Background: High sucrose intakes are hypothesized to increase colorectal cancer (CRC) risk by several mechanisms, and sucrose intakes have been consistently positively associated with CRC risk in case-control studies. However, all but one prospective study reported a null sucrose-CRC association. The only prospective study to report a positive association was the Iowa Women's Health Study (IWHS) of 35,221 cancer-free Iowa women, aged 55 - 69 years old at baseline in 1986, after four years of follow up.
Materials and methods: To address the discrepant findings in the literature, after 26 years of follow up in the IWHS, we updated and expanded on our earlier reported analyses. During follow up through 2012, 1,731 women were diagnosed with CRC. Baseline dietary intakes were assessed with a Willett semiquantitative food frequency questionnaire. We used multivariable Cox proportional hazards regression models to estimate adjusted hazards ratios (HRs) and their 95% confidence intervals (CI).
Results: For those in the highest relative to the lowest intake quintiles, the adjusted HRs (95% CI) for CRC were 1.04 (0.87-1.23; Ptrend = 0.59) for sucrose, 1.00 (0.82-1.21; Ptrend = 0.67) for sucrose-containing foods, and 1.01, (0.83-1.22; Ptrend = 0.56) for nondairy sucrose-containing foods, respectively. These findings did not differ substantially by colorectal site or according to categories of selected participant characteristics.
Conclusions: Our findings do not support that intakes of sucrose or sucrose-containing foods are substantially associated with CRC risk among older women.
Keywords: Sucrose; colorectal cancer; prospective cohort studies.