Positive Health Online

Abstract

WANG and COLLEAGUES,  Department of Epidemiology and Population Health, School of Public Health and Information Sciences, University of Louisville, 555 South Floyd Street, Louisville, KY 40202, USA studied the associations between dietary intake of antioxidant vitamins from fruits and vegetables with breast cancer risk and oestrogen receptor status in non-Hispanic White and Hispanic women living in the Southwestern US.

Background

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. The authors assessed the associations of the dietary intake of antioxidant vitamins commonly found in fruits and vegetables with breast cancer risk and oestrogen receptor (ER) status among NHW and Hispanic women living in the Southwestern US.

Methodology

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 oestrogen 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.

References

Wang C, Baumgartner RN, Yang D, Slattery ML, Murtaugh MA, Byers T, Hines LM, Giuliano AR and Baumgartner KB. No evidence of association between breast cancer risk and dietary carotenoids, retinols, vitamin C and tocopherols in Southwestern Hispanic and non-Hispanic White women. Breast Cancer Research & Treatment. 114 (1): 137-45. Mar 2009.

Comment

The above two studies both used dietary intake questionnaires to study the relationship between nutrients in fruits and vegetables and either endometrial cancer (EC) or breast cancer. However the results and conclusions obtained from these studies couldn't have been different, with the first study finding significant associations between vegetables and nutrients and EC, whereas the second study found no association at all. The methodologies used to conduct the questionnaires and the statistical appeared to vary, with the first study doing more rigorous statistical analyses.