Meta-analysis: dietary fat intake, serum estrogen levels, and the risk of breast cancer

Dietary soluble, insoluble, and total fiber intake and their dietary sources in association with breast cancer

BACKGROUND

A few studies have examined the association between different types of dietary fiber as well as their sources and the risk of breast cancer (BC) and the present study aimed to investigate these associations in a case-control study among Iranian women.

METHODS

A total of 464 women with pathologically confirmed breast cancer within the past year and 498 age-matched healthy controls were included. Dietary intakes were assessed using a 168-item food frequency questionnaire. The association between dietary soluble, insoluble, total dietary fiber, as well as, fiber from fruits, vegetables, legumes, cereals, and nuts intake with odds of breast cancer was assessed using multivariate logistic regression analysis.

RESULTS

Mean total dietary fiber intake of patients with and without cancer were 33.1 ± 15.3 g per day (g/d) and 34.2 ± 16.5 (g/d), respectively. Dietary total fiber (OR = 0.65; 95%CI: 0.47-0.90, Ptrend = 0.01), insoluble fiber (OR = 0.68; 95%CI: 0.49-0.93, Ptrend = 0.01), fruits' fiber (OR = 0.68; 95%CI: 0.49-0.94, Ptrend = 0.02), and vegetables' fiber (OR = 0.66; 95%CI: 0.48-0.91, Ptrend = 0.01) were significantly associated with reduced likelihood of developing breast cancer in all participants. Furthermore, dietary total and insoluble fiber, as well as, fiber from fruits were significantly associated with lower odds of breast cancer in premenopausal women (P < 0.05). In contrast, cereals' fiber significantly increased the risk of breast cancer by 84% in premenopausal women (OR = 1.84; 95%CI: 1.18-2.86, Ptrend = 0.009). In postmenopausal women, cereals' fiber had a significant inverse association with odds of breast cancer (OR = 0.56; 95%CI: 0.31-1.03, Ptrend = 0.04). Also, fiber from vegetables was significantly associated with a lower risk of breast cancer in postmenopausal women (OR = 0.53; 95%CI: 0.30-0.94, Ptrend = 0.03).

CONCLUSION

Dietary fiber intake and more specifically insoluble, fruits', and vegetables' fiber intake might be associated with a reduced breast cancer risk, particularly in premenopausal women. Future prospective investigations are needed to confirm these findings.

The impact of vegetarian diet on sperm quality, sex hormone levels and fertility: a systematic review and meta-analysis

BACKGROUND

An increasing number of people have adhered to a vegetarian diet for several years. Nowadays, the favourable effect of this dietary pattern on metabolic diseases is well established, but its impact on fertility and reproductive health as a serious health concern is not clear yet. Therefore, we aim to summarise existing evidence regarding the possible association between a vegetarian diet and fertility as measured by key indicators such as sperm quality and sex hormone levels.

METHODS

We systematically searched online databases, including PubMed, ISI, Scopus and Google Scholar, up to 1 December 2022 using relevant keywords. We included observational studies that compared semen quality, sex hormone levels and infertility in people who adhered to a vegetarian diet versus an omnivore diet. Heterogeneity between studies was assessed using I2 and Q tests. Standardised mean differences (SMD) using a random/fixed model were calculated to assess outcomes between vegetarians and omnivores in included articles.

RESULTS

Finally, out of 972 documents that were retrieved, 20 articles met our inclusion criteria, and 16 were eligible for quantitative synthesis. Results of meta-analyses showed that there were no significant differences between vegetarians and omnivores in terms of semen quality parameters, including total sperm count, total and progressive sperm motility, sperm morphology and sperm concentration. Seven studies on female sex hormone profiles were eligible for meta-analysis. The only significant difference was the lower level of plasma oestrone in vegetarians (pooled SMD: -0.56; 95% confidence interval [CI]: -1.08, -0.05; p-value = 0.03) compared to omnivores. Furthermore, our meta-analysis revealed significantly higher sex-hormone-binding globulin levels in vegetarian men than in omnivores (pooled SMD: 0.52; 95% CI: 0.18, 0.86; p-value = 0.002).

CONCLUSION

Despite the numerous health benefits of a vegetarian diet, our review suggested that there were no conclusive positive or negative associations between vegetarian diet and semen quality, sex hormone levels and infertility. Further studies are recommended to better understand vegetarian dietary pattern effect on infertility and reproductive health.

Sleep Quality in Women with Premenstrual Syndrome Is Associated with Metabolic Syndrome-Related Variables

In this study, we examined whether metabolic syndrome (MetS)-related variables are simultaneously affected by sleep quality, premenstrual syndrome (PMS) and dietary consumption. In this cross-sectional study, data for 307 premenopausal women were available. The results showed that women experiencing PMS had significantly lower sleep quality and were more depressed and anxious (p < 0.001 for all). After the subjects were divided into groups according to PMS, the effect of sleep quality on MetS-related variables or MetS components significantly differed; only among women who experienced PMS were poor sleepers significantly higher in waist circumference (p = 0.018) and diastolic blood pressure (p = 0.012) than good sleepers. Among the MetS components, abdominal obesity in women with poor sleep quality was approximately three (16.9% vs. 3.0%, p= 0.020) times more common than in those with good sleep quality. However, these findings were not observed among those who did not experience PMS. Poor sleepers among women experiencing PMS consumed 2.8 times more alcoholic drinks than good sleepers (p = 0.006). The MetS-related variables in Korean women experiencing PMS are associated with sleep quality, and these associations may be modified by dietary habits.

Effects of caste, birth season, and family income on digit ratios

OBJECTIVES

The contributions of latitude and ethnicity in the determination of cross-society differences in digit ratios are unclear. In India, different castes (endogamous groups) have been living in the same areas (villages or towns) for the last 1500 years and, therefore, these groups may have different gene pools without a latitude-related difference component. Thus, in the present study, we studied the effect of caste on digit ratios. We also studied the effects of sex, birth season, and family income on digit ratios.

METHODS

We selected a sample of 301 college students (age: M = 19.9 years, SD = 2.63) in Muzaffarnagar city of western Uttar Pradesh, India, and asked participants for information regarding their birth month, religion, caste, and monthly family income. We measured participants' dorsal and palmar digit lengths (of all fingers, except the thumb, in both hands) using vernier calipers of 0.01 mm accuracy.

RESULTS

Other backward castes (intermediate castes) had longer digit lengths than general castes (upper castes), scheduled castes (lower castes), and Muslims. However, there was no difference in digit ratios of caste groups (scheduled castes vs. other backward castes vs. general castes vs. Muslims) or specific castes (Chamar-Jatav vs. Jat vs. Pandit-Tyagi). Winter-born women had lower left dorsal 2D:4D and 3D:4D ratios than summer-born women. Family income was related to higher dorsal 2D:4D and 3D:4D ratios among women. Moreover, in dorsal digit ratios, sex difference (men < women) occurred in digit ratios constituting digit 5, whereas, in palmar digit ratios, sex difference occurred in digit ratios constituting digit 2.

CONCLUSIONS

The present study suggests that endogamy-led genetic difference in ethnic/caste groups is not a determinant, whereas birth season (i.e., the exposure to sunlight) and family income might be determinants of digit ratios. In addition, compared to palmar digit ratios, dorsal digit ratios are better markers of sexual dimorphism.

Food groups and nutrients consumption and risk of endometriosis: a systematic review and meta-analysis of observational studies

Dietary factors may play a role in the etiology of endometriosis and dietary intake of some food groups and nutrients could be associated with endometriosis risk. This systematic review and meta-analysis of observational studies was conducted to summarize the findings on the association between dietary intakes of selected food groups and nutrients (dairy, fats, fruits, vegetables, legumes, and animal-derived protein sources), and the risk of endometriosis among adult women. PubMed, Scopus, and ISI Web of Science were systematically searched up to September 2022. The inverse variance-weighted fixed-effect method was used to estimate the effect size and corresponding 95% CI. A total of 8 publications (4 studies) including 5 cohorts and 3 case-control with a sample size ranging from 156 to 116,607 were included in this study. A higher intake of total dairy [all low-fat and high-fat dairy foods] was associated with decreased risk of endometriosis (RR 0.90; 95% CI, 0.85 to 0.95; P < 0.001; I² = 37.0%), but these associations were not observed with intakes of low or high-fat dairy, cheese or milk. Increased risk of endometriosis was associated with higher consumption of red meat (RR 1.17; 95% CI, 1.08 to 1.26; P < 0.001; I² = 82.4%), trans fatty acids (TFA) (RR 1.12; 95% CI, 1.02 to 1.23; P = 0.019; I² = 73.0%), and saturated fatty acids (SFA) (RR 1.06; 95% CI, 1.04 to 1.09; P < 0.001; I² = 57.3%). The results of this meta-analysis suggest that there may be differing associations between dietary intake of dairy foods, red meat, SFAs, and TFAs and the risk of endometriosis. It may be useful to extend the analysis to other types of food groups and dietary patterns to obtain a complete picture. Additionally, further investigations are needed to clarify the role of diet in the incidence and progression of endometriosis.Trial registration: PROSPERO, CRD42020203939.

The Burden of Cancer, Government Strategic Policies, and Challenges in Pakistan: A Comprehensive Review

Cancer is a severe condition characterized by uncontrolled cell division and increasing reported mortality and diagnostic cases. In 2040, an estimated 28.4 million cancer cases are expected to happen globally. In 2020, an estimated 19.3 million new cancer cases (18.1 million excluding non-melanoma skin cancer) had been diagnosed worldwide, with around 10.0 million cancer deaths. Breast cancer cases have increased by 2.26 million, lung cancer by 2.21 million, stomach by 1.089 million, liver by 0.96 million, and colon cancer by 1.93 million. Cancer is becoming more prevalent in Pakistan, with 19 million new cancer cases recorded in 2020. Food adulteration, gutkha, paan, and nutritional deficiencies are major cancer risk factors that interplay with cancer pathogenesis in this country. Government policies and legislation, cancer treatment challenges, and prevention must be revised seriously. This review presents the current cancer epidemiology in Pakistan to better understand cancer basis. It summarizes current cancer risk factors, causes, and the strategies and policies of the country against cancer.

Effect of Dietary-Based Lifestyle Modification Approaches on Anthropometric Indices and Dietary Intake Parameters in Women with Breast Cancer: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

This systematic review and meta-analysis aimed to investigate the effect of dietary-based lifestyle modification interventions ("diet," or "diet + exercise," or "diet + exercise + behavioral" intervention) on the measures of anthropometric and dietary intake parameters in women with breas cancer (BC). Databases were searched until June 2021. Inclusion criteria were randomized controlled trials that enrolled only women with BC. Studies that used exercise or behavioral interventions alone were not included. Mean ± SD changes were extracted for each outcome, and pooled using a random-effects model; 7315 studies were identified. Fifty-one studies (n = 7743) were included. The median ± SD duration of treatment was 24 ± 16.65 wk. Dietary-based interventions significantly reduced body weight [45 studies (n = 7239), weighted mean difference (WMD) (95% CI): -2.6 (-3.2, -2.1) kg], BMI [31 studies (n = 5384); WMD (95% CI): -1.0 (-1.3, -0.7) kg/m2], lean body mass [15 studies (n = 1194); WMD (95% CI): -0.6(-0.7, -0.4) kg], fat mass [11 studies (n = 913); WMD (95% CI): -2.6 (-3.3, -1.8) kg], fat percentage [17 studies (n = 897); WMD (95% CI): -1.5 (-1.9, -1.3)%], hip circumference [9 studies (n = 489); WMD (95% CI): -2.43 (-3.34, -1.54) cm], and waist circumference [7 studies (n = 309); WMD (95% CI): 0.02 (-0.03, -0.005) cm]. Significant reductions in energy intakes [20 studies (n = 4608), WMD (95% CI): -162 (-220, 104) kcal/d] and fat intakes [7 studies (n = 4316), WMD (95% CI): -7.5 (-7.8, -7.2)% of energy/d], and an increase in fiber intakes [11 studies (n = 4241), WMD (95% CI): 2.4 (0.7, 4.1) g/d] were observed. No significant changes were seen in protein, carbohydrate, and fruit and vegetable intakes. Subgroup analyses showed that changes in anthropometric and dietary intake indices were significant in studies that enrolled patients with both obesity and normal weight, studies that used diet therapy in combination with exercise and behavioral therapy, and studies that started the intervention during the treatment period. Overall, a multimodal dietary-based lifestyle intervention had significant effects on anthropometric and dietary intake parameters in women with BC, specifically when started as early as the diagnosis. This meta-analysis was registered at PROSPERO as CRD42021291488.

Consumption of dairy products and odds of breast cancer: an Iranian case-control study

BACKGROUND

Data on the link between total and individual dairy product consumption and risk of breast cancer are controversial, especially in Middle Eastern populations.

OBJECTIVE

This study aimed to evaluate the association between total and individual dairy product consumption and odds of breast cancer among Iranian women.

METHODS

In the context of a population-based case-control study on 350 patients with pathologically confirmed cases of breast cancer and 700 age-matched controls, we assessed dietary intakes using a 106-item semi-quantitative dish-based food frequency questionnaire. Consumption of low- and high-fat dairy products as well as dietary intakes of pasteurized milk, cheese and yogurt were computed.

RESULTS

Mean (± SD) age and BMI of study participants was 62.4 ± 10.8 y and 24.3 ± 5.2 kg/m², respectively. After controlling for potential covariates, individuals in the top quartile of low-fat dairy product intake were less likely to have breast cancer than those in the bottom quartile (OR 0.08; 95% CI 0.05-0.16), while those with the highest intake of high-fat dairy intake had greater odds for breast cancer than those with the lowest intake (OR 8.62; 95% CI 4.78-15.55). Despite lack of a significant association between yogurt and cheese consumption and odds of breast cancer, we found a positive association between total milk intake (OR 1.76; 95% CI 1.16-2.65) and breast cancer, after controlling for potential confounders.

CONCLUSION

Low-fat dairy intake was inversely and high-fat dairy consumption was positively associated with breast cancer. No significant association was found between yogurt and cheese consumption and breast cancer, while total milk intake was associated with a greater odds of breast cancer.

Dietary Fat and Polyunsaturated Fatty Acid Intakes during Childhood Are Prospectively Associated with Puberty Timing Independent of Dietary Protein

Dietary fat and fat quality have been inconsistently associated with puberty timing. The aim of this study was to investigate the prospective associations of dietary fat, saturated fatty acid (SFA), polyunsaturated fatty acid (PUFA), and monounsaturated fatty acid (MUFA) with puberty timing. Using longitudinal data from China Health and Nutrition Survey (CHNS) and Southwest China Childhood Nutrition and Growth (SCCNG) Study, we analyzed dietary data, anthropometric measurements, and potential confounders. Dietary intakes were assessed by 3-day 24-h recalls. Age at Tanner stage 2 for breast/genital development (B2/G2) and age at menarche/voice break (M/VB) were used as puberty development markers. Cox proportional hazard regression models were used to estimate the relevance of dietary intake of total fat, SFA, PUFA, and MUFA on puberty timing. Among 3425 girls and 2495 boys, children with higher intakes of total fat and PUFA were more likely to reach their B2/G2 or M/VB at an earlier age. Associations were not attenuated on additional adjustment for childhood dietary protein intake. However, higher intakes of SFA or MUFA were not independently associated with puberty development. A higher intake of dietary fat and PUFA in prepuberty was associated with earlier puberty timing, which was independent of dietary protein intake.

Dietary Factors and Breast Cancer Prognosis among Breast Cancer Survivors: A Systematic Review and Meta-Analysis of Cohort Studies

Simple Summary

While most systematic reviews have focused on the association between dietary factors and breast cancer incidence, this current study focuses on the association between comprehensive dietary factors and breast cancer prognosis among breast cancer survivors by systematic review and meta-analysis. We reviewed a total of 63 cohort studies to assess the association between dietary factors and breast cancer prognosis by subgroup analysis with prediagnostic or postdiagnostic dietary intake, menopausal status, and dietary or supplementary micronutrient intake. We found that unhealthy dietary patterns, including the intake of beer and saturated fat, exacerbated the risk of breast cancer prognosis; however, the supplementation of most vitamins was desirable for breast cancer prognosis. Therefore, this study’s systematic review and meta-analysis provide useful dietary information for the development of dietary guidelines/recommendations to improve prognosis among breast cancer survivors.

Abstract

Few studies have summarized the association between dietary factors and breast cancer (BC) prognosis among breast cancer survivors (BCS). Therefore, we carried out a systematic review and meta-analysis to determine the associations between dietary factors and BC prognosis among BCS. We performed a literature search in PubMed and Embase to investigate the association between dietary factors and BC prognosis. We applied a random-effects model to compute the hazard ratio/relative risk and their 95% confidence intervals and heterogeneity (Higgins I²) and to generate forest plots using STATA. Among the 2279 papers identified, 63 cohort studies were included in the systematic review and meta-analysis. Our main finding was that higher consumption of beer and saturated fat negatively affected BC prognosis. However, the intake of lignans, fiber, multivitamins, and antioxidants was negatively associated with the risk of mortality. Furthermore, we performed subgroup analyses by menopausal status and dietary or supplementary micronutrient intake. Most trends were similar to the main findings; in particular, the vitamin C, vitamin D, and vitamin E supplements decreased the risk of mortality. This study’s current systematic review and meta-analysis provide comprehensive dietary information for the development of dietary guidelines/recommendations to improve prognosis among BCS.

Association between dietary fat and fat subtypes with the risk of breast cancer in an Iranian population: a case-control study

AIM

To examine the relationship between dietary fat intake and breast cancer (BC) development.

METHOD

This case-control study included 473 women with breast cancer (pathologically confirmed) and 501 healthy subjects matched by age and residency. Dietary intakes of different types and sources of fatty acids were assessed using a validated food frequency questionnaire. The association between dietary fats and odds of BC was assessed using a logistic regression model in crude and multivariable-adjusted models. P values below 0.05 were regarded as statistically significant.

RESULTS

Participants' age and body mass index were 44.0 ± 10.8 years and 28.4 ± 5.6 kg/m2, respectively. Individuals with the highest quartile of total fat intake and polyunsaturated fatty acid (PUFA) intake were 1.50 times more at risk to develop BC than others. A positive significant association was observed between animal fat (Q4 vs. Q1, OR = 1.89, 95 % CI = 0.93-3.81), saturated fatty acid (SFA) (Q4 vs. Q1, OR = 1.70, 95 % CI = 0.88-3.30), monounsaturated fatty acid (MUFA) (Q4 vs. Q1 OR = 1.85, 95 % CI = 0.95-3.61) and PUFA intake (Q4 vs. Q1, OR = 2.12, 95 % CI = 1.05-4.27) with BC risk in postmenopausal women. However, there was no association in premenopausal women.

CONCLUSIONS

Total dietary fat and its subtypes might increase the risk of BC, especially in postmenopausal women. This observational study confirms the role of dietary fat in breast cancer development. Intervention studies involving different estrogen receptor subgroups are needed.

Evidence-based tailored nutrition educational intervention improves adherence to dietary guidelines, anthropometric measures and serum metabolic biomarkers in early-stage breast cancer patients: A prospective interventional study

PURPOSE

The impact of the adherence to dietary guidelines of early-stage breast cancer (EBC) patients on body composition changes during treatment is not entirely defined. This study aimed to evaluate the role of an evidence-based nutrition educational intervention, according to adherence to dietary guidelines, in EBC patients.

METHODS

This prospective study included EBC patients, candidates for neoadjuvant/adjuvant therapy. Patients received an evidence-based tailored nutrition educational intervention. The adherence to dietary guidelines, anthropometric and dietary assessments, and blood glucose and lipid profile tests were evaluated at baseline and after a 12-months nutritional intervention.

RESULTS

Two hundred and forty-three patients were enrolled. At baseline, 38.3% and 23.9% of patients were overweight and obese, weight gain ≥5% (compared to 6-months before enrollment) and central obesity were observed in 47.3% and 52.7% of patients, respectively. Adherence to dietary guidelines was low (median Med-Diet score: 6 [IQR 4-8]). After the nutritional intervention (median follow-up: 22 months [range 12-45]), adherence to dietary guidelines significantly increased (median Med-Diet score: 12 [IQR 8-13]), p < 0.0001). High adherence to dietary guidelines (defines as Med-Diet score ≥10) significantly correlated with: 1) overall weight loss ≥5% (21.8% vs. 2.5%, p = 0.003); 2) median BMI drop (from 25.6 kg/m² to 24.4 kg/m², p = 0.003); 3) lower prevalence of central obesity (38.2% vs. 7.2%, p = 0.01); 4) improvement in blood glucose levels and lipid profile.

CONCLUSION

This study suggests that an evidence-based tailored nutrition educational intervention during treatment for EBC significantly increases overall adherence to dietary guidelines, and it improves both anthropometric measures and serum metabolic biomarkers in patients with high adherence.

No impact of developmental conditions on serum estradiol levels among Bangladeshi women in the UK and Bangladesh

INTRODUCTION

While many aspects of female ovarian function respond to environmental stressors, estradiol (E2) appears less sensitive to stressors than progesterone, except under extreme ecological conditions. However, earlier studies relied on saliva samples, considered less sensitive than blood. Here, we investigated E2 variation among 177 Bangladeshi and UK white women, aged 35-59, using single serum samples. Bangladeshi women either grew up in Sylhet, Bangladesh (exposed to poor sanitation, limited health care, and higher pathogen loads but not poor energy availability), or in the UK.

METHODS

We collected samples on days 4-6 of the menstrual cycle in menstruating women and on any day for post-menopausal women. Participants included: (i) Bangladeshi sedentees (n = 36), (ii) Bangladeshis who migrated to the UK as adults (n = 52), (iii) Bangladeshis who migrated as children (n = 40), and (iv) UK white women matched for neighborhood residence to the migrants (n = 49). Serum was obtained by venipuncture and analyzed using electrochemiluminescence. We collected anthropometrics and supplementary sociodemographic and reproductive data through questionnaires. We analyzed the data using multivariate regression.

RESULTS

E2 levels did not differ between migrant groups after controlling for age, BMI, physical activity, psychosocial stress, parity, and time since last birth (parous women). Paralleling results from salivary E2, serum E2 did not differ among women who experienced varying developmental conditions.

CONCLUSION

Our results reinforce the hypothesis that E2 levels are stable under challenging environmental conditions. Interpopulation variation may only arise under chronic conditions of extreme nutritional scarcity, energy expenditure, and/or high disease burdens.

Nutrition in Gynecological Diseases: Current Perspectives

Diet and nutrition are fundamental in maintaining the general health of populations, including women's health. Health status can be affected by nutrient deficiency and vice versa. Gene-nutrient interactions are important contributors to health management and disease prevention. Nutrition can alter gene expression, as well as the susceptibility to diseases, including cancer, through several mechanisms. Gynecological diseases in general are diseases involving the female reproductive system and include benign and malignant tumors, infections, and endocrine diseases. Benign diseases such as uterine fibroids and endometriosis are common, with a negative impact on women's quality of life, while malignant tumors are among the most common cause of death in the recent years. In this comprehensive review article, a bibliographic search was performed for retrieving information about nutrients and how their deficiencies can be associated with gynecological diseases, namely polycystic ovary syndrome, infertility, uterine fibroids, endometriosis, dysmenorrhea, and infections, as well as cervical, endometrial, and ovarian cancers. Moreover, we discussed the potential beneficial impact of promising natural compounds and dietary supplements on alleviating these significant diseases.

Uterine Fibroids and Diet

Uterine myomas or fibroids are the most common benign female tumors of the reproductive organs, associated with significant morbidity and quality of life impairment. Several epidemiological risk factors for their occurrence have been identified so far, including nutrition and dietary habits. In this investigation, authors reviewed, as a narrative review, the data about diet and uterine myoma development in order to homogenize the current data. A PubMed search was conducted for the years 1990–2020, using a combination of keywords of interest for the selected topic. The authors searched the databases, selecting the randomized clinical studies, the observational studies, and the basic (experimental), clinical, and epidemiological researches. Once they collected the articles, they analyzed them according to the number of citations of each article, starting from the most cited to the least cited articles. Subsequently, authors collected the data of each article and inserted them in the various research paragraphs, summarizing the data collected. In this way, they crossed the available data regarding the association between nutrition habits and dietary components and myoma onset and growth. Many nutrients and dietary habits are associated with myoma development risk. These factors include low intakes of fruit, vegetables, and vitamin D, as well as pollutants in food. Despite the available data on the influence of some foods on the development of fibroids, further research is mandatory to understand all the nutrition risk factors which contribute to myoma growth and how exactly these risk factors influence myoma pathogenesis.

Dietary fat intake, erythrocyte fatty acids, and risk of uterine fibroids

OBJECTIVE

To prospectively evaluate the association between dietary fat intake and risk of uterine fibroids; and to evaluate the association between erythrocyte membrane fatty acid (FA) levels and fibroid risk.

DESIGN

Prospective cohort study. Cox proportional hazard models were used to calculate hazard ratios and 95% confidence interval (CI). In a subset of participants 34 individual FAs were measured and logistic regression analysis was used to estimate odds ratios (ORs) and 95% CI for the association between FA tertiles and fibroids.

SETTING

Not applicable.

PATIENT(S)

Premenopausal US women (81,590) in the Nurses' Health Study II, aged 25-42 years at enrollment in 1989 for whom diet was assessed by a food frequency questionnaire. A total of 553 participants with erythrocyte FA measurements.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Cases of fibroids were defined on the basis of self-reported ultrasound or hysterectomy confirmation.

RESULT(S)

A total of 8,142 cases of ultrasound-confirmed or hysterectomy-confirmed were diagnosed during an 18-year period (1991-2009). No associations were observed between intake of any dietary fats and fibroids in the multivariable models. However, when erythrocyte FAs were examined, an inverse association was observed between total n-3 polyunsaturated FAs and likelihood of fibroids (OR for third versus first tertile, 0.41; 95% CI 0.19-0.89). In addition, total trans FAs were associated with more odds of fibroids (OR for third tertile, 3.33; 95% CI 1.50-7.38).

CONCLUSION(S)

Our findings provide preliminary suggestions that n-3 polyunsaturated FAs and trans FAs may play a role in fibroid etiology; however, these results should be confirmed in future studies.

Nutrient-wide association study of 92 foods and nutrients and breast cancer risk

BACKGROUND

Several dietary factors have been reported to be associated with risk of breast cancer, but to date, unequivocal evidence only exists for alcohol consumption. We sought to systematically assess the association between intake of 92 foods and nutrients and breast cancer risk using a nutrient-wide association study.

METHODS

Using data from 272,098 women participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study, we assessed dietary intake of 92 foods and nutrients estimated by dietary questionnaires. Cox regression was used to quantify the association between each food/nutrient and risk of breast cancer. A false discovery rate (FDR) of 0.05 was used to select the set of foods and nutrients to be replicated in the independent Netherlands Cohort Study (NLCS).

RESULTS

Six foods and nutrients were identified as associated with risk of breast cancer in the EPIC study (10,979 cases). Higher intake of alcohol overall was associated with a higher risk of breast cancer (hazard ratio (HR) for a 1 SD increment in intake = 1.05, 95% CI 1.03-1.07), as was beer/cider intake and wine intake (HRs per 1 SD increment = 1.05, 95% CI 1.03-1.06 and 1.04, 95% CI 1.02-1.06, respectively), whereas higher intakes of fibre, apple/pear, and carbohydrates were associated with a lower risk of breast cancer (HRs per 1 SD increment = 0.96, 95% CI 0.94-0.98; 0.96, 95% CI 0.94-0.99; and 0.96, 95% CI 0.95-0.98, respectively). When evaluated in the NLCS (2368 cases), estimates for each of these foods and nutrients were similar in magnitude and direction, with the exception of beer/cider intake, which was not associated with risk in the NLCS.

CONCLUSIONS

Our findings confirm a positive association of alcohol consumption and suggest an inverse association of dietary fibre and possibly fruit intake with breast cancer risk.

Animal foods and postmenopausal breast cancer risk: a prospective cohort study

The role of diet on breast cancer risk is not well elucidated but animal food sources may play a role through, for example, the pathway of the insulin-like growth factor 1 system or cholesterol metabolism. The aim of this study was to evaluate the association between animal foods and the risk of postmenopausal breast cancer. This study was embedded in the Rotterdam Study, a population-based prospective cohort study of subjects aged 55 years and over (61 % female). Dietary intake of different animal foods was assessed at baseline using a validated FFQ and adjusted for energy intake using the residual method. We performed Cox proportional hazards modelling to analyse the association between the intake of the different food sources and breast cancer risk after adjustment for socio-demographic, lifestyle and metabolic factors. During a median follow-up of 17 years, we identified 199 cases of breast cancer (6·2 %) among 3209 women. After adjustment for multiple confounders, no consistent association was found between the intake of red meat intake, poultry, fish or dairy products and breast cancer risk. However, we found that egg intake was significantly associated with a higher risk of breast cancer (hazard ratioQ4 v. Q1: 1·83; 95 % CI 1·20, 2·79; Ptrend=0·01). In conclusion, this study found that dietary egg intake but no other animal foods was associated with a higher risk of postmenopausal breast cancer. Further research on the potential mechanisms underlying this association is warranted.

Low-saturated-fat and low-cholesterol diet does not alter pubertal development and hormonal status in adolescents

Aim

The aim was to assess the influence of dietary counselling on the pubertal development and hormonal status in healthy adolescents.

Methods

We used a subcohort of 193 healthy boys (52%) and girls (48%) from the Special Turku Coronary Risk Factor Intervention Project. Participants were recruited by nurses at the well‐baby clinics in Turku Finland in 1990–1992 and randomised into intervention and control groups. Intervention children received low‐saturated fat and low‐cholesterol dietary counselling initiated at seven months of age. Participants were examined once a year with Tanner staging, anthropometric measurements and serial reproductive hormones from 10 to 19 years of age. In girls, postmenarcheal hormones were not analysed.

Results

Pubertal hormones in boys or girls did not differ between the intervention and control groups. However, we observed slight differences in pubertal progression by Tanner staging and in anthropometric parameters. The intervention boys progressed faster to G4 (p = 0.008), G5 (p = 0.008) and P5 (p = 0.03). The intervention boys were taller than control boys (p = 0.04), while weight and body mass index did not differ.

Conclusion

Dietary intervention did not affect pubertal hormonal status. This finding supports the safety of implemented counselling in respect to puberty.

Diet, menopause and the risk of ovarian, endometrial and breast cancer

Menopause, the permanent cessation of the menstrual cycle, marks the end of a woman's reproductive lifespan. In addition to changes in sex hormone levels associated with menopause, its timing is another predictor of future health outcomes such as duration of the presence of vasomotor symptoms (VMS) and the risk of hormone-related cancers. With ageing of the population, it is estimated that worldwide 1·2 billion women will be menopausal by the year 2030. Previously the effects of reproductive factors (e.g. parity, age at menarche, pregnancy) and socio-demographic factors on intermediate and long-term health outcomes of menopause have been widely documented. However, little is known about whether diet could have an impact on these. Therefore, we review current evidence on the associations of diet with menopause, presence of VMS and the risk of hormone-related cancers such as ovarian, endometrial and breast cancer. Dietary factors could influence the lifespan of the ovaries and sex-hormones levels, hence the timing of natural menopause. Few studies reported an association between diet, in particular soya consumption, and a reduced risk of VMS. Sustained oestrogen exposure has been associated with a higher risk of hormone-related cancers and thus high-fat and meat diets have been linked with an increased risk of these cancers. However, to better understand the mechanistic pathways involved and to make stronger conclusions for these relationships, further studies investigating the associations of dietary intakes and dietary patterns with menopause, presence of VMS and the risk of hormone-related cancers are required.

A prospective cohort study of meat and fish consumption and endometriosis risk

BACKGROUND

Only 2 case-control studies have examined the associations between consumption of meat products and endometriosis risk with inconsistent results. Consumption of animal products has the potential to influence endometriosis risk through effects on steroid hormones levels.

OBJECTIVE

We sought to determine whether higher intake of red meat, poultry, fish, and seafood are associated with risk of laparoscopically confirmed endometriosis.

STUDY DESIGN

A total of 81,908 participants of the prospective Nurses' Health Study II were followed up from 1991 through 2013. Diet was assessed via food frequency questionnaire every 4 years. Cox proportional hazards models were used to calculate rate ratios and 95% confidence intervals.

RESULTS

During 1,019,294 person-years of follow-up, 3800 cases of incident laparoscopically confirmed endometriosis were reported. Women consuming >2 servings/d of red meat had a 56% higher risk of endometriosis (95% confidence interval, 1.22-1.99; P_trend < .0001) compared to those consuming ≤1 serving/wk. This association was strongest for nonprocessed red meats (rate ratio, 1.57; 95% confidence interval, 1.35-1.83 for ≥2 servings/d vs ≤1 servings/wk; P_trend < .0001), particularly among women who had not reported infertility (P_interaction = .0004). Women in the highest category of processed red meat intake also had a higher risk of endometriosis (rate ratio, 1.20; 95% confidence interval, 1.06-1.37 for ≥5 servings/wk vs <1 serving/mo; P_trend = .02). Intakes of poultry, fish, shellfish, and eggs were unrelated to endometriosis risk.

CONCLUSION

Our prospective analysis among premenopausal US nurses suggests that red meat consumption may be an important modifiable risk factor for endometriosis, particularly among women with endometriosis who had not reported infertility and thus were more likely to present with pain symptoms. Well-designed dietary intervention studies among women with endometriosis could help confirm this observation.

Dietary intake and age at natural menopause: results from the UK Women's Cohort Study

BACKGROUND

Age at natural menopause is a matter of concern for women of reproductive age as both an early or late menopause may have implications for health outcomes.

METHODS

Study participants were women aged 40-65 years who had experienced a natural menopause from the UK Women's Cohort Study between baseline and first follow-up. Natural menopause was defined as the permanent cessation of menstrual periods for at least 12 consecutive months. A food frequency questionnaire was used to estimate diet at baseline. Reproductive history of participants was also recorded. Regression modelling, adjusting for confounders, was used to assess associations between diet and age at natural menopause.

RESULTS

During the 4-year follow-up period, 914 women experienced a natural menopause. A high intake of oily fish and fresh legumes were associated with delayed onset of natural menopause by 3.3 years per portion/day (99% CI 0.8 to 5.8) and 0.9 years per portion/day (99% CI 0.0 to 1.8), respectively. Refined pasta and rice was associated with earlier menopause (per portion/day: -1.5 years, 99% CI -2.8 to -0.2). A higher intake of vitamin B6 (per mg/day: 0.6 years, 99% CI 0.1 to 1.2) and zinc (per mg/day: 0.3 years, 99% CI -0.0 to 0.6) was also associated with later age at menopause. Stratification by age at baseline led to attenuated results.

CONCLUSION

Our results suggest that some food groups (oily fish, fresh legumes, refined pasta and rice) and specific nutrients are individually predictive of age at natural menopause.

Dietary fat intake and ovarian cancer risk: a meta-analysis of epidemiological studies

Observational studies assessing the association of dietary fat and risk of ovarian cancer yield discrepant results. Pertinent prospective cohort studies were identified by a PubMed search from inception to December 2015. Sixteen independent case-control and nine cohort studies on dietary fat intake were included, with approximately 900,000 subjects in total. Relative risks (RRs) with 95% confidence intervals were pooled using a random effects model. Heterogeneity, sensitivity analysis and publication bias were assessed; subgroup analysis and analysis stratified by EOC histology were conducted. The reported studies showed a significant increase of ovarian cancer risk with high consumption of total-, saturated-, and trans-fats, while serous ovarian cancer was more susceptible to dietary fat consumption than other pathological subtypes. No evidence of positive association between dietary fat intake and ovarian cancer risk was provided by cohort studies. Menopausal status, hormone replacement therapy, body mass index (BMI), and pregnancy times, modified the objective associations. In conclusion, the meta-analysis findings indicate that high consumption of total, saturated and trans-fats increase ovarian cancer risk, and different histological subtypes have different susceptibility to dietary fat.

Macronutrient intakes and serum oestrogen, and interaction with polymorphisms in CYP19A1 and HSD17B1 genes: a cross-sectional study in postmenopausal Japanese women

Although higher circulating levels of oestrogen are related to postmenopausal breast cancer risk, limited information is available regarding effects of diet on endogenous oestrogen. Thus, we examined associations between macronutrient intakes and serum oestrogen with consideration of polymorphisms in oestrogen-metabolising genes. In this cross-sectional study, 784 naturally menopaused Japanese women aged 47–69 years were selected from participants of the Japan Multi-Institutional Collaborative Cohort Study. We documented dietary intakes, measured serum concentrations of oestrone (E1) and oestradiol (E2) and genotyped polymorphisms in oestrogen-metabolising CYP19A1 (rs4441215 and rs936306) and HSD17B1 (rs605059) genes. Trends and interactions were examined using linear regression models. In addition, we calculated the ratios of the oestrogen concentrations of the second to the highest quartiles (Q2–Q4) of dietary intake to those of the lowest quartiles (Q1). After adjustment for potential confounders, E2 was significantly associated with intake of carbohydrate and noodles; ratios of Q4 v. Q1 were 1·15 (95 % CI 1·04, 1·28) and 1·15 (95 % CI 1·04, 1·26), respectively. In contrast, E2 levels were inversely associated with intake of total energy, SFA and n-3 highly unsaturated fatty acids (n-3 HUFA); ratios of Q4 v. Q1 were 0·90 (95 % CI 0·82, 0·99), 0·89 (95 % CI 0·81, 0·98) and 0·91 (95 % CI 0·83, 1·00), respectively. In stratified analysis by polymorphisms, the rs605059 genotype of HSD17B1 significantly modified associations of E2 with intake of n-3 HUFA and fish; the associations were limited to those with the CC genotype. Macronutrient intakes were associated with serum E2 level, and these associations may be modified by HSD17B1 polymorphism in postmenopausal women.

"What about diet?" A qualitative study of cancer survivors' views on diet and cancer and their sources of information

Given the abundance of misreporting about diet and cancer in the media and online, cancer survivors are at risk of misinformation. The aim of this study was to explore cancer survivors' beliefs about diet quality and cancer, the impact on their behaviour and sources of information. Semi-structured interviews were conducted with adult cancer survivors in the United Kingdom who had been diagnosed with any cancer in adulthood and were not currently receiving treatment (n = 19). Interviews were analysed using Thematic Analysis. Emergent themes highlighted that participants were aware of diet affecting risk for the development of cancer, but were less clear about its role in recurrence. Nonetheless, their cancer diagnosis appeared to be a prompt for dietary change; predominantly to promote general health. Changes were generally consistent with healthy eating recommendations, although dietary supplements and other non-evidence-based actions were mentioned. Participants reported that they had not generally received professional advice about diet and were keen to know more, but were often unsure about information from other sources. The views of our participants suggest cancer survivors would welcome guidance from health professionals. Advice that provides clear recommendations, and which emphasises the benefits of healthy eating for overall well-being, may be particularly well-received.

Liver Cancer Mortality and Food Consumption in Serbia, 1991-2010: An Ecological Study

AIM

This paper investigates the correlation between liver cancer mortality and consumption of food-groups in Serbia.

METHODS

We conducted an ecological study. The study comprised the population of the Republic of Serbia (about 7.5 million inhabitants) during the period 1991-2010. This ecological study included the data on food consumption per capita which were obtained by the Household Budget Survey and mortality data for liver cancer made available by the National Statistical Office. Linear trend model was used to assess a trend of age-adjusted liver cancer mortality rates (per 100,000 persons) that were calculated by the method of direct standardization using the World Standard Population. Pearson correlation was performed to examine the association between liver cancer mortality and per capita food consumption quantified with a correlation coefficient (r value).

RESULTS

In Serbia, over the past two decades a significantly decreasing trend of liver cancer mortality rates has been observed (p<0.001). Liver cancer mortality was significantly (p<0.01) positively correlated with animal fat, beef, wine and spirits intake (r=0.713, 0.631, 0.632 and 0.745, respectively). A weakly positive correlation between milk consumption and mortality from liver cancer (r=0.559, p<0.05) was found only among women. The strongest correlation was found between spirits consumption and liver cancer mortality rates in women (r=0.851, p<0.01). A negative correlation between coffee consumption and age-adjusted liver cancer mortality rates was found (r=0.516, p<0.05) only for the eldest men (aged 65 years or older).

CONCLUSIONS

Correlations between liver cancer and dietary habits were observed and further effort is needed in order to investigate a possible causative association, using epidemiological analytical studies.

Plasma phospholipids fatty acids, dietary fatty acids, and breast cancer risk

PURPOSE

This study prospectively investigates associations between fatty acids assessed in plasma phospholipids (PPL) and diet, and breast cancer risk, including subgroups defined by hormone receptor status.

METHODS

We performed a case-cohort analysis within the Melbourne Collaborative Cohort Study using a random sample of 2,021 women and 470 breast cancer cases. At baseline, fatty acids were assessed in PPL and estimated from diet using a 121-item food frequency questionnaire. Hazard ratios (HR) and 95 % confidence intervals (CI) were estimated using Cox regression.

RESULTS

Breast cancer risk was positively associated with %PPL saturated fatty acids (SFA); HRQ5vsQ1 = 1.64 (95 % CI 1.17-2.30); p trend = 0.004. Positive associations were found for ER+ or PR+ tumors for %PPL SFA and palmitic acid and for ER-/PR- tumors for %PPL n-6 polyunsaturated fatty acid (PUFA), TFA, TFA 16:1, and TFA 18:1n-7 (all p homogeneity <0.05). Breast cancer risk was inversely associated with dietary docosapentaenoic acid (DPA); HRQ5vsQ1 = 0.57 (95 % CI 0.40-0.82); p trend = 0.001 [with similar inverse associations observed for dietary docosahexaenoic (DHA) and eicosapentaenoic acid (EPA)] and positively associated with dietary n-6:n-3 PUFA. Inverse associations for ER-/PR- tumors were found for dietary dihomo-γ-linolenic acid (DGLA) for older women (p homogeneity = 0.04).

CONCLUSIONS

Breast cancer risk was positively associated with %PPL SFA and the ratio of dietary n-6 to n-3 PUFA and inversely associated with dietary long-chain n-3 PUFA intake. Some associations between fatty acids and breast cancer varied by age and tumor phenotype defined by hormone receptor status. Increased intake of fish and other foods rich in long-chain n-3 PUFAs and reduced n-6 PUFA intake might reduce breast cancer risk.

Dietary Patterns and Plasma Sex Hormones, Prolactin, and Sex Hormone-Binding Globulin in Premenopausal Women

BACKGROUND

Sex hormones are important for breast cancer, but it is unclear whether dietary patterns influence hormone concentrations.

METHODS

Dietary pattern adherence scores for the alternate Mediterranean diet (aMED), Dietary Approaches to Stop Hypertension (DASH), and Alternative Healthy Eating Index (AHEI) were calculated from semiquantitative food frequency questionnaires administered in 1995 and 1999. Premenopausal plasma concentrations of sex hormones were measured in samples collected in 1996 to 1999. We used generalized linear models to calculate geometric mean hormone concentrations across quartiles of dietary pattern scores among 1,990 women in the Nurses' Health Study II.

RESULTS

We did not observe significant associations between sex hormone concentrations and the DASH pattern and only one suggestive association between follicular estrone concentrations and the aMED pattern [top vs. bottom quartile -4.4%, 95% confidence interval (CI), -10.6% to 2.1%; Ptrend = 0.06]. However, women in the top versus bottom quartile of AHEI score had lower concentrations of follicular (-9.1%; 95% CI, -16.1% to -1.4%; Ptrend = 0.04) and luteal (-7.5%; 95% CI, -13.6% to -0.9%; Ptrend = 0.01) estrone, luteal-free (-9.3%; 95% CI, -16.8% to -1.1%; Ptrend = 0.01) and total (-6.7 %; 95% CI, -14.3% to 1.5%; Ptrend = 0.04) estradiol, follicular estradiol (-14.2%; 95% CI, -24.6% to -2.4%; Ptrend = 0.05), and androstenedione (-7.8%; 95% CI, -15.4% to 0.4%; Ptrend = 0.03).

CONCLUSION

Diet quality measured by the AHEI is inversely associated with premenopausal estrogen concentrations. Given that we did not observe similar associations with the aMED or DASH patterns, our findings should be interpreted with caution.

IMPACT

Given the role of estrogens in breast cancer etiology, our findings add to the substantial evidence on the benefits of adhering to a healthy diet. Cancer Epidemiol Biomarkers Prev; 25(5); 791-8. ©2016 AACR.

Adolescent intake of animal fat and red meat in relation to premenopausal mammographic density

Adolescence is hypothesized to be a time period of particular susceptibility to breast cancer risk factors. Red meat and fat intake during high school was positively associated with risk of breast cancer among premenopausal women in the Nurses' Health Study II (NHSII). High mammographic density is a strong predictor of breast cancer risk but there is limited research on dietary factors associated with breast density. To test the hypothesis that high intake of animal fat or red meat during adolescence is associated with mammographic density, we analyzed data from premenopausal women in the NHSII. Participants recalled adolescent diet on a high school food frequency questionnaire. We assessed absolute and percent mammographic density on digitized analog film mammograms for 687 premenopausal women with no history of cancer. We used generalized linear regression to quantify associations of adolescent animal fat and red meat intake with mammographic density, adjusting for age, body mass index, and other predictors of mammographic density. Adolescent animal fat intake was significantly positively associated with premenopausal mammographic density, with a mean percent density of 39.2 % in the lowest quartile of adolescent animal fat intake versus 43.1 % in the highest quartile (p trend: 0.03). A non-significant positive association was also observed for adolescent red meat intake (p trend: 0.14). These findings suggest that higher adolescent animal fat intake is weakly associated with percent mammographic density in premenopausal women.

Nutrient-wide association study of 57 foods/nutrients and epithelial ovarian cancer in the European Prospective Investigation into Cancer and Nutrition study and the Netherlands Cohort Study

BACKGROUND

Studies of the role of dietary factors in epithelial ovarian cancer (EOC) development have been limited, and no specific dietary factors have been consistently associated with EOC risk.

OBJECTIVE

We used a nutrient-wide association study approach to systematically test the association between dietary factors and invasive EOC risk while accounting for multiple hypothesis testing by using the false discovery rate and evaluated the findings in an independent cohort.

DESIGN

We assessed dietary intake amounts of 28 foods/food groups and 29 nutrients estimated by using dietary questionnaires in the EPIC (European Prospective Investigation into Cancer and Nutrition) study (n = 1095 cases). We selected 4 foods/nutrients that were statistically significantly associated with EOC risk when comparing the extreme quartiles of intake in the EPIC study (false discovery rate = 0.43) and evaluated these factors in the NLCS (Netherlands Cohort Study; n = 383 cases). Cox regression models were used to estimate HRs and 95% CIs.

RESULTS

None of the 4 dietary factors that were associated with EOC risk in the EPIC study (cholesterol, polyunsaturated and saturated fat, and bananas) were statistically significantly associated with EOC risk in the NLCS; however, in meta-analysis of the EPIC study and the NLCS, we observed a higher risk of EOC with a high than with a low intake of saturated fat (quartile 4 compared with quartile 1; overall HR: 1.21; 95% CI: 1.04, 1.41).

CONCLUSION

In the meta-analysis of both studies, there was a higher risk of EOC with a high than with a low intake of saturated fat.

Diets High in Fiber and Vegetable Protein Are Associated with Low Lumbar Bone Mineral Density in Young Athletes with Oligoamenorrhea

BACKGROUND

Associations of bone mineral density (BMD) with specific food components, including dietary fiber and isoflavones (that have a negative association with serum estrogen), are unclear and need to be determined, particularly in populations more likely to consume large amounts of these nutrients (such as young athletes).

OBJECTIVE

To determine dietary intake of specific food components in athletes with oligoamenorrhea (OA) compared to athletes with eumenorrhea (EA) and nonathletes (NA), and associations of the dietary intake of these nutrients with lumbar spine BMD.

DESIGN AND SUBJECTS

This cross-sectional study evaluated 68 OA, 24 EA, and 26 NA individuals aged 14 to 23 years. Measurements included 4-day food records, a dual x-ray absorptiometry scan evaluating lumbar spine BMD and body composition, and hormone levels. Multivariate analysis was used to estimate associations of nutrients with lumbar spine BMD.

RESULTS

Compared with EA and NA, OA had higher intake of fiber, phytic acid, and vegetable protein (all P values <0.0001). Intake of isoflavones, genistein, and daidzein was higher in OA than NA (P=0.003 and P=0.0002, respectively). OA had lower consumption of energy from saturated fatty acids than NA (P=0.002). After controlling for confounders such as body weight, menstrual status (indicative of estrogen status), calcium intake, and serum vitamin D (known BMD determinants), lumbar spine BMD z scores were inversely associated with dietary fiber (β=-.30; P=0.01), vegetable protein (β= -.28; P=0.02), phytic acid (β=-.27; P=0.02), genistein (β=-.25; P=0.01), and daidzein (β=-.24; P=0.01), and positively associated with percent energy from fatty acids (β=.32; P=0.0006).

CONCLUSIONS

Compared with EA and NA, OA had a higher dietary intake of fiber, vegetable protein, and phytic acid, which were inversely associated with lumbar spine BMD z scores. Further studies are needed to assess dietary recommendations for OA to optimize bone accrual.

Mediterranean diet for breast cancer prevention and treatment in postmenopausal women

Breast cancer has become a big oncological concern both in Poland and most countries around the world. Epidemiological studies show that women who are directly in danger of suffering from breast cancer are mainly postmenopausal women. Due to the seriousness of the problem more attention is devoted to preventative measures that should be undertaken. That is why, Mediterranean diet and its beneficial effects on health started to be discussed. This diet contains antioxidants and shows anti-inflammatory properties which are crucial in breast cancer prevention. Its components are fish, olive oil, unrefined cereals, herbs, fruits and vegetables. In 1960s there was research done on the influence of low fat diet, as a preventative measure, on coronary artery disease. In 1980s, an interest in this diet grew and there was a great come-back to the origins of the diet. It led to estimation of its influence on cardiological and cancer diseases. Many positive effects were observed among people living in the Mediterranean area as far as health qualities of the diet are concerned. Mediterranean diet was compared with high fat diet of people living in Northern Europe and the USA. It seems to create new dietary recommendations as a preventative measure in breast cancer disease. The following article presents most recent data on the importance of Mediterranean diet as a prevention against breast cancer.

Hippocampal learning, memory, and neurogenesis: Effects of sex and estrogens across the lifespan in adults

This article is part of a Special Issue "Estradiol and Cognition". There are sex differences in hippocampus-dependent cognition and neurogenesis suggesting that sex hormones are involved. Estrogens modulate certain forms of spatial and contextual memory and neurogenesis in the adult female rodent, and to a lesser extent male, hippocampus. This review focuses on the effects of sex and estrogens on hippocampal learning, memory, and neurogenesis in the young and aged adult rodent. We discuss how factors such as the type of estrogen, duration and dose of treatment, timing of treatment, and type of memory influence the effects of estrogens on cognition and neurogenesis. We also address how reproductive experience (pregnancy and mothering) and aging interact with estrogens to modulate hippocampal cognition and neurogenesis in females. Given the evidence that adult hippocampal neurogenesis plays a role in long-term spatial memory and pattern separation, we also discuss the functional implications of regulating neurogenesis in the hippocampus.

Weight loss increases follicle stimulating hormone in overweight postmenopausal women [corrected]

OBJECTIVES

To examine the impact of a weight loss intervention upon follicle stimulating hormone (FSH) levels in postmenopause.

METHODS

Participants were postmenopausal, overweight, glucose-intolerant women not using exogenous estrogen (n = 382) in the Diabetes Prevention Program. Women were randomized to intensive lifestyle change (ILS) with the goals of weight reduction of at least 7% of initial weight and 150 min per week of moderate-intensity exercise, metformin 850 mg twice a day, or placebo administered twice a day.

RESULTS

Randomization to ILS led to small increases in FSH between baseline and 1-year follow-up vs. placebo (2.3 IU/l vs. -0.81 IU/l, P < 0.01). Increases in FSH were correlated with decreases in weight (r = -0.165, P < 0.01) and estradiol (E2) (r = -0.464, P < 0.0001) after adjustment for age, race/ethnicity, and randomization arm. Changes in FSH were still significantly associated with changes in weight even after adjustment for E2 levels. Metformin users had reductions in weight but non-significant changes in FSH and E2 levels vs. placebo.

CONCLUSIONS

Weight loss leads to small increases in FSH among overweight, postmenopausal women, potentially through pathways mediated by endogenous estrogen as well as other pathways.

Dietary fat intake and risk of epithelial ovarian cancer in the European Prospective Investigation into Cancer and Nutrition

There are inconsistent and limited data available to assess the relationship between fat intake and risk of epithelial ovarian cancer (EOC). We examined the consumption of total fat, fat sources and fat subtypes in relation to risk of EOC and its major histologic subtypes in the European Prospective Investigation into Cancer and Nutrition which includes incident invasive (n=1095) and borderline (n=96) EOC. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). In multivariate models, we observed no association with consumption of total fat, animal or plant fat, saturated fat, cholesterol, monounsaturated fat, or fatty fish and risk of invasive EOC. There was, however, an increased risk of invasive EOC in the highest category of intake (Quartile 4 vs. Quartile 1) of polyunsaturated fat (HR=1.22, 95% CI=1.02-1.48, P(trend)=0.02). We did not observe heterogeneity in the risk associations in comparisons of serous and endometrioid histologic subtypes. This study does not support an etiological role for total fat intake in relation to EOC risk; however, based on observations of a positive association between intake of polyunsaturated fat and invasive EOC risk in the current and previous studies, this fat subtype warrants further investigation to determine its potential role in EOC development.

Effects of lifestyle modification after breast cancer treatment: a systematic review protocol

BACKGROUND

There is no consensus in the literature regarding the effectiveness of lifestyle modification interventions, including recommendations about specific diet or exercise program for patients with breast cancer. Diet interventions and regular physical activity may reduce the risk of breast cancer and its recurrence. The primary aim of our study is to evaluate the effects of different lifestyle modification interventions (diet and physical activity) in the survival of patients with stages I to III breast cancer after treatment.

METHODS/DESIGN

This review will be conducted according to the Cochrane Handbook for Systematic Reviews of Intervention and will be reported following the PRISMA statement recommendations. CENTRAL, MEDLINE and EMBASE databases will be searched for peer-reviewed literature. Randomized controlled trials of diet, exercise, or both, compared with usual care, after treatment of breast cancer stage I to III will be included in the systematic review. Two authors will independently screen titles and abstracts of studies for potential eligibility. Data will be combined using random-effect meta-analysis models with restricted maximum-likelihood as variance estimator, and will be presented as relative risk or standardized mean difference with 95% CI. The quality of evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework and summary of findings tables will be presented for patient important outcomes.

DISCUSSION

Our study may improve the current understanding of the role that lifestyle-modifiable factors can play in saving or prolonging the lives of women who have been treated for breast cancer, and also on modifying their quality of life.

SYSTEMATIC REVIEW REGISTRATION

The review has been registered with PROSPERO (registration number CRD42014008743).

Prospective study of dietary fat and risk of uterine leiomyomata

BACKGROUND

Uterine leiomyomata (UL) are the primary indication for hysterectomy and are 2-3 times more common in black than white women. High dietary fat intake has been associated with increased endogenous concentrations of estradiol, a sex steroid hormone that is known to influence UL risk.

OBJECTIVE

We assessed the relation of dietary fat intake (total, subtypes, and selected food sources) with UL incidence.

DESIGN

Data were from the Black Women's Health Study, a prospective cohort study. Over an 8-y period (2001-2009), 12,044 premenopausal women were followed for a first diagnosis of UL. Diet was assessed via a food-frequency questionnaire in 2001. Cox regression models were used to compute incidence rate ratios (IRRs) and 95% CIs with adjustment for potential confounders.

RESULTS

During 75,687 person-years of follow-up, there were 2695 incident UL cases diagnosed by ultrasound (n = 2191) or surgery (n = 504). Intakes of total fat and fat subtypes were not appreciably associated with UL risk overall, although statistically significant associations were observed for specific saturated (inverse) and monounsaturated and polyunsaturated (positive) fatty acids. With respect to polyunsaturated fats, the IRR for the highest compared with lowest quintiles of marine fatty acid intake [the sum of omega-3 (n-3) polyunsaturated fatty acids eicosapentanoic acid, docosapentaenoic acid, and docosahexaenoic acid] was 1.18 (95% CI: 1.05, 1.34; P-trend = 0.005). The IRR for the highest compared with lowest categories of dark-meat fish consumption was 1.13 (95% CI: 1.00, 1.28).

CONCLUSIONS

In US black women, the most consistent associations of fat intake with UL were small increases in risk associated with intakes of long-chain omega-3 fatty acids. Future studies are warranted to confirm these findings and elucidate which components of fatty foods, if any, are related to UL risk.

Dietary fat intake and risk of epithelial ovarian cancer by tumour histology

BACKGROUND

Studies of fat intake and epithelial ovarian cancer (EOC) risk have reported inconsistent findings, hence we hypothesised that associations may vary by histologic subtype.

METHODS

We evaluated fat intake in a New England case-control study including 1872 cases and 1978 population-based controls (1992-2008). Epithelial ovarian cancer risk factors and diet were assessed using a food frequency questionnaire at enrolment. Logistic regression was used to estimate associations between fat intake and EOC risk and polytomous logistic regression was used to test whether associations varied by histologic subtype.

RESULTS

We observed a decreased risk of EOC when comparing the highest vs lowest quartiles of intake of omega-3 (odds ratio (OR)=0.79, 95% confidence interval (CI) 0.66-0.96, P-trend=0.01) and omega-6 (OR=0.77, 95% CI 0.64-0.94, P-trend=0.02) and an increased risk with high consumption of trans fat (OR=1.30, 95% CI 1.08-1.57, P-trend=0.002). There was no significant heterogeneity by tumour histologic subtype; however, we observed a strong decreased risk for endometrioid invasive tumours with high intake of omega-3 (quartile (Q) 4 vs Q1, OR=0.58, 95% CI 0.41-0.82, P-trend=0.003).

CONCLUSIONS

These findings suggest that higher intake of omega-3 may be protective for EOC overall and endometrioid tumours in particular, whereas greater consumption of trans fat may increase risk of EOC overall.

Phytoestrogen and fiber intakes in relation to incident vasomotor symptoms: results from the Study of Women's Health Across the Nation

OBJECTIVE

Although reduction of vasomotor symptoms (VMS; hot flashes and night sweats) has been reported in postmenopausal women who used isoflavones, a clear dose response has not been shown, has largely not been reported for perimenopausal women, and has largely only been reported for reducing prevalent VMS, not preventing newly developing VMS. We analyzed longitudinal data from the Study of Women's Health Across the Nation for the relation of dietary phytoestrogen and fiber intake to incident VMS in this multiracial/ethnic cohort.

METHODS

The Study of Women's Health Across the Nation included 3,302 premenopausal and early perimenopausal women, 1,651 of whom reported no VMS at baseline and were followed with annual visits for 10 years. Dietary intakes of isoflavones, coumestrol, lignans, and fiber were assessed by a food frequency questionnaire at baseline and in annual visits 5 and 9 and interpolated for intervening years. The number of days experiencing VMS in the past 2 weeks was self-reported annually. Using multinomial logistic regression with generalized estimating equations, we modeled incident VMS in relation to isoflavones, lignans, fiber, coumestrol, or total phytoestrogen intake and covariates.

RESULTS

No consistent monotonic relations were observed between any dietary phytoestrogen or fiber and incident VMS, although adjusted odds ratios for some individual quartiles were statistically significant.

CONCLUSIONS

For certainty of any effect of dietary phytoestrogens or fiber on the prevention of incident VMS, a randomized, placebo-controlled, double-masked trial with sufficient numbers of women in different racial/ethnic, menopausal status, and metabolic groups over years of follow-up is required, but our results suggest that a clinically significant or large effect is improbable.

Association of vitamin B6, vitamin B12 and methionine with risk of breast cancer: a dose-response meta-analysis

Background:

Epidemiological studies evaluating the association of vitamin B₆, vitamin B₁₂ and methionine with breast cancer risk have produced inconsistent results.

Methods:

Pertinent studies were identified by a search in PubMed and Web of Knowledge. Random-effect model was used. Dose–response relationship was assessed by restricted cubic spline.

Results:

The combined relative risk (95% confidence interval) of breast cancer for the highest vs lowest category of serum pyridoxal 5′-phosphate (PLP, active form of vitamin B₆) levels and dietary methionine intake was 0.80 (0.66–0.98, P=0.03) and 0.94 (0.89–0.99, P=0.03), respectively, and the associations of breast cancer with higher serum PLP levels and dietary methionine intake were significant among post-menopausal women, but not among pre-menopausal women. The inverse association between breast cancer risk and dietary vitamin B₆ intake, serum vitamin B₁₂ levels and dietary vitamin B₁₂ intake was not significant overall. Linear dose–response relationship was found, and the risk of breast cancer decreased by 23% (P<0.00) for every 100 pmol ml⁻¹ increment in PLP levels and 4% (P=0.05) for every 1 g per day increment in dietary methionine intake, respectively.

Conclusion:

Serum PLP levels and methionine intake might be inversely associated with breast cancer risk, especially among postmenopausal women, which need to be confirmed.

Lipid profile among Moroccan overweight women and breast cancer: a case-control study

BACKGROUND

Breast cancer has become the most common type of cancer in Morocco. In 2005, 127 new cases in women, representing 33.5% of female cancers, were added to the National Center of Oncology registry. The incidence of breast cancer is higher in Morocco than in the three other Maghreb countries, and it is significantly lower than in Western countries where it stands at over 80 cases per 100,000 people.

PURPOSE

This 2-year long case-control study was conducted to assess the causal relationship between the lipid profile of overweight Moroccan women and breast cancer risk.

PATIENTS AND METHODS

Overweight female patients with breast cancer (n = 400) were compared to 400 healthy controls at the National Institute of Oncology of Rabat. The epidemiological data on the disease and physical activity were gathered by interviewing the patients who had their lipid profile measured (total cholesterol, triglycerides, high density lipoprotein cholesterol, and low density lipoprotein cholesterol). Body mass index was used to determine if patients were overweight.

RESULTS

Univariate analysis revealed a significant association between breast cancer and high body mass index (odds ratio [OR] = 1.31; 95% confidence interval [CI] = 1.25-1.37), menopause (OR = 2.68; 95% CI = 2-3.55), lack of physical activity (OR = 0.26; 95% CI = 0.21-0.31), and triglyceridemia (OR = 3.78; 95% CI = 2.73-5.23). Multivariate analysis revealed that the statistically significant increase in breast cancer risk was associated with a higher body mass index (OR = 1.11; 95% CI = 1.04-1.18), menopause (OR = 9.11; 95% CI = 4.76-17.47), and high triglyceride levels (OR = 4.5; 95% CI = 2.94-6.88). However, a protective effect for physical activity was detected (OR = 0.35; 95% CI = 0.26-0.48).

CONCLUSION

This study suggests that there is a connection between hypertriglyceridemia, obesity, and breast cancer risk and confirms a protective role for physical activity on breast cancer risk.

Evolutionary medicine and its implications for endocrinological issues (e.g. menopause)

Evolutionary medicine, which was formalized in the early 1990s, investigates evolutionary causes of recent human disease, disorders and malfunctions but also the influence of changing living conditions and modernization on health and disease. Evolutionary medicine can also provide insights into endocrinological disorders and in particular in the process of female reproductive senescence. Female reproductive senescence, i.e. menopausal transition is physiologically caused by the decline of estrogen secretion, which is associated with various somatic and psychic discomforts making this stage of life extremely uncomfortable. From the viewpoint of evolutionary medicine, these menopausal symptoms are the result from the sudden decrease of very high lifetime estrogen levels to zero during postmenopause, a situation which is quite new in our evolution and history. While women in recent developed countries experience menarche early, menopause late, few pregnancies, short periods of lactation and consequently low life time estrogen levels. The opposite is true of women living in traditional societies, whose living conditions may be interpreted as a mirror of the situation in our history. From this viewpoint we can conclude that menopausal symptoms may are the result of a mismatch between female reproductive physiology and recent living conditions.

Dietary fiber intake and risk of hormonal receptor-defined breast cancer in the European Prospective Investigation into Cancer and Nutrition study

BACKGROUND

Limited scientific evidence has characterized the association between dietary fiber intake and risk of breast cancer (BC) by menopausal status and hormone receptor expression in tumors.

OBJECTIVE

We investigated the relation between total dietary fiber and its main food sources (vegetables, fruit, cereals, and legumes) and BC risk by using data from the European Prospective Investigation into Cancer and Nutrition (EPIC).

DESIGN

A total of 11,576 invasive BC cases in 334,849 EPIC women mostly aged 35-70 y at baseline were identified over a median follow-up of 11.5 y. Dietary fiber was estimated from country-specific dietary questionnaires. Multivariable Cox proportional hazards regression models were used to quantify the association between dietary variables and BC risk with energy adjustment by using the residual method. Subgroup analyses were performed by menopausal status and estrogen receptor (ER) and progesterone receptor (PR) expression in tumors.

RESULTS

BC risk was inversely associated with intakes of total dietary fiber [hazard ratio comparing fifth quintile to first quintile (HR(Q5-Q1)): 0.95; 95% CI: 0.89, 1.01; P-trend = 0.03] and fiber from vegetables (0.90; 0.84, 0.96; P-trend < 0.01) but not with fiber from fruit, cereals, or legumes. Overall, associations were homogeneous by menopausal status and ER and PR expression in tumors. For vegetable fiber, stronger associations were observed for estrogen receptor-negative and progesterone receptor-negative (HR(Q5-Q1):0.74; 95% CI: 0.59, 0.93; P-trend = 0.01) than for estrogen receptor-positive and progesterone receptor-positive tumors (0.92: 0.81, 1.03; P-trend = 0.05), with P-heterogeneity = 0.09.

CONCLUSION

Diets rich in dietary fiber and, particularly, fiber from vegetables may be associated with a small reduction in risk of BC, independently of menopausal status.