Antioxidant and DNA methylation-related nutrients and risk of distal colorectal cancer.
OBJECTIVE
To investigate the relationship between antioxidant nutrients (vitamins C and E, beta-carotene, selenium) and DNA methylation-related nutrients (folate, vitamins B6 and B12) and distal colorectal cancer risk in whites and African Americans and to examine intakes from food only versus total (food plus dietary supplements) intakes.


METHODS
Data are from the North Carolina Colon Cancer Study-Phase II, a case-control study of 945 distal colorectal cancer (including sigmoid, rectosigmoid, and rectum) cases and 959 controls. In-person interviews captured usual dietary intake and various covariates. Multivariate logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (95% CI).


RESULTS
High intakes of each antioxidant and DNA methylation-related nutrient were significantly associated with lower risk in whites. In African Americans, the highest category of selenium from food only had a marginally significant inverse association with distal colorectal cancer risk (Q4 vs. Q1 OR: 0.55, 95% CI 0.29-1.02). Supplements did not provide additional risk reduction beyond intakes from food.


CONCLUSIONS
Our findings provide evidence that antioxidant and DNA methylation-related nutrients may lower the risk of distal colorectal cancer in whites, and selenium may lower risk in African Americans. Optimal micronutrient intakes from food alone may be more beneficial than supplementation.
Williams
Christina Dawn
CD
Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, McGavran-Greenberg Hall, Chapel Hill, NC 27599, USA. cdpayne@email.unc.edu
Satia
Jessie A
JA
Adair
Linda S
LS
Stevens
June
J
Galanko
Joseph
J
Keku
Temitope O
TO
Sandler
Robert S
RS
D000328:Adult; D001741:Black or African American; D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage*; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology* / Q000208:ethnology / Q000235:genetics* / Q000517:prevention & control; D019175:DNA Methylation; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D044465:White People
D000975:Antioxidants