Lifetime grain consumption and breast cancer risk

Adherence to HEI-2010 and odds of breast cancer according to the menopause status: Evidence from Middle Eastern Country

BACKGROUND

Majority of earlier studies have assessed the association between individual healthy eating index-2010 (HEI-2010) and the odds of breast cancer (BC). However, no study has been conducted on the effect of compliance with HEI-2010 and the odds of BC in the Iranian population with a large sample size. Therefore, we aimed to investigate the relationship between the HEI-2010 and the odds of BC in the Iranian population.

METHOD

This population-based case-control study included 350 newly diagnosed cases of BC and 700 healthy controls randomly selected from adult women. HEI-2010 was examined using validated questionnaires. The adherence to HEI-2010 among the participants was divided into four categories. The general characteristics of the participants in the quartiles of the HEI score for categorical variables and continuous variables were evaluated using chi-square and one-way analysis of variance, respectively. Also, using logistic regression analysis, dietary intakes were evaluated in HEI score quartiles. Also, confounding variables were adjusted in different models.

RESULT

People with the highest HEI score had 60% lower odds of BC (OR: 0.40; 95% CI: 0.27, 0.57) than those with the lowest score among post-menopause women. After controlling for age and energy intake, individuals with the highest HEI score were 78% less likely to have BC compared with those with the lowest score (OR: 0.22; 95% CI: 0.14, 0.33). Adjustments for other potential confounders including demographic factors made the association stronger (OR: 0.21; 95% CI: 0.13, 0.32). This association remained significant even after taking BMI into model (OR: 0.27; 95% CI: 0.17, 0.43).

CONCLUSION

Finally, in this study we found an association between HEI-2010 and odds of breast cancer. This association was particularly seen in postmenopausal women. No significant association was found between adherence to HEI-2010 and odds of BC among pre-menopausal.

Association of glycaemic index and glycaemic load with type 2 diabetes, cardiovascular disease, cancer, and all-cause mortality: a meta-analysis of mega cohorts of more than 100 000 participants

BACKGROUND

There is debate over whether the glycaemic index of foods relates to chronic disease. We aimed to assess the associations between glycaemic index (GI) and glycaemic load (GL) and type 2 diabetes, cardiovascular disease, diabetes-related cancers, and all-cause mortality.

METHODS

We did a meta-analysis of large cohorts (≥100 000 participants) identified from the Richard Doll Consortium. We searched the Cochrane Library, MEDLINE, PubMed, Embase, Web of Science, and Scopus for cohorts that prospectively examined associations between GI or GL and chronic disease outcomes published from database inception to Aug 4, 2023. Full-article review and extraction of summary estimates data were conducted by three independent reviewers. Primary outcomes were incident type 2 diabetes, total cardiovascular disease (including mortality), diabetes-related cancers (ie, bladder, breast, colorectal, endometrial, hepatic, pancreatic, and non-Hodgkin lymphoma), and all-cause mortality. We assessed comparisons between the lowest and highest quantiles of GI and GL, adjusting for dietary factors, and pooling their most adjusted relative risk (RR) estimates using a fixed-effects model. We also assessed associations between diets high in fibre and whole grains and the four main outcomes. The study protocol is registered with PROSPERO, CRD42023394689.

FINDINGS

From ten prospective large cohorts (six from the USA, one from Europe, two from Asia, and one international), we identified a total of 48 studies reporting associations between GI or GL and the outcomes of interest: 34 (71%) on various cancers, nine (19%) on cardiovascular disease, five (10%) on type 2 diabetes, and three (6%) on all-cause mortality. Consumption of high GI foods was associated with an increased incidence of type 2 diabetes (RR 1·27 [95% CI 1·21-1·34]; p<0·0001), total cardiovascular disease (1·15 [1·11-1·19]; p<0·0001), diabetes-related cancer (1·05 [1·02-1·08]; p=0·0010), and all-cause mortality (1·08 [1·05-1·12]; p<0·0001). Similar associations were seen between high GL and diabetes (RR 1·15 [95% CI 1·09-1·21]; p<0·0001) and total cardiovascular disease (1·15 [1·10-1·20]; p<0·0001). Associations between diets high in fibre and whole grains and the four main outcomes were similar to those for low GI diets.

INTERPRETATION

Dietary recommendations to reduce GI and GL could have effects on health outcomes that are similar to outcomes of recommendations to increase intake of fibre and whole grain.

FUNDING

Banting and Best and the Karuna Foundation.

Strategies to fortify the nutritional values of polished rice by implanting selective traits from brown rice: A nutrigenomics-based approach

Whole-grain cereals are important components of a healthy diet. It reduces the risk of many deadly diseases like cardiovascular diseases, diabetes, cancer, etc. Brown rice is an example of whole grain food, which is highly nutritious due to the presence of various bioactive compounds (flavonoids, phenolics, vitamins, phytosterols, oils, etc.) associated with the rice bran layer of brown rice. White rice is devoid of the nutritious rice bran layer and thus lacks the bioactive compounds which are the major attractants of brown rice. Therefore, to confer health benefits to the public at large, the nutrigenomic potential of white rice may be improved by integrating the phytochemicals associated with the rice bran layer of brown rice into it via biofortification processes like conventional breeding, agronomic practices, metabolic engineering, CRISPR/Cas9 technology, and RNAi techniques. Thus, this review article focuses on improving the nutritional qualities of white/polished rice through biofortification processes, utilizing new breeding technologies (NBTs).

Potential impact of time trend of whole grain intake on burden of major cancers in China

Numerous studies have revealed associations between high intake of whole grains and reduced risk of various cancers. Yet, in recent decades, the traditional Chinese diets have been challenged by reduction in whole grains and increase in refined grains. To assess the impact of this dietary transition on cancer prevention, we analyzed the time trend of whole grain intake using nationally representative sampling data of over 15 thousand individuals from the China Health and Nutrition Survey. We applied the comparative risk assessment method to estimate the population attributable fraction of cancers due to insufficient whole grain intake from 1997 to 2011 and projected the trend of whole grain intake and the associated burden of cancers to 2035. We found a significant decrease of approximately 59% of whole grain intake in the Chinese population from 1997 to 2011. Compared with 1997, insufficient intake of whole grains was responsible for 9940 more cases of breast cancer, 12,903 more cases of colorectal cancer and 434 more cases of pancreatic cancer in 2011. Our projections suggest that if every Chinese would consume 125 g whole grain per day as recommended by the latest Chinese Dietary Guidelines, 0.63% bladder cancer, 8.98% breast cancer, 15.85% colorectal cancer, 3.86% esophageal cancer, 2.52% liver cancer and 2.22% pancreatic cancer (totaling 186,659 incident cases) could theoretically be averted by 2035. Even if everyone maintained the 2011 whole grain intake level, an estimated 8.38% of cancer events could still be prevented by 2035.

Pro-Vegetarian Food Patterns and Cancer Risk among Italians from the Moli-Sani Study Cohort

Besides the Mediterranean diet, there is a paucity of studies examining plant-based diets in relation to cancer outcomes in Mediterranean populations. We analyzed 22,081 apparently cancer-free participants (mean age 55 ± 12 year) from the Moli-sani study (enrollment period 2005-2010; Italy). A general pro-vegetarian food pattern was computed by assigning positive or negative scores to plant- or animal-derived foods, respectively from a 188-item FFQ. A priori healthful or unhealthful pro-vegetarian food patterns distinguished between healthy plant foods (e.g., fruits, vegetables) and less-healthy plant foods (e.g., fruit juices, refined grains). Cancer incidence was defined as the earliest diagnosis of cancer from hospital discharge records over a median follow-up of 12.9 years. In multivariable-adjusted analyses, a general pro-vegetarian food pattern was associated with a lower rate of cancer incidence (HR = 0.85; 95%CI 0.75-0.97 for Q5 vs. Q1); no association was observed between the healthful or unhealthful pro-vegetarian food patterns and overall cancer incidence. A healthful pro-vegetarian pattern, however, was inversely associated with digestive cancer (HR = 0.76; 95%CI 0.58-0.99 for Q5 vs. Q1), while the unhealthful pro-vegetarian pattern was directly linked to respiratory cancer (HR = 1.68; 95%CI 1.06-2.68 for Q5 vs. Q1). Our findings in a Mediterranean population support the hypothesis that some, but not all pro-vegetarian diets, might prevent some cancers.

Personalized breast cancer onset prediction from lifestyle and health history information

We propose a method to predict when a woman will develop breast cancer (BCa) from her lifestyle and health history features. To address this objective, we use data from the Alberta's Tomorrow Project of 18,288 women to train Individual Survival Distribution (ISD) models to predict an individual's Breast-Cancer-Onset (BCaO) probability curve. We show that our three-step approach-(1) filling missing data with multiple imputations by chained equations, followed by (2) feature selection with the multivariate Cox method, and finally, (3) using MTLR to learn an ISD model-produced the model with the smallest L1-Hinge loss among all calibrated models with comparable C-index. We also identified 7 actionable lifestyle features that a woman can modify and illustrate how this model can predict the quantitative effects of those changes-suggesting how much each will potentially extend her BCa-free time. We anticipate this approach could be used to identify appropriate interventions for individuals with a higher likelihood of developing BCa in their lifetime.

Overview of the Composition of Whole Grains’ Phenolic Acids and Dietary Fibre and Their Effect on Chronic Non-Communicable Diseases

Chronic non-communicable diseases are the major cause of death globally. Whole grains are recommended in dietary guidelines worldwide due to increasing evidence that their consumption can improve health beyond just providing energy and nutrients. Epidemiological studies have suggested that the incorporation of whole grains, as part of a healthy diet, plays a key role in reducing one’s risk for cardiovascular diseases (CVDs), obesity, type 2 diabetes (T2D) and cancer. Phenolic acids and dietary fibre are important components found in whole grains that are largely responsible for these health advantages. Both phenolic acids and dietary fibre, which are predominantly present in the bran layer, are abundant in whole-grain cereals and pseudo-cereals. Several studies indicate that whole grain dietary fibre and phenolic acids are linked to health regulation. The main focus of this study is two-fold. First, we provide an overview of phenolic acids and dietary fibres found in whole grains (wheat, barley, oats, rice and buckwheat). Second, we review existing literature on the linkages between the consumption of whole grains and the development of the following chronic non-communicable diseases: CVDs, obesity, T2D and cancer. Altogether, scientific evidence that the intake of whole grains reduces the risk of certain chronic non-communicable disease is encouraging but not convincing. Based on previous studies, the current review encourages further research to cover the gap between the emerging science of whole grains and human health.

Healthful and Unhealthful Plant-Based Diets and Risk of Breast Cancer in U.S. Women: Results from the Nurses' Health Studies

BACKGROUND

Plant-based diets have been associated with lower risk of various diseases, including type 2 diabetes, cardiovascular disease, and other cardiometabolic risk factors. However, the association between plant-based diet quality and breast cancer remains unclear.

METHODS

We prospectively followed 76,690 women from the Nurses' Health Study (NHS, 1984-2016) and 93,295 women from the NHSII (1991-2017). Adherence to an overall plant-based diet index (PDI), a healthful PDI (hPDI), and an unhealthful PDI (uPDI) was assessed using previously developed indices. Cox proportional hazards models were used to estimate HR and 95% confidence intervals (CI) for incident invasive breast cancer.

RESULTS

Over 4,841,083 person-years of follow-up, we documented 12,482 incident invasive breast cancer cases. Women with greater adherence to PDI and hPDI were at modestly lower risk of breast cancer [(HRQ5 vs. Q1, 0.89; 95% CI, 0.84-0.95); (HRQ5 vs. Q1, 0.89; 95% CI, 0.83-0.94)]. We observed significant heterogeneity by estrogen receptor (ER) status, with the strongest inverse association between hPDI and breast cancer observed with ER-negative tumors [HRQ5 vs. Q1, 0.77; 95% CI, 0.65-0.90; P trend < 0.01]. We also found an inverse association between extreme quintiles of healthy plant foods and ER-negative breast cancer [HR, 0.74; 95% CI, 0.61-0.88; P trend < 0.01].

CONCLUSIONS

This study provides evidence that adherence to a healthful plant-based diet may reduce the risk of breast cancer, especially those that are more likely to be aggressive tumors.

IMPACT

This is the first prospective study investigating the relation between healthful and unhealthful plant-based dietary indices and risk of total and subtype-specific breast cancer.

Associations of cereal grains intake with cardiovascular disease and mortality across 21 countries in Prospective Urban and Rural Epidemiology study: prospective cohort study

OBJECTIVE

To evaluate the association between intakes of refined grains, whole grains, and white rice with cardiovascular disease, total mortality, blood lipids, and blood pressure in the Prospective Urban and Rural Epidemiology (PURE) study.

DESIGN

Prospective cohort study.

SETTING

PURE study in 21 countries.

PARTICIPANTS

148 858 participants with median follow-up of 9.5 years.

EXPOSURES

Country specific validated food frequency questionnaires were used to assess intakes of refined grains, whole grains, and white rice.

MAIN OUTCOME MEASURE

Composite of mortality or major cardiovascular events (defined as death from cardiovascular causes, non-fatal myocardial infarction, stroke, or heart failure). Hazard ratios were estimated for associations of grain intakes with mortality, major cardiovascular events, and their composite by using multivariable Cox frailty models with random intercepts to account for clustering by centre.

RESULTS

Analyses were based on 137 130 participants after exclusion of those with baseline cardiovascular disease. During follow-up, 9.2% (n=12 668) of these participants had a composite outcome event. The highest category of intake of refined grains (≥350 g/day or about 7 servings/day) was associated with higher risk of total mortality (hazard ratio 1.27, 95% confidence interval 1.11 to 1.46; P for trend=0.004), major cardiovascular disease events (1.33, 1.16 to 1.52; P for trend<0.001), and their composite (1.28, 1.15 to 1.42; P for trend<0.001) compared with the lowest category of intake (<50 g/day). Higher intakes of refined grains were associated with higher systolic blood pressure. No significant associations were found between intakes of whole grains or white rice and health outcomes.

CONCLUSION

High intake of refined grains was associated with higher risk of mortality and major cardiovascular disease events. Globally, lower consumption of refined grains should be considered.

Premenopausal breast cancer is a health challenge: nutritional habits show potential to prevent this disease

Background:

The incidence of breast cancer had increased around the world. More premenopausal women suffer from this condition with great economic and social impact. The objective of this study is to establish possible associations between lifestyle and the presence of breast cancer in premenopausal women.

Methods:

The study population was composed of 330 premenopausal patients younger than 55 years with breast disease, cared between 2013 and 2017 at the University Hospital Mayor Méderi. Two comparison groups were formed. Patients with a tumor diagnosed as malignant considering cases and control group of patients with a tumor diagnosed as benign. With factors associated significantly in the bivariate analysis (P < .10), the hierarchically organized multiple regression model controlled by the confounding variables was constructed. The logistic regression model was adjusted by the age variable, to avoid residual confounder.

Results:

The population included 330 premenopausal women with benign and malignant breast disease: 134 cases and 196 controls. From the multivariate analysis, it was identified that the whole-grain consumption was inversely associated with presence of breast cancer (odds ratio [OR] = 0.579; 95% confidence interval [CI]: 0.339, 0.991; P = .046). On the other hand, consumption of fish was associated with the presence of breast malignancy (OR = 2.560; 95% CI: 1.200, 5.460; P = .015).

Conclusions:

Considering the epigenetic and multiomics individual profiles in the development of premenopausal breast cancer and its social and economic impact can be useful in development of modern clinical strategies with crucial interventions at the primary, secondary, and tertiary prevention levels for this disease.

Diet Before and After Breast Cancer

The incidence of breast cancer has dramatically increased recently in several Asian countries. This region has experienced rapid economic growth and demographic and environmental changes. Breast cancer rates vary substantially among countries, with a lower incidence in developing countries than that in Western countries. Given the upward trend of breast cancer incidence in Asian countries and the large variation in incidence around the world, dietary changes may contribute to breast cancer development. In particular, nutrients and foods from animal sources have drawn attention as potential causes of breast cancer given that obesity and energy balance appear to be important factors associated with breast cancer risk. However, prospective cohort and intervention studies do not support the hypothesis that diet in middle life influences breast cancer development. However, recent studies have provided better insight into the roles of dietary factors in specific types of breast cancers, such as estrogen receptor-negative (ER-) breast cancer. Some studies suggest that diet in early life may play a substantial role in breast cancer development, but data and evidence remain limited.Although etiologic and epidemiologic studies have long studied modifiable risk factors for breast cancer incidence, much remains to be explored regarding the role of diet after a breast cancer diagnosis. Several epidemiologic studies have explored the factors that improve breast cancer survival rates, including diet, physical activity, and body mass index (BMI). While there is evidence of the effect of BMI on breast cancer mortality, the effects of changing dietary habits after a breast cancer diagnosis on survival or recurrence are less clear. A report of the World Cancer Research Fund stated that evidence was not sufficient to draw firm conclusions about the effect of diet and nutrition on breast cancer prognosis, but it did suggest a link between diet and breast cancer survival.The global burden of breast cancer is increasing and breast cancer is a major and emerging health problem in both developed and developing countries. For example, the five-year survival rate for Korean breast cancer patients has improved from 78.0% in 1993-1995 to 92.7% in 2012-2016. This improvement emphasizes the importance of supportive care, diet, and quality of life for breast cancer survivors. However, we have limited data of non-Western breast cancer survivors. There is a need to examine the role of diet in breast cancer survival in both Western and non-Western regions.

Whole Grains, Refined Grains, and Cancer Risk: A Systematic Review of Meta-Analyses of Observational Studies

PubMed, Web of Science, and the Cochrane Database of Systematic Reviews were searched for meta-analyses that provided risk estimates (±95% confidence intervals) for associations between intakes of whole and refined grains and risk of total and site-specific cancer. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were followed. Only meta-analyses that included whole grains and refined grains as separate food groups, and not as part of dietary patterns, were included. A total of 17 publications were identified that met inclusion criteria. Within these, results from a total of 54 distinct meta-analyses were reported for whole grains and 5 meta-analyses for refined grains. For total cancer mortality, 7 meta-analyses of cohort studies indicated that whole grain intake was associated with 6% to 12% lower risk in comparison of highest vs. lowest intake groups, and 3% to 20% lower risk for doses ranging from 15 to 90 g/day. For site-specific cancers, meta-analyses indicated that whole grain intake was consistently associated with lower risks of colorectal, colon, gastric, pancreatic, and esophageal cancers. Limited data were available for refined grains, with only 4 publications providing risk estimates, and only 1 of the meta-analyses included more than 3 studies. High intake of refined grains was associated with increased risk of colon and gastric cancer. By contrast, in the only dose-response meta-analysis, each 90 g/day consumption of refined grains was associated with a 6% lower risk of total cancer. In addition to the limited number of published meta-analyses on refined grains, results were also weakened due to the fact that refined grains were frequently defined to include both staple grain foods and indulgent grain foods, and the majority of studies included in the meta-analyses provided no specific definition of refined grains. Overall, meta-analyses of cohort and case-control studies consistently demonstrate that whole grain intake is associated with lower risk of total and site-specific cancer, and support current dietary recommendations to increase whole grain consumption. By contrast, the relationship between refined grain intake and cancer risk is inconclusive.

Intake of Various Food Groups and Risk of Breast Cancer: A Systematic Review and Dose-Response Meta-Analysis of Prospective Studies

Despite increasing evidence for the association of food-based dietary patterns with breast cancer risk, knowledge about the shape of the relationship and the quality of meta-evidence are insufficient. We aimed to summarize the associations between food groups and risks of breast cancer. We performed a systematic literature search of the PubMed and Embase databases up to March 2020. We included cohort, case-cohort, nested case-control studies, and follow-up studies of randomized controlled trials that investigated the relationship between breast cancer risk and at least 1 of the following food groups: red meat, processed meat, fish, poultry, egg, vegetables, fruit, dairy product (overall, milk, yogurt, and cheese), grains/cereals, nuts, legumes, soy, and sugar-sweetened beverages. Summary risk ratios (RRs) and 95% CIs were estimated using a random-effects model for linear and nonlinear relationships. Inverse linear associations were observed for vegetables (RR per 100 g/d, 0.97; 95% CI, 0.95-0.99), fruit (RR per 100 g/d, 0.97; 95% CI, 0.95-0.99), cheese (RR per 30 g/d, 0.95; 95% CI, 0.91-1.00), and soy (RR per 30 g/d, 0.96; 95% CI, 0.94-0.99), while positive associations were observed for red (RR per 100 g/d, 1.10; 95% CI, 1.03-1.18) and processed meat (RR per 50 g/d, 1.18; 95% CI, 1.04-1.33). None of the other food groups were significantly associated with breast cancer risk. A nonlinear association was observed only for milk, such that the intake of >450 g/d increased the risk, while no association was observed for lower intake amounts. High intakes of vegetables, fruit, cheese, and soy products and low intakes of red and processed meat were associated with lower risks of breast cancer. However, causality cannot be inferred from these statistical correlations.

Grain and dietary fiber intake and bladder cancer risk: a pooled analysis of prospective cohort studies

BACKGROUND

Higher intakes of whole grains and dietary fiber have been associated with lower risk of insulin resistance, hyperinsulinemia, and inflammation, which are known predisposing factors for cancer.

OBJECTIVES

Because the evidence of association with bladder cancer (BC) is limited, we aimed to assess associations with BC risk for intakes of whole grains, refined grains, and dietary fiber.

METHODS

We pooled individual data from 574,726 participants in 13 cohort studies, 3214 of whom developed incident BC. HRs, with corresponding 95% CIs, were estimated using Cox regression models stratified on cohort. Dose-response relations were examined using fractional polynomial regression models.

RESULTS

We found that higher intake of total whole grain was associated with lower risk of BC (comparing highest with lowest intake tertile: HR: 0.87; 95% CI: 0.77, 0.98; HR per 1-SD increment: 0.95; 95% CI: 0.91, 0.99; P for trend: 0.023). No association was observed for intake of total refined grain. Intake of total dietary fiber was also inversely associated with BC risk (comparing highest with lowest intake tertile: HR: 0.86; 95% CI: 0.76, 0.98; HR per 1-SD increment: 0.91; 95% CI: 0.82, 0.98; P for trend: 0.021). In addition, dose-response analyses gave estimated HRs of 0.97 (95% CI: 0.95, 0.99) for intake of total whole grain and 0.96 (95% CI: 0.94, 0.98) for intake of total dietary fiber per 5-g daily increment. When considered jointly, highest intake of whole grains with the highest intake of dietary fiber showed 28% reduced risk (95% CI: 0.54, 0.93; P for trend: 0.031) of BC compared with the lowest intakes, suggesting potential synergism.

CONCLUSIONS

Higher intakes of total whole grain and total dietary fiber are associated with reduced risk of BC individually and jointly. Further studies are needed to clarify the underlying mechanisms for these findings.

Mediterranean diet and breast cancer risk: a narrative review

Breast cancer is the second most frequent type of cancer worldwide and the most commonly occurring malignancy in women, and its incidence is increasing in most developed and developing countries. There is growing evidence that lifestyle factors, in particular diet may be associated with higher breast cancer risk. Some evidence exists regarding the benefit of Mediterranean diet on reduced risk of breast cancer in premenopausal and postmenopausal women. The protective effect of the Mediterranean diet against the risk of breast cancer, is primarily due to principal foods of this nutritional pattern. The principal components of the Mediterranean diet, such as fruits and vegetables, olive oil, fish and red wine have important antioxidants properties due to their high content of substances like polyphenols, flavonoids, carotenoids and fibers, along with a favorable fatty acid profile, that in turn could reduce the risk of breast cancer. Considering the severity of breast cancer and the increasing incidence in the world, there is an increasing interest in promoting prevention strategies in order to reduce the incidence. The aim of this paper is to provide a general overview of the current evidence on the relationship between breast cancer and Mediterranean diet, in premenopausal and postmenopausal women, and to emphasize the potential role of Mediterranean Diet as an effective tool in primary prevention. The possible molecular mechanisms underlying this association will be also pointed out.

Plant Foods, Antioxidant Biomarkers, and the Risk of Cardiovascular Disease, Cancer, and Mortality: A Review of the Evidence

Although a high intake of plant foods such as fruits, vegetables, whole grains, nuts, and legumes has been recommended for chronic disease prevention, it has been unclear what is the optimal amount of intake of these foods and whether specific subtypes are particularly beneficial. The evidence from several recently published meta-analyses on plant foods and antioxidants and various health outcomes is reviewed as well as more recently published studies. In meta-analyses of prospective studies, inverse associations were observed between intake of fruits, vegetables, whole grains, and nuts and the risk of coronary artery disease, stroke, cardiovascular disease overall, total cancer, and all-cause mortality. The strongest reductions in risk were observed at an intake of 800 g/d for fruits and vegetables, 225 g/d for whole grains, and 15-20 g/d for nuts, respectively. Whole-grain and nut consumption was also inversely associated with mortality from respiratory disease, infections, and diabetes. Stronger and more linear inverse associations were observed between blood concentrations of antioxidants (vitamin C, carotenoids, vitamin E) and cardiovascular disease, cancer, and all-cause mortality than for dietary intake. Most studies that have since been published have been consistent with these results; however, further studies are needed on subtypes of plant foods and less common causes of death. These results strongly support dietary recommendations to increase intake of plant foods, and suggest optimal intakes for chronic disease prevention may be ∼800 g/d for intakes of fruits and vegetables, 225 g/d for whole grains, and 15-20 g/d for nuts. Diets high in plant foods could potentially prevent several million premature deaths each year if adopted globally.

Breast cancer prevention in premenopausal women: role of the Mediterranean diet and its components

Breast cancer (BC) is a growing public health concern in most developed and developing countries. Since an increasing number of patients with BC are diagnosed before the menopause and premenopausal women show a more aggressive phenotype, there is consistent interest in promoting prevention strategies in order to reduce the incidence of BC in the premenopause. The Mediterranean diet (MD) has been reported to have beneficial effect in terms of cancer prevention. This healthy dietary pattern consists primarily of foods having important antioxidant properties along with a favourable fatty acid profile, all associated with a reduced risk of cancer. Due to the large variability in study subject characteristics, the protective role of the MD on BC still remains controversial and studies that have investigated the association between adherence to the MD and risk of BC in premenopausal women are fewer than those in postmenopausal women. In addition, the possibility that the beneficial effects of the MD are due to a single component or might more probably derive from the synergic effects of all components of the MD remains a scantly explored field. Considering the increased risk of recurrence and mortality rate of BC in premenopausal women as compared with postmenopausal women, the aim of the present report is to provide a general overview of the current evidence on the relationship between BC and the MD specifically in premenopausal women, and to emphasise the potential role of the MD as an effective measure to reduce the risk of developing BC in premenopausal women.

Whole Grain Consumption for the Prevention and Treatment of Breast Cancer

Breast cancer is one of the most common and malignant cancers among females worldwide. Several epidemiological studies have indicated the inverse correlation between the intake of whole grains and the incidence of breast cancer. Whole grains are the most fundamental and important food source of bioactive phytochemicals, which have well-defined roles in the management of each stage of breast carcinogenesis. To better understand the value of whole grains in future prevention and treatment of breast cancer, the effects and possible mechanisms of six different whole grain cereals, which are the most commonly consumed throughout the world, are introduced in the current review. Moreover, the bioactive compounds extracted from whole grains are adequately formulated and the underlying mechanism of action is illustrated. In addition, the present limitations and future perspective of whole grain consumption for breast cancer are also concluded. The objective of this review is to promote the development of nutraceutical and functional food from whole grains and its application for reducing the risk of breast cancer.

Dietary intake from birth through adolescence in relation to risk of benign breast disease in young women

PURPOSE

Nutritional factors during different periods in life impact breast cancer risk. Because benign breast disease (BBD) is a well-established risk factor for breast cancer, we investigated childhood nutrition from birth through age 14 year and subsequent BBD.

METHODS

A prospective cohort study of 9031 females, 9-15 year at baseline, completed questionnaires (including heights, weights) annually from 1996 to 2001, in 2003, 2005, 2007, 2010, 2013 and 2014. In 1996, mothers reported infant feeding practices during their daughters first year of life. Beginning in 1996, participants completed annual food frequency questionnaires. In 2005, participants (18 year +) began reporting whether they had ever been diagnosed with biopsy-confirmed BBD (N = 173 cases). Multivariable logistic regression models estimated associations between childhood nutrition and BBD, adjusted for maternal breast disease and childhood body size factors.

RESULTS

Although no infant nutrition factors were associated with biopsy-confirmed BBD, certain adolescent dietary factors were. A multivariable model simultaneously included the most important diet and body size factors from different age periods: higher BBD risk was associated with greater age 10 year consumption of animal (non-dairy, energy-adjusted) fat (OR 2.27, p < .02, top vs. bottom quartiles) and with lower 14 year consumption of nuts/peanut butter (OR 0.60, p = .033, top vs. bottom quartiles).

CONCLUSION

Greater intake of animal (non-dairy) fat at 10 year and lower intake of nuts/peanut butter at 14 year were independently associated with higher BBD risk. These dietary factors appeared to operate on BBD risk independent of childhood growth (gestational weight gain, childhood BMI and height, adolescent height growth velocity), young adult height and BMI, and family history.

Perspective: Refined Grains and Health: Genuine Risk, or Guilt by Association?

Refined grain intake is widely assumed to be associated with adverse health outcomes, including increased risk for cardiovascular disease (CVD), type 2 diabetes (T2D), and obesity. The 2015 Dietary Guidelines Advisory Committee recommended that to improve dietary quality, the US population should replace most refined grains with whole grains. This recommendation was based largely on results from studies that examined dietary patterns, not separate food groups. A Western dietary pattern typically includes red and processed meat, sugar-sweetened foods and beverages, French fries, and high-fat dairy products, as well as refined grains, and has been linked to increased risk of many chronic diseases. However, when evaluated as a distinct food category, 11 meta-analyses of prospective cohort studies, which included a total of 32 publications with data from 24 distinct cohorts, demonstrated that refined grain intake was not associated with all-cause mortality, T2D, CVD, coronary heart disease (CHD), stroke, hypertension, or cancer. By contrast, consumption of red and processed meat was consistently associated with increased risk of these same health outcomes. Refined grain consumption up to 6-7 servings/d (1 serving = 30 g) was not associated with higher risk of CHD, T2D, hypertension, or all-cause mortality. Moreover, total grain intake was not associated with risk of CVD, CHD, stroke, or cancer, but was associated with lower risk of all-cause mortality. Consequently, the recommendation to reduce refined grain intake based on results from studies linking a Western dietary pattern to numerous adverse health outcomes is contrary to a substantial body of published scientific evidence. Future research needs to better define refined grain intake to distinguish between staple grain foods and indulgent grain foods, and to better design randomized controlled trials to resolve discrepancies between results from observational studies and such trials with regard to determining the benefits of whole grains compared with refined grains.

Dietary index scores and invasive breast cancer risk among women with a family history of breast cancer

BACKGROUND

Many epidemiologic studies have analyzed the relations of individual foods and nutrients and breast cancer risk with inconsistent results. Few studies have examined recommendation-based dietary indices and breast cancer risk.

OBJECTIVE

The aim of this study was to determine associations between recommendation-based dietary index scores and incident invasive breast cancer.

METHODS

The Sister Study is a prospective cohort of 50,884 US women (baseline: 2003-2009) who had a sister with breast cancer but no prior breast cancer themselves. We created scores for the Dietary Approaches to Stop Hypertension (DASH) diet, Alternative Mediterranean Diet (AMED), and Alternative Healthy Eating Index-2010 (AHEI-2010) from dietary intakes estimated by a baseline-validated Block food-frequency questionnaire (FFQ). We used Cox regression to estimate multivariable-adjusted HRs and 95% CIs for total invasive breast cancer risk and by estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2) status.

RESULTS

We documented 1,700 invasive breast cancer cases through 2015 (mean follow-up, 7.6 y). Individuals in the highest quartile of DASH scores had a lower risk of invasive breast cancer compared with those in the lowest quartile (HR: 0.78; 95% CI: 0.67, 0.90; P-trend = 0.001), with stronger associations for ER- (HR: 0.61; 95% CI: 0.40, 0.94; P-trend = 0.006) as well as ER-/PR- and ER-/PR-/HER2- subtypes. AHEI-2010 (HR for highest compared with lowest quartile: 0.90; 95% CI: 0.78, 1.03; P-trend = 0.15) and AMED (HR for highest compared with lowest quartile: 0.90; 95% CI: 0.77, 1.06; P-trend = 0.07) were weakly and nonsignificantly associated with breast cancer risk, but after excluding alcohol, AHEI-2010 was inversely associated with risk of ER-/PR- (HR: 0.64; 95% CI: 0.42, 0.98; P-trend = 0.04) and ER-/PR-/HER2- subtypes. We did not observe any significant interactions by menopausal status or other participant characteristics.

CONCLUSIONS

DASH scores were inversely associated with breast cancer risk; DASH and AHEI-2010 scores excluding alcohol were particularly inversely associated with risk of ER-/PR- and ER-/PR-/HER2- breast cancers. This trial was registered at clinicaltrials.gov as NCT00047970.

Long-Term Whole Grain Wheat and Rye Intake Reflected by Adipose Tissue Alkylresorcinols and Breast Cancer: A Case-Cohort Study

Whole grain rye (WGR) and whole grain wheat (WGW) have been suggested to protect against the development of breast cancer. In this study, we estimated long-term intake of WGR and WGW, using both a food frequency questionnaire (FFQ) and alkylresorcinol concentrations in adipose tissue biopsies, in relation to the risk of developing invasive breast cancer in a case-cohort study (n = 414 in the case group, n = 933 in the subcohort group) on the Danish “Diet, Cancer and Health” cohort. The median follow-up time of the subcohort was 5.3 years. Total WGR and WGW intake estimated with FFQ or reflected by total alkylresorcinol concentration in adipose tissue was not significantly associated with risk of breast cancer. However, after adjustment for total WGR and WGW intake, women in the highest quartile of relative WGR intake, reflected by the alkylresorcinol C17:0/C21:0 ratio, had a higher risk of overall breast cancer and estrogen-receptor-positive (ER+) breast cancer than women in the lowest quartile of relative WGR intake, while the risk of estrogen-receptor-negative (ER-) breast cancer incidence was unaffected. Similar results were obtained with the FFQ data. Based on these data, further investigation of the role of specific grain types in reducing or increasing breast cancer risk, and their overall impact on health, is warranted.

Association between whole grain intake and breast cancer risk: a systematic review and meta-analysis of observational studies

Background

Epidemiological studies have found that high whole grain intake may be associated with a reduced risk of breast cancer. However, the evidence has not been consistent. We conducted a meta-analysis to quantitatively assess the association between whole grain intake and breast cancer risk.

Methods

Relevant observational studies were identified by searching PubMed, Embase, Cochrane library databases, and Google Scholar through April 2017. Summary relative risk (RR) estimates were calculated using random-effects meta-analysis.

Results

A total of 11 studies, including 4 cohort and 7 case-control studies and involving 131,151 participants and 11,589 breast cancer cases, were included in the current meta-analysis. The pooled RR of breast cancer for those with high versus low whole grain intake was 0.84 (95% confidence interval [CI]: 0.74 to 0.96, p = 0.009; I² = 63.8%, p_{for heterogeneity} = 0.002). Subgroup analysis by study design found a significant inverse association in the case-control studies (RR: 0.69; 95% CI: 0.56 to 0.87, p = 0.001; I² = 58.2%, p _{for heterogeneity} = 0.026), but not in the cohort studies (RR, 0.96; 95% CI: 0.82 to 1.14, p = 0.69; I² = 66.7%, p for heterogeneity = 0.029). In addition, stratified analysis suggested that sample size could be a potential source of heterogeneity.

Conclusions

Results of the current meta-analysis suggest that high intake of whole grains might be inversely associated with a reduced risk of breast cancer, and the inverse association was only observed in case-control but not cohort studies. More large-scale cohort studies are needed to confirm the inverse association observed.

Electronic supplementary material

The online version of this article (10.1186/s12937-018-0394-2) contains supplementary material, which is available to authorized users.

Associations of Whole and Refined Grain Intakes with Adiposity-Related Cancer Risk in the Framingham Offspring Cohort (1991-2013)

Case-control studies suggest that higher whole grain and lower refined grain intakes are associated with reduced cancer risk, but longitudinal evidence is limited. The objective of this prospective cohort study is to evaluate associations between whole and refined grains and their food sources in relation to adiposity-related cancer risk. Participants were adults from the Framingham Offspring cohort (N = 3,184; ≥18 yr). Diet, measured using a food frequency questionnaire, medical and lifestyle data were collected at exam 5 (1991-95). Between 1991 and 2013, 565 adiposity-related cancers were ascertained using pathology reports. Cox proportional hazards models were used to estimate adjusted hazard ratios and 95% confidence intervals for associations of whole and refined grains with risk of adiposity-related cancers combined and with risk of breast and prostate cancers in exploratory site-specific analyses. Null associations between whole and refined grains and combined incidence of adiposity-related cancers were observed in multivariable-adjusted models (HR: 0.94; 95% CI: 0.71-1.23 and HR: 0.98; 95% CI: 0.70-1.38, respectively). In exploratory analyses, higher intakes of whole grains (oz eq/day) and whole grain food sources (servings/day) were associated with 39% and 47% lower breast cancer risk (HR: 0.61; 95% CI: 0.38-0.98 and HR: 0.53; 95% CI: 0.33-0.86, respectively). In conclusion, whole and refined grains were not associated with adiposity-related cancer risk. Whole grains may protect against breast cancer, but findings require confirmation within a larger sample and in other ethnic groups.

Dietary habits in adolescence and midlife and risk of breast cancer in older women

Recent studies indicate that lifestyle factors in early life affect breast cancer risk. We therefore explored the association of high consumption of meat, milk, and whole grain products in adolescence and midlife, on breast cancer risk. We used data from the population based AGES-Reykjavik cohort (2002–2006), where 3,326 women with a mean age of 77 years (SD 6.0) participated. For food items and principal component derived dietary patterns we used Cox proportional models to calculate multivariate hazard ratios (HR) with 95% confidence intervals (95% CI). During a mean follow-up of 8.8 years, 97 women were diagnosed with breast cancer. For both adolescence and midlife, daily consumption of rye bread was positively associated with breast cancer (HR 1.7, 95% CI 1.1–2.6 and HR 1.8, 95% CI 1.1–2.9, respectively). In contrast, persistent high consumption of oatmeal was negatively associated with breast cancer (0.4, 95% CI 0.2–0.9). No association was found for other food items or dietary patterns that included rye bread. High rye bread consumption in adolescence and midlife may increase risk of late-life breast cancer whilst persistent consumption of oatmeal may reduce the risk.

Intake of bean fiber, beans, and grains and reduced risk of hormone receptor-negative breast cancer: the San Francisco Bay Area Breast Cancer Study

High dietary fiber intake has been associated with reduced breast cancer risk, but few studies considered tumor subtypes defined by estrogen receptor (ER) and progesterone receptor (PR) status or included racial/ethnic minority populations who vary in their fiber intake. We analyzed food frequency data from a population-based case-control study, including 2135 breast cancer cases (1070 Hispanics, 493 African Americans, and 572 non-Hispanic Whites (NHWs)) and 2571 controls (1391 Hispanics, 557 African Americans, and 623 NHWs). Odds ratios (OR) and 95% confidence intervals (CI) for breast cancer associated with fiber intake were calculated using unconditional logistic regression. Breast cancer risk associated with high intake (high vs. low quartile) of bean fiber (p-trend = 0.01), total beans (p-trend = 0.03), or total grains (p-trend = 0.05) was reduced by 20%. Inverse associations were strongest for ER-PR- breast cancer, with risk reductions associated with high intake ranging from 28 to 36%. For bean fiber, risk was reduced among foreign-born Hispanics only, who had the highest fiber intake, whereas for grain intake, inverse associations were found among NHWs only. There was no evidence of association with fiber intake from vegetables and fruits or total intake of vegetables and fruits. A high dietary intake of bean fiber and fiber-rich foods such as beans and grains may lower the risk of ER-PR- breast cancer, an aggressive breast cancer subtype for which few risk factors have been identified.

Dietary Factors and Female Breast Cancer Risk: A Prospective Cohort Study

Breast cancer is the leading cause of cancer in females and has become a major global health priority. This prospective cohort study investigated the association of dietary factors, including food items and dietary habits, with the risk of breast cancer in Korean women. Study participants were women aged 30 years or older, recruited from the National Cancer Center in South Korea between August 2002 and May 2007. They were followed until December 2014 using the Korea Central Cancer Registry to identify breast cancer cases. Among 5046 non-pre-diagnosed cancer participants, 72 breast cancer cases were prospectively identified. Participants with breast cancer had a significantly higher educational level (college or higher: 58.3% vs. 39.5%, p = 0.01), were more likely to have ever smoked (22.2% vs. 7.8%, p < 0.001), and were more likely to have a history of benign breast tumors (10% vs. 4%, p = 0.02) than non-cases. Consumption of grilled meat conferred a significantly higher risk of breast cancer in all women (hazard ratio (HR) 1.77, 95% confidence interval (CI) 1.09–2.85) and in postmenopausal women (HR 3.06, 95% CI 1.31–7.15). High-cholesterol food intake was associated with a higher risk in all women (HR 1.69, 95% CI 1.01–2.82). Irregular meal intake was associated with an elevated risk in all women (HR 2.19, 95% CI 1.20–3.98, p for trend = 0.01) and in premenopausal women (HR 2.35, 95% CI 1.13–4.91, p for trend = 0.03). Our findings suggest that grilled meat and high-cholesterol food intake and irregular eating habits may be associated with a higher risk of breast cancer. Further studies with longer follow-up periods that include information on portion size, hormone receptor status, carcinogen levels in grilled meat, and a classification of foods by source are required.

Associations of dietary carbohydrates, glycaemic index and glycaemic load with risk of bladder cancer: a case-control study

Carbohydrate foods with high glycaemic index (GI) and load (GL) may negatively influence cancer risk. We studied the association of dietary carbohydrates, GI, GL, intake of bread and pasta with risk of bladder cancer using data from an Italian case-control study. The study included 578 men and women with histologically confirmed bladder cancer and 608 controls admitted to the same hospitals as cases for acute, non-neoplastic conditions. OR were estimated by logistic regression models after allowance for relevant confounding factors. OR of bladder cancer for the highest v. the lowest quantile of intake were 1·52 (95 % CI 0·85, 2·69) for available carbohydrates, 1·18 (95 % CI 0·83, 1·67) for GI, 1·96 (95 % CI 1·16, 3·31, P trend<0·01) for GL, 1·58 (95 % CI 1·09, 2·29, P trend=0·03) for pasta and 1·92 (95 % CI 1·28, 2·86, P trend<0·01) for bread. OR for regular consumption of legumes and whole-grain products were 0·78 (95 % CI 0·60, 1·00) and 0·82 (95 % CI 0·63, 1·08), respectively. No heterogeneity in risks emerged across strata of sex. This case-control study showed that bladder cancer risk was directly associated with high dietary GL and with consumption of high quantity of refined carbohydrate foods, particularly bread. These associations were apparently stronger in subjects with low vegetable consumption.

Association of Pasta Consumption with Diet Quality and Nutrients of Public Health Concern in Adults: National Health and Nutrition Examination Survey 2009-2012

Background: Pasta is a commonly consumed food in the United States; however, little is known about pasta consumption and nutrient intake and diet quality. Objective: This study examined the association between pasta consumption and diet quality. Methods: This was a cross-sectional data analysis of 10,697 US adults from the NHANES 2009-2012, a nationally representative survey. The main outcome measures were diet quality as assessed by the Healthy Eating Index-2010 (HEI-2010), nutrient intakes, and dietary patterns. Cluster analysis was used among pasta consumers to characterize dietary patterns. Regression analyses determined differences between groups. Results: Overall mean diet quality was similar between pasta consumers and nonconsumers. However, consumers of "pasta, noodles" had 5.6% higher HEI-2010 scores; HEI-2010 scores were 7.9% lower in those who ate "macaroni and cheese." Consumers of pasta, "pasta, noodles," and "pasta mixed dishes, excluding macaroni and cheese" ("pasta mixed dishes") had higher dietary fiber intakes by 11.0-13.6% (range: 1.89-2.35 g/d). Consumption of "pasta mixed dishes" was associated with a 5% increase in both potassium and sodium intakes (∼150 and 190 mg/d, respectively). Cluster analyses identified pasta-eating patterns that are associated with both increased and decreased diet quality compared with nonconsumers. Conclusions: Different dietary patterns exist with regard to pasta consumption. These pasta patterns contribute in different ways to diet quality and intakes of fiber, sodium, and potassium. Therefore, it is critical to separate types of pasta and pasta dishes before relating to dietary intakes.