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

Bread Consumption and Cancer Risk: Systematic Review and Meta-Analysis of Prospective Cohort Studies

Because bread can contain potential carcinogens such as acrylamide, and is widely consumed, we conducted a systematic review and meta-analysis to determine whether bread consumption is associated with increased cancer risk. PubMed and Medline databases were searched up to 1 March 2024, for studies that provided hazard ratios (HRs) (or similar) for bread consumption and cancer incidence or mortality. Only prospective cohort studies were included. We used the Preferred Reporting Items of Systematic reviews and Meta-Analyses checklist. Meta-analysis was performed with Cochrane's RevMan 5.4.1 software using a DerSimonian-Laird random-effects model. Heterogeneity was assessed with Cochrane's Q (χ2) and I 2 statistics, and publication bias was assessed with Egger's test. Twenty-four publications met inclusion criteria, including 1,887,074 adults, and were included in the systematic review. Ten publications that provided HRs were included in the meta-analysis for highest compared with lowest intakes, and an additional 7 publications that provided mortality or incident rate ratios or relative risks were included in supplemental meta-analyses. Of 108 reported HRs (or similar), 97 (79%) were either not statistically significant (n = 86) or indicated lower cancer risk (n = 11) associated with the highest intakes of bread. The meta-analysis indicated that bread intake was not associated with site-specific cancer risk [HR: 1.01; 95% confidence interval (CI): 0.89, 1.14; P = 0.92; 8 publications] or total cancer mortality (HR: 0.90; 95% CI: 0.73, 1.11; P = 0.32; 2 publications). Supplemental meta-analyses using all risk estimates in addition to HRs confirmed these findings. Whole-grain bread was associated with a lower site-specific cancer risk, mainly because of reduced colorectal cancer risk. Results of the systematic review and meta-analysis indicate that bread consumption is not associated with increased site-specific cancer risk, whereas high whole-grain/nonwhite bread consumption is associated with lower total cancer mortality and colorectal cancer risk. This study was registered at Clinical Trials Registry of PROSPERO as registration number CRD42023414156.

Dietary patterns and breast cancer risk, prognosis, and quality of life: A systematic review

Background

Statistics indicate that the morbidity of breast cancer is increasing globally, and its (overall figures) incidence has now surpassed that of lung cancer for the first time. The relation between a whole dietary pattern, rather than of a single food or nutrient, and breast cancer (BC) should be examined for findings to capture the complexities of diet and the potential for synergism between dietary components. Hence, the effects of dietary patterns on breast cancer have recently attracted increasing attention.

Objective

To systematically review the effects of dietary patterns on breast cancer risk, prognosis, and quality of life in survivors.

Methods

This systematic review was conducted following PRISMA guidelines and was registered in PROSPERO. Data from Ovid, China Biomedical Literature Database, Wanfang Data Knowledge Service Platform, CNKI, PubMed, Weipu, The Cochrane Library, Duxiu Data, ProQuest, Embase, Web of Science, and Scopus Database were retrieved and evaluated.

Results

A total of 47 studies that investigated the association between eating patterns and breast cancer were identified. Ten studies evaluated the effect of the model on treatment outcome and prognosis of breast cancer and two cross-sectional studies examined the influence of dietary patterns on quality of life. The resulting favorable dietary patterns were shown to regulate metabolic biomarkers, antioxidants, anti-inflammatory agents, and protective genes, and inhibit cell proliferation and invasion.

Conclusion

Numerous studies have examined the effects of healthy eating, plant-based, anti-inflammation, low-fat, and other favorable dietary patterns in relation to breast cancer. However, few studies reported significant associations and the studies had limitations, suggesting that the current findings should be interpreted with caution.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, CRD4202 2350171.

Milk Intake in Early Life and Later Cancer Risk: A Meta-Analysis

Dairy consumption in adulthood has been demonstrated to influence cancer risk. Although childhood and adolescence represent critical periods of rapid growth, the relationship between milk intake in early life and later cancer risk is unclear. Thus, we examined this relationship by conducting a meta-analysis of the observational studies. PubMed and Embase were searched for relevant articles that were published throughout December 2021. The summary relative risk (RR) and 95% confidence interval (CI) were estimated using the DerSimonian-Laird random-effects model. The summary RR for the highest vs. lowest milk intake was 0.83 (95% CI = 0.69–1.00; p = 0.05; I² = 60%; seven studies) for breast cancer, 0.98 (95% CI = 0.72–1.32; p = 0.88; I² = 51%; four studies) for prostate cancer, and 0.90 (95% CI = 0.42–1.93; p = 0.78; I² = 83%; three studies) for colorectal cancer. No evidence of an association emerged in subgroup analyses of menopausal status, cancer stage, fat content of milk, life stage of milk intake, or study design. Consistent results were observed in the meta-analyses using total dairy intake. In conclusion, milk intake during childhood and adolescence might not be associated with risks of breast, prostate, and colorectal cancer later in life. Given the small number of studies that were included in our meta-analysis, and the high heterogeneity, more studies are warranted for a definitive conclusion.

Clinical features and first degree relative breast cancer, their correlation with histological tumor grade: a 5-year retrospective case study of breast cancer in Mizoram, India

The aim was to assess the association of histological tumor grade with other clinical features and epidemiological factors of women with invasive breast carcinoma. A retrospective study of 103 Mizo breast cancer patients visiting hospitals was made in Aizawl, Mizoram, Northeast India. With a prior consent, information on epidemiological factors and family history in relation to cancer was obtained. Clinical reports were obtained from their medical records. The frequency of distribution was calculated for age at diagnosis and tumor characteristics. Statistical analysis for different variables was done using a chi-square test. p < 0.05 was considered significant. The histological tumor grades in our studies were found to be associated with lymph node invasion (p < 0.021), different subtype of hormone receptor such as ER status (p < 0.004), ER/PR status (p < 0.007), HER2/neu status (p < 0.014), and ER/PR/HER2 status (p < 0.025). A patient with a family history of breast cancer in their 1st degree relative is also seen to have association in determining the tumor grade (p < 0.003). Reproductive history, lifestyle and dietary habits, tobacco, and alcohol consumption were found to have no influence on breast cancer tumor grade. Our results showing significant correlation between status of lymph node, ER, PR, and HER2/neu oncoprotein and family history with 1st degree relative breast cancer are the first time report to target and focus on the possible role of biomarkers for diagnosis among the Mizo tribal breast cancer patients.

Pre- and post-diagnostic intake of whole grain and dairy products and breast cancer prognosis: the Danish Diet, Cancer and Health cohort

PURPOSE

Fiber rich foods and dairy products have been suggested to be associated with breast cancer prognosis, though existing research is limited and either report on pre- or post-diagnostic dietary intake in relation to breast cancer prognosis. We investigated the associations between intake of whole grain (WG) and dairy products assessed both pre- and post-diagnostically in relation to breast cancer prognosis.

METHODS

A total of 1965 women from the Diet, Cancer and Health cohort who were diagnosed with breast cancer between baseline (1993-1997) and December 2013 were included and followed for a median of 7 years after diagnosis. During follow-up, 309 women experienced breast cancer recurrence and 460 women died, of whom 301 died from breast cancer. Dietary assessment by food frequency questionnaires was obtained up to three times, pre- and post-diagnostic, over a period of 18 years. Cox proportional hazard models were used to estimate hazard ratios.

RESULTS

No associations were observed between pre- or post-diagnostic intake of total WG or total dairy products and breast cancer prognosis. A high pre-diagnostic intake of oatmeal/muesli was associated with lower all-cause mortality (HR 0.76, 95% CI 0.59-0.99), whereas high post-diagnostic intake of rye bread was associated with higher breast cancer-specific mortality (HR 1.29, 95% CI 1.02-1.63). A generally high intake of cheese was associated with a higher recurrence rate.

CONCLUSION

Pre-diagnostic intake of oatmeal/muesli was associated with lower all-cause mortality, and post-diagnostic intake of rye bread was associated with higher breast cancer specific mortality.

Overview of the Anticancer Profile of Avenanthramides from Oat

Cancer represents one of the leading causes of death worldwide. Progresses in treatment of cancer have continued at a rapid pace. However, undesirable side effects and drug resistance remain major challenges for therapeutic success. Natural products represent a valuable starting point to develop new anticancer strategies. Polyphenols, well-known as antioxidant, exert anticancer effects through the modulation of multiple pathways and mechanisms. Oat (Avena sativa L., Poaceae) is a unique source of avenanthramides (AVAs), a group of polyphenolic alkaloids, considered as its signature compounds. The present review aims to offer a comprehensive and critical perspective on the chemopreventive and chemotherapeutic potential of AVAs. AVAs prevent cancer mainly by blocking reactive species. Moreover, they exhibit potential therapeutic activity through the modulation of different pathways including the activation of apoptosis and senescence, the block of cell proliferation, and the inhibition of epithelial mesenchymal transition and metastatization. AVAs are promising chemopreventive and anticancer phytochemicals, which need further clinical trials and toxicological studies to define their efficacy in preventing and reducing the burden of cancer diseases.

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.

Vegetable-Fruit-Soybean Dietary Pattern and Breast Cancer: A Meta-Analysis of Observational Studies

Breast cancer is one of the most common cancers among women worldwide, and several studies have investigated the association of dietary patterns and breast cancer. However, findings of studies are inconclusive. Therefore, we aimed to conduct a meta-analysis to summarize the available data regarding the association of vegetable-fruit-soybean dietary pattern and breast cancer. A systematic literature search was conducted via PubMed, Web of Science and EMBASE to identify eligible cohort studies before February 2019. A total of 12 cohort studies were included in the meta-analysis. The summary relative risks (RR) with 95% CI were calculated with a fixed-effects model. The overall RR of breast cancer for the highest versus lowest intake of vegetable-fruit-soybean dietary pattern was 0.87 (95% CI, 0.82-0.91), with little heterogeneity (p=0.73, I2=0%). There was no obvious publication bias according to funnel plot and Begg's and Egger's test. In summary, the evidence from this meta-analysis indicates that vegetable-fruit-soybean dietary pattern was inversely associated with breast cancer. However, well-designed randomized controlled trials are needed to elicit the clear effect of vegetable-fruit-soybean dietary pattern and breast cancer. Women can reduce the risks of breast cancer by eating more fruits and vegetables and soybeans, which is a constructive suggestion.