Mediterranean dietary pattern is associated with lower incidence of premenopausal breast cancer in the Seguimiento Universidad de Navarra (SUN) Project

Effects of diets on risks of cancer and the mediating role of metabolites

Research on the association between dietary adherence and cancer risk is limited, particularly concerning overall cancer risk and its underlying mechanisms. Using the UK Biobank data, we prospectively investigate the associations between adherence to a Mediterranean diet (MedDiet) or a Mediterranean-Dietary Approaches to Stop Hypertension Diet Intervention for Neurodegenerative Delay diet (MINDDiet) and the risk of overall and 22 specific cancers, as well as the mediating effects of metabolites. Here we show significant negative associations of MedDiet and MINDDiet adherence with overall cancer risk. These associations remain robust across 14 and 13 specific cancers, respectively. Then, a sequential analysis, incorporating Cox regression, elastic net and gradient boost models, identify 10 metabolites associated with overall cancer risk. Mediation results indicate that these metabolites play a crucial role in the association between adherence to a MedDiet or a MINDDiet and cancer risk, independently and cumulatively. These findings deepen our understanding of the intricate connections between diet, metabolites, and cancer development.

A Clustering Study of Sociodemographic Data, Dietary Patterns, and Gut Microbiota in Healthy and Breast Cancer Women Participating in the MICROMA Study

SCOPE

This work is part of the clinical study NCT03885648 registered in ClinicalTrials.gov, aimed at studying the relationship among breast cancer, microbiota, and exposure to environmental pollutants. As a first step, we characterized and evaluated risk factors of the participants.

METHODS AND RESULTS

A case-control study was designed with breast cancer (cases, n = 122) and healthy women (controls, n = 56) recruited in two hospitals of Andalusia (Southern Spain). Participants answered questionnaires of Mediterranean diet adherence and food frequency. Data were collected from medical histories and microbiota was analyzed on stool samples. Most cases (78.2%) were diagnosed as stages I and II. Cases had higher age, body mass index (BMI), glucose, cholesterol, and potassium values than controls. Cases exhibited higher adherence to the Mediterranean diet and their food consumption was closer to that dietary pattern. A hierarchical cluster analysis revealed that the Bacillota/Bacteroidota ratio was the most relevant variable in women with breast cancer, which was higher in this group compared with controls.

CONCLUSION

Although cases exhibited higher adherence to the Mediterranean diet compared with controls, they presented features and microbiota alterations typical of the metabolic syndrome, probably due to their higher BMI and reflecting changes in their lifestyle around the time of diagnosis.

The Impact of Modern Dietary Practices on Cancer Risk and Progression: A Systematic Review

Cancer is a leading cause of mortality around the world, despite continued advancements in the management of cancer. Recent research efforts have shifted to evaluating the role that modifiable risk factors play in cancer risk and development, as diet and nutrition have been found to play a significant role in the onset and progression of cancer. As a result, there has been an increasing focus on the impact of dietary modifications on preventing the onset, progression, and reoccurrence of cancer. In this systematic review, data were collected on three common diets, the Mediterranean diet (MD), ketogenic diet (KD), and plant-based diet, to gain insight into the application of these three dietary modification approaches for risk prevention and limitation of cancer burden. Initially, 4,397 articles were identified from three databases (Ovid, Web of Science, and CINHAL). After removing studies based on the exclusion criteria, only 23 studies were eligible to be included in the systematic review of which 15 evaluated the MD, four assessed the ketogenic diet, and four evaluated the plant-based diet. Each article was considered for its methods, procedures, and findings. The findings indicate that dietary interventions may effectively reduce the odds of cancer development and the advancement of diagnosed cancers. With the introduction of the MD, KD, and plant-based diets, significant improvements in lowering cancer development, recurrence-free status, and limiting tumor growth were noted across numerous cancer types. Currently, the MD has been extensively studied in the literature, and amongst the widest variety of cancer types. Additional information and evaluation are required on the ketogenic and plant-based diets to fully understand their impact on the cancer burden across a wider subset of cancers. Clinicians should evaluate and recommend nutritional adaptations to their patients to limit the development of specific cancers and as an adjunctive therapy to traditional pharmacological treatment options for patients with diagnosed cancers.

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.

Exploratory dietary patterns and cognitive function in the "Seguimiento Universidad de Navarra" (SUN) Prospective Cohort

BACKGROUND

Dementia is projected to affect 135 million by 2050. Diet is a pertinent target for primary prevention, but firm recommendations for dementia prevention are not available yet. Our aim was to address the association between exploratory (empirically derived) dietary patterns (DP) and changes in the Spanish Telephone Interview for Cognitive Status (STICS-m, maximum score = 41 points) over 6 years.

METHOD

Information on diet was collected with a validated 136-item food-frequency questionnaire from 803 participants in the Mediterranean cohort "Seguimiento Universidad de Navarra." We used principal component analysis to derive exploratory DP. The derived DP were associated with change in STICS-m scores over 6 years, through adjusted multiple linear regression models.

RESULTS

Two main DP were identified. The first DP resembled a Western dietary pattern (WDP)-high in sugar, fat, processed foods, and red meat-and the second DP resembled a Mediterranean dietary pattern (MDP)-high in vegetables, fruits, nuts, fish, and olive oil. Adherence to the WDP (tertile 3 vs tertile 1) was significantly associated with negative STICS-m changes after 6 years (between-tertile difference in changes: -0.80 points; 95% confidence interval [CI] -1.51, -0.08, p value = 0.03). Meanwhile, the MDP showed a positive +0.71 point (95% CI 0.15, 1.26, p value = 0.01) between-tertile difference in changes in the STICS-m score.

CONCLUSIONS

A healthy, prudent, MDP was associated with less decline in cognitive function and, thus, could help to lower dementia incidence. Western-type diets were associated with a greater decline in cognitive performance and could increase dementia incidence.

An updated systematic review and meta-analysis on adherence to mediterranean diet and risk of cancer

Purpose

The aim of current systematic review was to update the body of evidence on associations between adherence to the Mediterranean diet (MedDiet) and risk of cancer mortality, site-specific cancer in the general population; all-cause, and cancer mortality as well as cancer reoccurrence among cancer survivors.

Methods

A literature search for randomized controlled trials (RCTs), case–control and cohort studies published up to April 2020 was performed using PubMed and Scopus. Study-specific risk estimates for the highest versus lowest adherence to the MedDiet category were pooled using random-effects meta-analyses. Certainty of evidence from cohort studies and RCTs was evaluated using the NutriGrade scoring system.

Results

The updated search revealed 44 studies not identified in the previous review. Altogether, 117 studies including 3,202,496 participants were enclosed for meta-analysis. The highest adherence to MedDiet was inversely associated with cancer mortality (RR_cohort: 0.87, 95% CI 0.82, 0.92; N = 18 studies), all-cause mortality among cancer survivors (RR_cohort: 0.75, 95% CI 0.66, 0.86; N = 8), breast (RR_{observational}: 0.94, 95% CI 0.90, 0.97; N = 23), colorectal (RR_{observational}: 0.83, 95% CI 0.76, 0.90; N = 17), head and neck (RR_{observational}: 0.56, 95% CI 0.44, 0.72; N = 9), respiratory (RR_cohort: 0.84, 95% CI 0.76, 0.94; N = 5), gastric (RR_{observational}: 0.70, 95% CI 0.61, 0.80; N = 7), bladder (RR_{observational}: 0.87, 95% CI 0.76, 0.98; N = 4), and liver cancer (RR_{observational}: 0.64, 95% CI 0.54, 0.75; N = 4). Adhering to MedDiet did not modify risk of blood, esophageal, pancreatic and prostate cancer risk.

Conclusion

In conclusion, our results suggest that highest adherence to the MedDiet was related to lower risk of cancer mortality in the general population, and all-cause mortality among cancer survivors as well as colorectal, head and neck, respiratory, gastric, liver and bladder cancer risks. Moderate certainty of evidence from cohort studies suggest an inverse association for cancer mortality and colorectal cancer, but most of the comparisons were rated as low or very low certainty of evidence.

Electronic supplementary material

The online version of this article (10.1007/s00394-020-02346-6) contains supplementary material, which is available to authorized users.