Assessment of risk associated with specific fatty acids and colorectal cancer among French-Canadians in Montreal: a case-control study.
BACKGROUND
Discrepancies in findings on the association between dietary fats and colorectal cancer (CRC) persist, and it is hypothesized that fatty acids (FA) may modulate CRC risk because of their physiological functions.


METHODS
Between 1989 and 1993, a case-control study involving 402 cases and 668 population-based controls was conducted among French-Canadians. Dietary intake was assessed by a food frequency questionnaire.


RESULTS
Oleic acid was the major FA consumed by the study population. A significant inverse association was found among females between CRC and butyrate (OR = 0.57; 95% CI: 0.34-0.96; P = 0.006), alpha-linoleic acid (ALA) (OR = 0.78; 95% CI: 0.46-1.32; P = 0.016), and w-3 FA (OR = 0.84; 95% CI: 0.50-1.41; P = 0.028), comparing the upper to the lower quartiles of intake. An increased risk was associated with arachidonic acid (AA) (OR = 2.03; 95% CI: 1.16-3.54; P = 0.001) among males, and with the w6/w3 ratio (OR = 1.47; 95% CI: 0.86-2.50; P = 0.001) among females. Arachidonic acid was linked with up to fivefold increased risk (OR = 5.33; 95% CI: 2.04-13.95; P = 0.0004 for trend) among men with high vitamin C intake. Females with low carotenoids intake were at elevated risk associated with AA (OR = 4.07; 95% CI: 1.84-8.99; P = 0.003); eicosapentaenoic acid (OR = 3.50; 95% CI: 1.59-7.71; P = 0.015), and docosahexaenoic acid (OR = 5.77; 95% CI: 2.50-13.33; P = 0.002), comparing the upper with the lower quartiles of intake.


CONCLUSIONS
The results of this study suggest that independently of total energy intake, substituting AA by butyrate, ALA, or omega-3 FA may reduce CRC risk. The role of interactions between vitamin C, total carotenoids, and polyunsaturated FA requires further investigation.
Nkondjock
André
A
Département de nutrition, Faculté de médecine, Université de Montréal, Montreal, Quebec, Canada.
Shatenstein
Bryna
B
Maisonneuve
Patrick
P
Ghadirian
Parviz
P
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000208:ethnology / Q000209:etiology*; D004041:Dietary Fats / Q000008:administration & dosage / Q000009:adverse effects*; D005227:Fatty Acids / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D005602:France / Q000208:ethnology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011792:Quebec / Q000453:epidemiology; D012044:Regression Analysis; D018570:Risk Assessment; D012307:Risk Factors
D004041:Dietary Fats; D005227:Fatty Acids