Risk of ovarian carcinoma and consumption of vitamins A, C, and E and specific carotenoids - A prospective analysis

BACKGROUND. Antioxidant vitamins may decrease risk of cancer by limiting ox idative DNA damage leading to cancer initiation. Few prospective studies ha ve assessed relations between antioxidant vitamins arid ovarian carcinoma. METHODS. The authors prospectively assessed consumption Of Vitamins A, C, a nd E and specific carotenoids, as well as fruit and vegetable intake, in re lation to ovarian carcinoma risk among 80,326 participants in the Nurses' H ealth Study who had no history of cancer other than nonmelanoma skin carcin oma. Women reported on known and Suspected ovarian carcinoma risk factors i ncluding reproductive factors, smoking, and use of vitamin supplements on b iennial mailed questionnaires from 1976 to 1996. Food frequency questionnai res were included in 1980, 1984, 1986, and 1990. The authors confirmed 301 incident cases of invasive epithelial ovarian carcinoma during 16 years of dietary follow-up (1980-1996). Pooled logistic regression was used to contr ol for age, oral contraceptive use, body mass index, smoking history, parit y, and tubal ligation. RESULTS. The authors observed no association between ovarian carcinoma risk and antioxidant vitamin consumption from foods, or foods arid Supplements together. The multivariate relative risks (95% confidence intervals [CIs]) for ovarian carcinoma among women in the highest versus lowest quintile of intake were 1.04 (95% Cl, 0.72-1.51) for vitamin A from foods arid suppleme nts: 1.01 (95% Cl, 0.69-1.47) for vitamin Q 0.88 (95% Cl, 0.61-1.27) for vi tamin E; arid 1.10 (95% Cl, 0.76-1.59) for beta -carotene. Among users of v itamin supplements, the authors found no evidence of an association between dose or duration of any specific vitamin arid ovarian carcinoma risk, alth ough the authors had limited power to assess these relations. No specific f ruits or vegetables were associated significantly with ovarian carcinoma ri sk. The authors found no association between ovarian carcinoma arid consump tion of total fruits or vegetables, or specific Subgroups including crucife rous vegetables, green leafy vegetables, legumes, Or Citrus fruits. Women W ho consumed at least 2.5 total servings of fruits arid vegetables as adoles cents had a 46% reduction in ovarian carcinoma risk (relative risk, 0.54, 9 5% Cl, 0.29-1.03; P value for trend 0.04). CONCLUSIONS. These data do not support in important relation between consum ption of antioxidant vitamins from foods or supplements, Or intake of fruit s and vegetables, and incidence of ovarian carcinoma in this cohort. Howeve r, modest associations cannot be excluded, and the authors' finding of an i nverse association for total fruit and vegetable intake during adolescence raises tile possibility that the pertinent exposure period may be much earl ier than formerly anticipated. (C) 2001 American Cancer Society.