Associations between Preserved Foods and Breast Cancer Risk in Hong Kong Chinese Women.

Preserved food such as cured foods may contain nitrate and nitrite that may contribute to the breast cancer development. Evidence on the associations between these preserved food intakes and risk of breast cancer is sparse. This study aimed to examine the associations between preserved foods (i.e., cured meat, pickled vegetables, canned meat, and canned fruit/vegetables) and breast cancer risk in Hong Kong Chinese women. A total of 1,307 breast cancer cases and 1,050 age-matched controls were recruited from three hospitals during November 2011 through January 2018. We used a standardized questionnaire to collect information on dietary factors, including preserved foods. Unconditional multiple logistic regression was performed to calculate the adjusted odds ratio (AOR) of breast cancer in relation to preserved food with adjustment of potential confounders. We further performed stratified analysis according to the breast cancer biology subtypes. We found that cured meat consumption was significantly associated with the risk of breast cancer [AOR, 1.32; 95% confidence interval 95% (CI), 1.06-1.64]. Compared with no cured meat consumption, cured meat intake ≥ once per week was associated with an AOR of 2.66 (95% CI, 1.38-5.35). Women with canned fruit/vegetable ≥ consumption once per week had a higher risk of breast cancer (OR, 1.19; 95% CI, 1.00-1.41), particularly for the HER2-positive subtypes, but it became borderline after adjustment of confounders. Our study reveals a positive association between consumption of cured meat and breast cancer risk in Chinese population. Cured meat intake might be a potential novel risk factor for breast cancer but this would have to be confirmed by large prospective cohort studies. PREVENTION RELEVANCE: The main finding of this case-control study, an association between cured meat intake and a higher risk of breast cancer in Hong Kong Chinese women, contributes to the growing evidence for population-level health benefits of reducing cured meat consumption.