Role of a Whole Plant Foods Diet in Breast Cancer Prevention and Survival

J Am Nutr Assoc. 2025 Jan 9:1-17. doi: 10.1080/27697061.2024.2442631. Online ahead of print.

Abstract

Breast cancer (BC) is one of the leading causes of death and morbidity among women worldwide. Epidemiologic evidence shows that the risk of BC and other chronic diseases decreases as the proportion of whole plant foods increases, while the proportion of animal foods (fish, meat, poultry, eggs, seafood, and dairy products) and non-whole plant foods (e.g., refined grains, added sugars, French fries) in the diet decreases. Whole plant foods include fruits, vegetables, roots, tubers, whole grains, legumes, nuts, and seeds from which no edible part has been removed and to which no non-whole food been added. A whole plant foods diet lowers insulin resistance, inflammation, excess body fat, cholesterol, and insulin-like growth factor 1 and sex hormone bioavailability; it also increases estrogen excretion, induces favorable changes in the gut microbiota, and may also favorably affect mammary microbiota composition and decrease the risk of early menarche, all contributing to reduced BC incidence, recurrence, and mortality. This review explores the connection between a whole plant foods diet and BC risk and mortality as well as the potential mechanisms involved. Additionally, this diet is compared with other dietary approaches recommended for BC. A whole plant foods diet seems the optimal dietary pattern for BC and overall disease prevention as it exclusively consists of whole plant foods which, based on existing evidence, lead to the best health outcomes.

Keywords: Plant‑based diet; breast cancer; breast cancer and diet; breast cancer and plant‑based diet; breast cancer survival; vegan diet; whole foods plant‑based diet.

Plain language summary

Epidemiologic evidence shows that the risk of breast cancer decreases as the proportion of whole plant foods in the diet increases at the expense of animal foods and non–whole plant foods.Compared with animal and non–whole plant foods, whole plant foods reduce insulin resistance, inflammation, cholesterol, and the bioavailability of insulin-like growth factor 1 and sex hormones; they induce favorable changes in gut microbiota composition and metabolites, increase fecal estrogen excretion, and may increase bile salt metabolites in the mammary gland and prevent early menarche, all contributing to lower breast cancer risk.Consumption of whole plant foods instead of animal and non–whole plant foods is consistently associated with lower risk of chronic diseases and mortality.A whole plant foods diet seems more advantageous than animal food–containing diets (e.g., Mediterranean) for breast cancer and overall disease prevention given that it is composed entirely of whole plant foods which, according to existing evidence, leads to the best health outcomes.

Publication types

  • Review