@article{3045385,
    title = "DIETARY-INTAKE OF FIBER AND DECREASED RISK OF CANCERS OF THE COLON AND
RECTUM - EVIDENCE FROM THE COMBINED ANALYSIS OF 13 CASE-CONTROL STUDIES",
    author = "HOWE, GR and BENITO, E and CASTELLETO, R and CORNEE, J and ESTEVE, J and and GALLAGHER, RP and ISCOVICH, JM and JIAO, DA and KAAKS, R and KUNE, GA and and KUNE, S and LABBE, KA and LEE, HP and LEE, M and MILLER, AB and and PETERS, RK and POTTER, JD and RIBOLI, E and SLATTERY, ML and and TRICHOPOULOS, D and TUYNS, A and TZONOU, A and WHITTEMORE, AS and and WUWILLIAMS, AH and ZHENG, S",
    journal = "Journal of the National Cancer Institute. Monographs",
    year = "1992",
    volume = "84",
    number = "24",
    pages = "1887-1896",
    publisher = "NATL CANCER INSTITUTE",
    issn = "1052-6773",
    doi = "10.1093/jnci/84.24.1887",
    abstract = "Background: Colorectal cancer is a major public health problem in both
North America and western Europe, and incidence and mortality rates are
rapidly increasing in many previously low-risk countries. It has been
hypothesized that increased intakes of fiber, vitamin C, and beta
carotene could decrease the risk of colorectal cancer. Purpose: The
objective of this study was to examine the effects of fiber, vitamin C,
and beta-carotene intakes on colorectal cancer risk in a combined
analysis of data from 13 case-control studies previously conducted in
populations with differing colorectal cancer rates and dietary
practices. The study was designed to estimate risks in the pooled data,
to test the consistency of the associations across the studies, and to
examine interactions of the effects of the nutrients with cancer site,
sex, and age. Methods: Original data records for 5287 case subjects with
colorectal cancer and 10 470 control subjects without disease were
combined. Logistic regression analysis was used to estimate relative
risks and confidence intervals for intakes of fiber, vitamin C, and beta
carotene, with the effects of study, sex, and age group being adjusted
by stratification. Results: Risk decreased as fiber intake increased;
relative risks were 0.79, 0.69, 0.63, and 0.53 for the four highest
quintiles of intake compared with the lowest quintile (trend, P<.0001).
The inverse association with fiber is seen in 12 of the 13 studies and
is similar in magnitude for left- and right-sided colon and rectal
cancers, for men and for women, and for different age groups. In
contrast, after adjustment for fiber intake, only weak inverse
associations are seen for the intakes of vitamin C and beta carotene.
Conclusion: This analysis provides substantive evidence that intake of
fiber-rich foods is inversely related to risk of cancers of both the
colon and rectum. Implications: If causality is assumed, we estimate
that risk of colorectal cancer in the U.S. population could be reduced
about 31% (50000 cases annually) by an average increase in fiber intake
from food sources of about 13 g/d, corresponding to an average increase
of about 70%."
}