A new study of over 300,000 female participants found that diets high in meat, dairy, and processed sugar increased one’s relative risk of breast cancer by as much as 12 percent. The joint research conducted by the Catalan Institute of Oncology, the World Health Organization, and the Imperial College in London concluded that the inflammatory properties of these foods caused this spike in cancer risk. 

Food, inflammation, and disease

Chronic inflammation is the precursor to many serious diseases including diabetes, heart disease, and cancer. Certain foods—including meat, dairy, and processed sugars—have been shown to increase inflammation in the body. When certain foods are eaten regularly, the temporary (acute) inflammation induced by these foods can become chronic, creating a prime environment for the development of cancer. 

Researchers collected food frequency surveys from the 318,686 women participants for a year. The inflammatory nature of each diet was determined by the frequency of certain foods. Diets high in meat, butter, margarine, frying oils, and processed sugar were marked as inflammatory. Researchers found that participants who consumed the most inflammatory foods increased their relative risk of breast cancer by upwards of 12 percent. 

Lifestyle over nutrients

In lieu of concentrating on a specific nutrient—such as saturated fat—as previous research has done, this study looked at dietary patterns. The goal was not to create fear around individual nutrients but steer the conversation toward habit change. 

“People consume food not nutrients, thus examining overall dietary patterns—rather than single components of diets—can lead to more accurate conclusions when analyzing associations with a health outcome such as breast cancer,” Carlotta Castro-Espin of the Catalan Institute of Oncology and the author of the study explained. 

Plant-based diets have been linked to decreasing cancer risk as well as lowering levels of inflammation. Researchers point to the high antioxidant content of fruits and vegetables to explain the anti-inflammatory properties of whole, plant-based foods. Compared to the Standard American Diet (SAD) heavy in animal products, a whole, plant-based diet contains 64 times the amount of inflammation-fighting antioxidants.