Onion and Garlic Intake and Breast Cancer, a Case-Control Study in Puerto Rico

Abstract

Studies show an inverse association between onion and garlic intake and risk of cancers of the lung, prostate, and stomach. There is limited evidence on the association between onion and garlic intake and breast cancer. We assessed this association in a population-based, case-control study in Puerto Rico. Incident, primary breast cancer cases (n = 314) were identified among women aged 30–79 from hospital and clinic records. Controls (n = 346) were women with no history of cancer other than nonmelanoma skin cancer, residents of the same area. Dietary intake was estimated using a food frequency questionnaire. Total onion and garlic intake included sofrito (a popular garlic- and onion-based condiment) intake frequency. Unconditional logistic regression assessed the association between onion and garlic consumption and breast cancer adjusting for age, education, parity, family history, body mass index, age at menarche, total energy, and smoking. Inverse associations with breast cancer were observed for moderate (OR (odds ratio) = 0.59, 95% CI (confidence interval): 0.35, 1.01) and high consumption (OR = 0.51, 95% CI: 0.30, 0.87) compared to low consumption of onion and garlic (P_trend = 0.02). Results were similar when stratified by menopausal status. Study results suggest that high onion and garlic consumption is protective against breast cancer in this population.

Acknowledgments

The views, opinions, or endorsements are solely the responsibility of the authors and do not necessarily reflect the official views of supporting agencies. We thank the field personnel and all the participants in the Atabey Study.

Author Contributions

Ms. Desai analyzed the data and wrote the manuscript. Drs. Schelske-Santos, Mansilla-Rivera, Ramírez-Marrero designed the questionnaire used in the study, reviewed and edited the manuscript. Dr. Rosario-Rosado developed the methodology for the case ascertainment and the sample selection of the controls, reviewed and edited the manuscript. Dr. Nazario acquired funding, designed the study, designed the questionnaire used in the study, developed the methodology for the case ascertainment and the sample selection of the controls, supervised data collection, reviewed and edited the manuscript. Dr. Freudenheim acquired funding, designed the study, designed the questionnaire used in the study, supervised data collection, reviewed and edited the manuscript. Dr. Nie cleaned the data and calculated variables including the nutrient intakes from the questionnaire, reviewed and edited the manuscript. Drs. Myneni and Zhang contributed to data analysis, reviewed and edited the manuscript. Dr. Mu supervised and contributed to data analysis, reviewed and edited the manuscript. All authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.

Disclosure Statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The Epidemiology of Breast Cancer in Puerto Rico Study (Atabey) was supported by the Congressionally Directed Medical Research Programs (CDMRP) Grant W81XWH-07-1-0329 BCRP HBCU/MI Partnership Training Award, and in part by the Consortium of Clinical and Translational Research of Puerto Rico under the award number 2U54MD007587 from the National Institute on Minority Health and Health Disparities of the National Institutes of Health.