Premenopausal Breast Cancer Risk and Intake of Vegetables, Fruits, and Related Nutrients

• Published in: JNCI : Journal of the National Cancer Institute 1996-03, Vol.88 (6), p.340-348
• Main Authors: Freudenheim, Jo L., Marshall, James R., Vena, John E., Laughlin, Rosemary, Brasure, John R., Swanson, Mya K., Nemoto, Takuma, Graham, Saxon
• Format: Article
• Language: English
• Subjects: Adult; Ascorbic Acid; Biological and medical sciences; Breast cancer; Breast Neoplasms - epidemiology; Breast Neoplasms - etiology; Carotenoids; Case-Control Studies; Diet; Dietary Fiber; Evaluation Studies as Topic; Folic Acid; Fruit; Fruits; Gynecology. Andrology. Obstetrics; Health risk assessment; Humans; Male; Mammary gland diseases; Medical sciences; Middle Aged; Nutrition; Premenopause - physiology; Risk Factors; Tumors; Vegetables; Vitamin E
• ISSN: 0027-8874; 1460-2105
• DOI: 10.1093/jnci/88.6.340

Background: Given the international variations in breast cancer incidence rates and the changes in breast cancer incidence among migrant populations, it has been hypothesized that diet is a factor influencing risk of this disease. Many studies indicate that a diet high in vegetables and fruits may protect against breast cancer. Purpose: We conducted a case—control study of diet, including the intake of non-food supplements, and premenopausal breast cancer risk. We evaluated in detail usual intake of vegetables and fruits (each measured as the total reported grams consumed for all queried vegetables and fruit), vitamins C and E, folic acid, individual carotenoids, and dietary fiber with its components. Methods: Case patients (n = 297) were identified through pathology records from hospitals in Erie and Niagara counties in western New York. They consisted of premenopausal women 40 years of age or older who were diagnosed with breast cancer from November 1986 through April 1991. Control subjects (n = 311), frequency-matched to case patients on the basis of age and county of residence, were randomly selected from New York State Department of Motor Vehicles records. In-person interviews included detailed reports of usual diet in the period 2 years before the interview. Unconditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Results: There was a reduction in risk associated with high intake of several nutrients. With the lowest quartile of intake as the referent, adjusted ORs for the highest quartile of intake for specific nutrients were as follows: vitamin C (OR = 0.53; 95% CI = 0.33–0.86), αtocopherol (OR = 0.55; 95% CI = 0.34–0.88), folic acid (OR = 0.50; 95% CI = 0.31–0.82), α-carotene (OR = 0.67; 95% CI = 0.42–1.08) and β-carotene (OR = 0.46; 95% CI = 0.28–0.74), Iutein + zeaxanthin (OR = 0.47; 95% CI = 0.28–0.77), and dietary fiber from vegetables and fruits (OR = 0.48; 95% CI = 0.30–0.78). No association with risk was found for β-cryptoxanthin, lycopene, or grain fiber. Fruits were weakly associated with a reduction in risk (fourth quartile OR = 0.67; 95% CI = 0.42–1.09). No association was found between breast cancer risk and intake of vitamins C and E and folic acid taken as supplements. A strong inverse association between total vegetable intake and risk was observed (fourth quartile OR = 0.46; 95% CI = 0.28–0.74). This inverse association was found to be independent of vitamin C, α-tocopherol, folic