing highest and lowest categories of dietary pattern scores and multivariable-adjusted ORs for a 20th-percentile increase in dietary pattern scores were combined by using random-effects meta-analyses.

RESULTS

Case-control and cohort studies were retrieved that identified prudent/healthy (n = 18), Western/unhealthy (n = 17), and drinker (n = 4) dietary patterns. There was evidence of a decrease in the risk of breast cancer in the highest compared with the lowest categories of prudent/healthy dietary patterns (OR = 0.89; 95% CI: 0.82, 0.99; P = 0.02) in all studies and in pooled cohort studies alone. An increase in the risk of breast cancer was shown for the highest compared with the lowest categories of a drinker dietary pattern (OR = 1.21; 95% CI: 1.04, 1.41; P = 0.01). There was no evidence of a difference in the risk of breast cancer between the highest and the lowest categories of Western/unhealthy dietary patterns (OR = 1.09; 95% CI: 0.98, 1.22; P = 0.12).

CONCLUSION

The results of this systematic review and meta-analysis indicate that some dietary patterns may be associated with breast cancer risk.

A vegetable-fruit-soy dietary pattern protects against breast cancer among postmenopausal Singapore Chinese women

BACKGROUND

Prospective epidemiologic studies in Asian populations consistently show that soy is protective against breast cancer.

OBJECTIVE

The objective was to prospectively evaluate whether the protective effect of soy is due to soy isoflavones alone or to their combination with other beneficial dietary factors in an Asian population.

DESIGN

Using principal components analysis, we previously identified a "meat-dim sum" pattern characterized by meat, starch, and dim sum items and a "vegetable-fruit-soy" pattern characterized by cruciferous vegetables, fruit, and tofu items in a population-based cohort of Singapore Chinese initiated between 1993 and 1998. Component scores representing intakes of each pattern were used in multivariable Cox regression models to analyze the relation between diet at baseline and breast cancer incidence.

RESULTS

As of 31 December 2005, 629 incident breast cancer cases had been diagnosed among the 34,028 women. With greater intake of the vegetable-fruit-soy dietary pattern, we observed a dose-dependent trend (P < 0.01) for decreasing breast cancer risk among postmenopausal women [hazard ratio (HR): 0.70; 95% CI: 0.51, 0.95 for the fourth compared with first quartile]. A stronger association for the vegetable-fruit-soy pattern was observed among postmenopausal women with > or =5 y of follow-up (HR: 0.57; 95% CI: 0.36, 0.88; P for trend <0.01). No trend was observed for a greater intake of the meat-dim sum dietary pattern and increased breast cancer risk.

CONCLUSION

Our findings support the hypothesis that a diet characterized by vegetables, fruit, and soy has an early-acting protective effect on breast carcinogenesis.

Multivitamins, folate, and green vegetables protect against gene promoter methylation in the aerodigestive tract of smokers

One promising approach for early detection of lung cancer is by monitoring gene promoter hypermethylation events in sputum. Epidemiologic studies suggest that dietary fruits and vegetables and the micronutrients they contain may reduce risk of lung cancer. In this study, we evaluated whether diet and multivitamin use influenced the prevalence of gene promoter methylation in cells exfoliated from the aerodigestive tract of current and former smokers. Members (N = 1,101) of the Lovelace Smokers Cohort completed the Harvard Food Frequency Questionnaire and provided a sputum sample that was assessed for promoter methylation of eight genes commonly silenced in lung cancer and associated with risk for this disease. Methylation status was categorized as low (fewer than two genes methylated) or high (two or more genes methylated). Logistic regression models were used to identify associations between methylation status and 21 dietary variables hypothesized to affect the acquisition of gene methylation. Significant protection against methylation was observed for leafy green vegetables [odds ratio (OR) = 0.83 per 12 monthly servings; 95% confidence interval (95% CI), 0.74-0.93] and folate (OR, 0.84 per 750 microg/d; 95% CI, 0.72-0.99). Protection against gene methylation was also seen with current use of multivitamins (OR, 0.57; 95% CI, 0.40-0.83). This is the first cohort-based study to identify dietary factors associated with reduced promoter methylation in cells exfoliated from the airway epithelium of smokers. Novel interventions to prevent lung cancer should be developed based on the ability of diet and dietary supplements to affect reprogramming of the epigenome.

Postmenopausal breast cancer risk and dietary patterns in the E3N-EPIC prospective cohort study

Since evidence relating diet to breast cancer risk is not sufficiently consistent to elaborate preventive proposals, the authors examined the association between dietary patterns and breast cancer risk in a large French cohort study. The analyses included 2,381 postmenopausal invasive breast cancer cases diagnosed during a median 9.7-year follow-up period (1993-2005) among 65,374 women from the E3N-EPIC cohort. Scores for dietary patterns were obtained by factor analysis, and breast cancer hazard ratios were estimated by Cox proportional hazards regression for the highest quartile of dietary pattern score versus the lowest. Two dietary patterns were identified: "alcohol/Western" (essentially meat products, French fries, appetizers, rice/pasta, potatoes, pulses, pizza/pies, canned fish, eggs, alcoholic beverages, cakes, mayonnaise, and butter/cream) and "healthy/Mediterranean" (essentially vegetables, fruits, seafood, olive oil, and sunflower oil). The first pattern was positively associated with breast cancer risk (hazard ratio = 1.20, 95% confidence interval (CI): 1.03, 1.38; P = 0.007 for linear trend), especially when tumors were estrogen receptor-positive/progesterone receptor-positive. The "healthy/Mediterranean" pattern was negatively associated with breast cancer risk (hazard ratio = 0.85, 95% CI: 0.75, 0.95; P = 0.003 for linear trend), especially when tumors were estrogen receptor-positive/progesterone receptor-negative. Adherence to a diet comprising mostly fruits, vegetables, fish, and olive/sunflower oil, along with avoidance of Western-type foods, may contribute to a substantial reduction in postmenopausal breast cancer risk.