Dietary carbohydrate, glycemic index, and glycemic load and the risk of colorectal cancer in the BCDDP cohort

Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, 1300 South Second Street, Suite 300, Minneapolis, MN 55454, USA.
Cancer Causes and Control (Impact Factor: 2.74). 11/2007; 18(8):853-63. DOI: 10.1007/s10552-007-9030-8
Source: PubMed


There is considerable support for associations between insulin and IGF-I levels and colorectal cancer. Diet may relate to colorectal cancer through this mechanism, for example, diets high in glycemic index, glycemic load and/or carbohydrate are hypothesized to increase insulin load and the risk of insulin resistance, hyperinsulinemia. Case-control studies support this hypothesis, but prospective cohorts have had mixed results.
In the Breast Cancer Detection Demonstration Project (BCDDP) follow-up cohort of 45,561 women, we used Cox proportional hazards regression to assess the distribution of 490 incident cases of colorectal cancer ascertained during 8.5 years of follow-up across quintiles of carbohydrate intake, glycemic index, and glycemic load. We also stratified by combined BMI and physical activity levels.
We found reductions in colorectal cancer risk for diets high in carbohydrate (RR for Q5 vs. Q1 = 0.70, 95% CI: 0.50-0.97) and glycemic index (0.75, 95% CI: 0.56-1.00), and no significant association for glycemic load (0.91, 95% CI: 0.70-1.20). Inverse associations were weakest in normal weight active persons. The inverse association for glycemic index was strongest for the portion from dairy food.
These results do not support an association between diets high in carbohydrate, glycemic index or glycemic load and colorectal cancer.

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    • "Population M, F Franceschi et al, 2001 (53) Italy CC 1953 4154 Hospital M, F Levi et al, 2002 (54) Switzerland CC 323 661 Hospital M, F Terry et al, 2003 (63) Canada Cohort NBSS 616 49124 F Higginbotham et al, 2004 (64) USA Cohort WHS 174 38451 F Michaud et al, 2005 (20) USA Cohort HPFS, NHSI 1809 131349 M, F Larsson et al, 2007 (65) Sweden Cohort SMC 870 61433 F McCarl et al, 2006 (40) USA Cohort IWHS 954 35197 F Murtaugh et al, 2006 (29) USA CC KPMCP 1698 1861 Population M, F Strayer et al, 2007 (55) USA Cohort BCDDP 490 45561 F Weijenberg et al, 2007 (56) Netherlands Cohort NCS 1643 120852 M, F Pancreas Michaud et al, 2002 (36) USA Cohort NHS 180 88802 F Johnson et al, 2005 (42) USA Cohort IWHS 190 34699 F Silvera et al, 2005 (66) "
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