Intakes of vitamins A, C, and E and use of multiple vitamin supplements and risk of colon cancer: a pooled analysis of prospective cohort studies
To evaluate the associations between intakes of vitamins A, C, and E and risk of colon cancer.
Using the primary data from 13 cohort studies, we estimated study- and sex-specific relative risks (RR) with Cox proportional hazards models and subsequently pooled RRs using a random effects model.
Among 676,141 men and women, 5,454 colon cancer cases were identified (7–20 years of follow-up across studies). Vitamin A, C, and E intakes from food only were not associated with colon cancer risk. For intakes from food and supplements (total), the pooled multivariate RRs (95% CI) were 0.88 (0.76–1.02, >4,000 vs. ≤1,000 μg/day) for vitamin A, 0.81 (0.71–0.92, >600 vs. ≤100 mg/day) for vitamin C, and 0.78 (0.66–0.92, >200 vs. ≤6 mg/day) for vitamin E. Adjustment for total folate intake attenuated these associations, but the inverse associations with vitamins C and E remained significant. Multivitamin use was significantly inversely associated with colon cancer risk (RR = 0.88, 95% CI: 0.81–0.96).
Modest inverse associations with vitamin C and E intakes may be due to high correlations with folate intake, which had a similar inverse association with colon cancer. An inverse association with multivitamin use, a major source of folate and other vitamins, deserves further study.
KeywordsVitamin A Vitamin C Vitamin E Multivitamin Colon cancer Cohort study Pooled analysis
The study was funded by research grants CA55075 from the National Institutes of Health and the National Colorectal Cancer Research Alliance of the Entertainment Industry Foundation.
- 33.Rothman KJ, Greenland S (1998) Modern epidemiology. Lippincott Williams & Wilkins, PhiladelphiaGoogle Scholar
- 44.Cox DR (1972) Regression models and life-tables. J R Stat Soc B 34(2):187–220Google Scholar
- 45.SAS II (1999) SAS/STAT user’s guide, version 8. SAS Institute Inc, CaryGoogle Scholar
- 47.Miettinen O (1985) Theoretical epidemiology. Oxford University Press, New YorkGoogle Scholar
- 51.Anderson T (1984) Introduction to multivariate statistics. Wiley, New YorkGoogle Scholar
- 53.Murray RK, Granner GD, Mayes PA, Rodwell VW (2000) Harper’s biochemistry. McGraw-Hill, New YorkGoogle Scholar
- 60.Kim, D-H, Smith-Warner SA, Spiegelman D, Yaun S-S, Colditz GA, Freudenheim JL, Giovannucci E, Goldbohm RA, Graham S, Harnack L, Jacobs EJ, Leitzmann M, Mannisto S, Miller AB, Potter JD, Rohan TE, Schatzkin A, Speizer FE, Stevens VL, Stolzenberg-Solomon R, Terry P, Toniolo P, Weijenberg MP, Willett WC, Wolk A, Zeleniuch-Jacquotte A, Hunter DJ (2010) Pooled analyses of 13 prospective cohort studies on folate intake and colon cancer. doi: 10.1007/s10552-010-9620-8