Dietary Patterns and Breast Cancer Risk

Breast cancer remains the most commonly diagnosed malignancy in women worldwide and dietary habits have emerged as key modifiable factors capable of influencing its incidence and prognosis. Rather than focusing solely on individual nutrients, research has shifted towards examining overall dietary patterns, which capture the complex interactions among nutrients, bioactive compounds and lifestyle factors. Two paradigmatic patterns have dominated the field: the Western diet—characterised by high intakes of red and processed meat, refined grains, sugar‐sweetened beverages and saturated fat—and diets rich in plant‐based foods, such as the Mediterranean diet, which emphasises fruit, vegetables, whole grains, legumes, fish and healthy fats. Observational studies and controlled trials suggest that healthy dietary regimes may modulate hormone levels, inflammation, oxidative stress and gut microbiota composition, all of which play roles in breast tumour initiation and progression. Conversely, diets high in processed foods and refined carbohydrates may exacerbate pro‐inflammatory pathways and insulin resistance, thereby increasing cancer risk. The heterogeneity of findings across populations underlines the importance of considering cultural, genetic and environmental contexts. Globally, dietary modification offers a pragmatic approach to cancer prevention, with potential to integrate seamlessly into public health strategies and clinical guidance for reducing breast cancer burden.

Research from Nature Portfolio

Recent studies have applied comprehensive diet indices to assess associations with breast cancer risk. One large case–control investigation quantified adherence to overall, healthful and unhealthful plant-based diet indices in middle-aged women. It found that higher scores for overall and healthful plant-based diets were linked to substantially lower odds of breast cancer, whereas greater adherence to a less healthy plant-based pattern was associated with increased risk. These findings reinforce the importance of diet quality and the distinction between nutrient-dense plant foods and refined plant-derived products in modulating carcinogenic pathways.

Dietary Patterns and Breast Cancer Risk publication trend

The graph below shows the total number of articles in dietary patterns and breast cancer risk across all publications each year (not limited to Nature Index journals).

Technical terms

Dietary pattern: The overall combination and quantity of foods and beverages habitually consumed, reflecting synergistic nutrient interactions.

Plant-based diet index (PDI): A scoring system assigning positive values to plant foods and reverse values to animal foods, with variations to distinguish healthful from less healthful plant-derived items.

Odds ratio (OR): A measure in case–control studies expressing the likelihood of an outcome (such as disease) occurring in an exposed group compared to a reference group.

Meta-analysis: A statistical technique that combines the results of multiple independent studies to estimate an overall effect size.

References

1. Dietary patterns and breast cancer risk, prognosis, and quality of life: A systematic review. Frontiers in Nutrition (2023).
2. The Risk of Breast Cancer between Western and Mediterranean Dietary Patterns. Nutrients (2023).
3. Evidence Update on the Relationship between Diet and the Most Common Cancers from the European Prospective Investigation into Cancer and Nutrition (EPIC) Study: A Systematic Review. Nutrients (2021).
4. The association between plant-based dietary patterns and risk of breast cancer: a case–control study. Scientific Reports (2021).