No evidence of association between breast cancer risk and dietary carotenoids, retinols, vitamin C and tocopherols in Southwestern Hispanic and non-Hispanic White women.

OBJECTIVES: The effects of dietary intake of antioxidant vitamins on breast cancer risk are inconclusive. Moreover, little is known as to whether associations differ between non-Hispanic White (NHW) and Hispanic women. We assessed the associations of the dietary intake of antioxidant vitamins commonly found in fruits and vegetables with breast cancer risk and estrogen receptor (ER) status among NHW and Hispanic women living in the Southwestern U.S.
MATERIALS AND METHODS: Primary breast cancer cases in the 4-Corners region (Arizona, Colorado, New Mexico, Utah), diagnosed between October 1999 and May 2004, were identified through state cancer registries. Controls were frequency matched by ethnicity and age (+/-5 years). Information on demographic characteristics and other breast cancer risk factors prior to the referent year were collected by interviewer-administered computerized questionnaire. A modified extensive diet history questionnaire was used to assess dietary intake.
RESULTS: We did not find a protective effect of dietary antioxidants, such as alpha or beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, lycopene, retinol, vitamin C, alpha, delta, beta or gamma-tocopherol, on breast cancer risk in populations living in the Southwest. We did not find any consistent associations with multivariate risk of breast cancer or estrogen receptor status. Cigarette smoking was not a significant effect modifier of these associations.
CONCLUSION: This case-control study did not find any meaningful association of the dietary intake of antioxidant vitamins with breast cancer risk or ER status.