The Western vs. Mediterranean Diet: is there an association between dietary patterns and reduction in breast cancer risk?

By Bhavana KunkalikarApr 27 2023Reviewed by Lily Ramsey, LLM

In a recent study published in the Nutrients journal, researchers compared the impacts of Western and Mediterranean diets on breast cancer risk.

Study: The Risk of Breast Cancer between Western and Mediterranean Dietary Patterns. Image Credit: sabrinimada/Shutterstock.com

Background

Breast cancer is a significant global health concern, as it is the most prevalent form of cancer, the primary cause of cancer mortality among women, and has the highest number of reported cases of all cancers.

Studies are still identifying specific variables that contribute to developing breast cancer and new therapies and prevention techniques. Various demographic, genetic, reproductive, environmental, and lifestyle factors are associated with breast cancer.

About the study

In the present study, researchers summarized the active compounds of Western and Mediterranean diets believed to be vital in breast cancer prevention.

To ensure the validity of this review, the team performed a systematic literature search in PubMed using the terms "breast cancer" and "diet pattern" to identify the most prevalent dietary trends across the globe. The inclusion criteria for this review included studies in the English language and peer-reviewed articles published after 2017.

A secondary search used "breast cancer" and particular constituents in the identified diet trends to investigate the association between breast cancer risk and particular dietary elements.

The inclusion criteria for the secondary search were restricted to English-language peer-reviewed articles but were not time-bound.

Results

The Western diet involves a high intake of unhealthy lipids, including abundant saturated and trans fats, omega-6 polyunsaturated fatty acids (PUFA), and omega-3 PUFA deficiency.

An unbalanced omega-6/omega-3 ratio of 20:1 is of particular concern because it is known to induce metabolic complications, particularly inflammatory processes.

A high-fat diet has been shown to cause chronic inflammation, obesity, dysbiosis of the intestinal microbiota, and cancer. Another study found that the adjusted odds ratio for breast cancer in women who consume more than seven servings of whole grains per week was 0.49.

The European Prospective Investigation into Cancer and Nutrition (EPIC) conducted a study to determine the association between trans fat intake and breast cancer risk. In the multivariable-adjusted model, the results indicated that higher ingestion of industrial trans fats was associated with an elevated risk of breast cancer.

Altogether, the Western dietary regimen may be abundant in calories and poor in nutrients, facilitating the higher consumption of calories than the body requires, resulting in weight gain and a higher risk of obesity. Being obese or overweight is a recognized breast cancer risk factor.

The incidence of breast cancer has decreased due to the Mediterranean diet's protective effect against the development of the disease.

A recent case-control study suggests that premenopausal and postmenopausal women with a diet rich in vegetables, fruits, fish, and olive oil may have a reduced risk of developing breast cancer.

This positive outcome is attributed to the regular intake of flavonoids, fiber, and antioxidants derived from food, which are believed to decrease estrogen levels, increase sex hormone proportions, neutralize free radicals, safeguard deoxyribonucleic acid (DNA) from damage, and reduce oxidative stress.

Phytochemicals in plant-based diets have demonstrated health benefits, including reduced breast cancer risk. Several epidemiological studies indicate that eating vegetables and fruits, specifically cruciferous vegetables, can lower the risk of several types of cancer, such as breast cancer. According to studies, fucoxanthin has anti-inflammatory properties in cancer prevention and therapy.

According to a study, Western dietary trends were associated with an increased risk of invasive lobular (ILC) and ductal carcinomas (IDC). In addition, the Western diet was associated with an elevated ILC and IDC risk.

In contrast, the Mediterranean diet was linked to a decreased incidence of IDC and ILC. Moreover, a study found a significant positive association between human epidermal growth factor receptor 2 (HER2)+ and estrogen/progesterone (ER/PR)+ breast cancer and Western dietary trends.

A significant difference did not distinguish other dietary trends and breast cancer subtypes.

Conclusion

The study findings showed that bioactive compounds found in fruits, whole grains, legumes, and vegetables regulate several bodily functions and, in some instances, may work in tandem with the gut microbiome to yield health benefits.

A dietary trend incorporating these nutrient-dense foods, such as the Mediterranean diet, is ideal for optimal health, although no single food can treat or prevent disorder.

Yet, a balanced lifestyle and diet, which includes regular physical activity and moderate alcohol consumption, are also essential for maintaining health.