Positive Health Online

Abstract

SLATTERY and colleagues, University of Utah Medical School, Salt Lake City USA mslatter@dfm.utah.edu write that carotenoids have numerous biological properties which may underpin a role of them as chemopreventive agents ; however, apart from beta-carotene, little is known regarding how dietary carotenoids are associated with cancers, including colon cancer . The authors evaluated the associations between dietary alpha-carotene, beta-carotene, lycopene, lutein, zeaxanthin and beta-cryptoxanthin and risk of colon cancer.

Background

Methodology

Data were collected from 1993 case subjects with first primary incident adenocarcinoma of the colon and from 2410 control subjects. Dietary data were collected from a detailed diet-history questionnaire; nutrient values for dietary carotenoids were obtained from the USDA Coordinating Center carotenoid database 1998.

Results

Lutein was inversely associated with colon cancer in both men and women (odds ratio (OR) for upper quintile relative to lowest quintile of intake: 0.83. The greatest inverse association was observed among patients in whom colon cancer was diagnosed when they were young (OR: 0.66), and in those with tumours located in the proximal segment of the colon (OR: 0.65). Associations with other carotenoids were unremarkable.

Conclusion

The major dietary sources of lutein in patients with colon cancer and in control subjects were spinach, broccoli, lettuce, tomatoes, oranges and orange juice, carrots, celery and greens . These data suggest that incorporating these foods into the diet may help reduce risk of colon cancer.

References

Slattery ML et al. Carotenoids and colon cancer. The American Journal of Clinical Nutrition 71(2): 575-82. Feb 2000.