Dietary fiber, source foods and colorectal cancer risk: the Fukuoka Colorectal Cancer Study.
OBJECTIVE
Despite much evidence from laboratory work, epidemiological evidence remains elusive regarding the role of dietary fiber in colorectal carcinogenesis. We investigated associations of dietary fiber and source foods with colorectal cancer risk in the Fukuoka Colorectal Cancer Study, a community-based case-control study.


METHODS
The study subjects were 816 incident cases of colorectal cancer and 815 community controls. Nutrient and food intakes were estimated on the basis of a computer-assisted interview regarding 148 dietary items. Odds ratios of colorectal cancer according to quintile categories of energy-adjusted intakes of dietary fiber and food groups were obtained with adjustment for non-dietary factors and dietary intakes of calcium and n-3 fatty acids.


RESULTS
Total, soluble and insoluble dietary fibers were not measurably associated with overall risk or subsite-specific risk of colorectal cancer. By contrast, rice consumption was associated with a decreased risk of colorectal cancer (trend p = 0.03), particularly of distal colon and rectal cancer (trend p = 0.02), and high intake of non-rice cereals tended to be related to an increased risk of colon cancer (trend p = 0.07). There was no association between vegetable consumption and colorectal cancer, whereas individuals with the lowest intake of fruits tended to have an increased risk of colorectal cancer.


CONCLUSIONS
The present study did not corroborate a protective association between dietary fiber and colorectal cancer, but suggested a decreased risk of distal colorectal cancer associated with rice consumption.
Uchida
Kazuhiro
K
Department of Preventive Medicine, Graduate School of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka, Japan.
Kono
Suminori
S
Yin
Guang
G
Toyomura
Kengo
K
Nagano
Jun
J
Mizoue
Tetsuya
T
Mibu
Ryuichi
R
Tanaka
Masao
M
Kakeji
Yoshihiro
Y
Maehara
Yoshihiko
Y
Okamura
Takeshi
T
Ikejiri
Koji
K
Futami
Kitaroh
K
Maekawa
Takafumi
T
Yasunami
Yohichi
Y
Takenaka
Kenji
K
Ichimiya
Hitoshi
H
Terasaka
Reiji
R
D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D004043:Dietary Fiber / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D015994:Incidence; D033162:Incidental Findings; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012275:Oryza; D018570:Risk Assessment; D011795:Surveys and Questionnaires