Fast food

Avoid

2 studies · 1 recommendation

Last updated: February 25, 2026

Avoid2 studies

Frequent fast food consumption linked to significantly higher breast cancer risk

Two studies involving over 14,000 women associate fast food consumption with increased breast cancer risk. A case-control study of 3,148 African American and European American women found frequent fast food intake doubled breast cancer risk in postmenopausal European American women (OR = 2.35; 95% CI: 1.38–4.00) and premenopausal African American women (OR = 1.97; 95% CI: 1.13–3.43), with associations extending to estrogen receptor-positive tumors. A prospective cohort of 10,930 Spanish women demonstrated that adherence to cancer prevention guidelines—including fast food limitation—reduced postmenopausal breast cancer risk by 73% (HR = 0.27; 95% CI: 0.08–0.93). The elevated risk persists across racial groups, menopausal status, and tumor subtypes, supporting fast food avoidance as a modifiable dietary factor in breast cancer prevention.

Evidence

Adherence to the 2018 World Cancer Research Fund/American Institute for Cancer Research Recommendations and Breast Cancer in the SUN Project

Authors: Barrios Rodríguez, Rocío, Jiménez Moleón, José Juan

Published: July 13, 2020

In a prospective cohort of 10,930 Spanish female university graduates (SUN Project), an 8-item WCRF/AICR compliance score included limiting fast food consumption. Women achieving >5 points overall compliance versus ≤3 points had a multivariable-adjusted hazard ratio of 0.27 (95% CI: 0.08-0.93) for post-menopausal breast cancer. The significant inverse association was driven by the combined effects of all dietary and lifestyle components including fast food limitation.

View Source →

Nutr Cancer

In a case-control study with 1,692 African American and 1,456 European American women, frequent fast food consumption was associated with breast cancer risk in postmenopausal European American women (OR = 2.35; 95% CI: 1.38–4.00) and in premenopausal African American women (OR = 1.97; 95% CI: 1.13–3.43). Fast food intake was also linked to ER+ tumors in European American women (OR = 1.84; 95% CI: 1.22–2.77) and ER+ tumors in African American women. These associations persisted across menopausal and estrogen receptor status strata.

View Source →