A new study led by researchers at Rutgers Cancer Institute has found that Black women with breast cancer who consumed higher amounts of ultra-processed foods before their diagnosis faced a significantly increased risk of death. The research, published in eClinicalMedicine, is the first to establish this link specifically among Black women.
The study followed 1,733 Black women diagnosed with breast cancer in New Jersey between 2005 and 2019 as part of the Women's Circle of Health Follow-Up Study. Participants provided detailed accounts of their diets during home interviews conducted about ten months after diagnosis. Researchers tracked their health outcomes for a median period of 9.3 years.
Women in the highest tier of ultra-processed food consumption—averaging more than eight servings per day—were found to be 36% more likely to die from any cause and had a 40% higher likelihood of dying from breast cancer compared to those who ate less than three servings daily.
Ultra-processed foods are defined as industrially produced items containing additives and ingredients not typically used in home cooking. This category includes most sodas, deli meats, sweets, salty snacks, and pre-prepared fast foods. These products now make up an estimated 40-60% of calories in the American diet.
"Black women have the highest mortality rate from breast cancer compared with other racial or ethnic groups in the U.S.," said Tengteng Wang, lead author and member of the Cancer Prevention and Control Program at Rutgers Cancer Institute. "That's why we wanted to see what factors might contribute to these differences."
The findings mirror results from previous studies such as an analysis based on the UK Biobank data, which indicated a higher risk of cancer-related death among high consumers of ultra-processed foods across all cancer types in predominantly white populations.
"The average consumption is very similar to the U.K. population and also other U.S.-based studies like the Nurses' Health Study," Wang said. "I'd like to see more studies conducted among cancer survivors to confirm this, but the current evidence looks biologically reasonable now, particularly considering we have some ideas about the underlying biological mechanisms."
Researchers noted that one possible reason for this association is that ultra-processed foods can promote overeating and weight gain—a known risk factor for poorer outcomes after a cancer diagnosis. Adjusting for total calorie intake weakened but did not eliminate the association between processed food consumption and mortality rates.
Further analyses are underway examining whether inflammation or insulin resistance may play roles in these outcomes. The team will also look at tumor tissue samples and blood markers related to inflammation.
Processed meats were identified as especially problematic within ultra-processed food categories regarding increased risk for breast cancer deaths—a finding consistent with earlier research linking processed meat intake with higher cancer risks.
"Maybe it's too complicated for breast cancer patients to think about how to reduce consumption of ultra-processed foods in general," Wang said. "But we find processed meat is the top worst contributor among all UPF subgroups. So maybe a more detailed takeaway is to avoid this one thing."
Ultra-processed foods have come under growing scrutiny by public health experts following multiple reviews linking them with adverse health effects such as heart disease, diabetes, depression, and early death.
"Going back to cooking traditional meals can potentially save money and is generally better for your health," said Elisa Bandera, professor at Rutgers Robert Wood Johnson Medical School and co-leader of Rutgers Cancer Institute's Cancer Prevention and Control Research Program.
