Associations of Nut Intakes with Incident Sporadic Colorectal Adenoma: A Pooled Case-Control Study

Abstract

Introduction: Consumption of nuts, which contain multiple anti-carcinogenic components, has been inversely associated with colorectal cancer (CRC), particularly among women, but has not been investigated in relation to colorectal adenoma, the immediate precursor to most CRCs.Methods: We pooled data from three case-control studies of incident, sporadic colorectal adenoma (n = 785 cases, 2107 controls) in which dietary intakes were assessed using food frequency questionnaires, and analyzed the data using multivariable unconditional logistic regression.Results: Among men and women combined, the multivariable-adjusted odds ratios (OR) and 95% confidence intervals (CI) for the association of total nut product (all nuts and peanut butter combined) intakes, for those who consumed 0.5–1.5, 2.0–5.5, and ≥6 servings/week relative to no nut consumption were 0.81 (0.58, 1.12), 0.86 (0.61, 1.23), and 0.93 (0.65, 1.31), respectively. However, among women, the corresponding ORs and 95% CIs were 0.62 (0.40, 0.97), 0.57 (0.35, 0.94), and 0.78 (0.48, 1.25), respectively.Conclusions: These results suggest that moderate nut consumption may be associated with lower risk for colorectal adenoma, primarily among women.