Carbohydrate, glycemic index, and glycemic load and colorectal adenomas in the Prostate, Lung, Colorectal, and Ovarian Screening Study

• Published in: The American journal of clinical nutrition 2006-11, Vol.84 (5), p.1184-1192
• Main Authors: Flood, Andrew, Peters, Ulrike, Jenkins, David JA, Chatterjee, Nilanjan, Subar, Amy F, Church, Timothy R, Bresalier, Robert, Weissfeld, Joel L, Hayes, Richard B, Schatzkin, Arthur
• Format: Article
• Language: English
• Subjects: adenoma; Adenoma - diagnosis; Adenoma - epidemiology; Adenoma - etiology; Adenomatous Polyps - diagnosis; Adenomatous Polyps - epidemiology; Adenomatous Polyps - etiology; Aged; Biological and medical sciences; carbohydrate intake; carbohydrate loading; Case-Control Studies; Cohort Studies; Colorectal cancer; colorectal neoplasms; Colorectal Neoplasms - diagnosis; Colorectal Neoplasms - epidemiology; Colorectal Neoplasms - etiology; Confidence Intervals; diet; Dietary Carbohydrates - administration & dosage; Dietary Carbohydrates - adverse effects; disease prevalence; epidemiological studies; Feeding Behavior; Feeding. Feeding behavior; Female; food frequency questionnaires; Fundamental and applied biological sciences. Psychology; glycemic effect; Glycemic Index; human diseases; Humans; Hyperglycemia - complications; hyperinsulinemia; Logistic Models; Lung cancer; Male; Mass Screening; Medical screening; men; Middle Aged; Multivariate Analysis; neoplasms; Nutrition Assessment; Odds Ratio; Ovarian cancer; pathogenesis; probability analysis; Prostate cancer; Prostate, Lung, Colorectal, and Ovarian Screening Study; Risk Assessment; Risk Factors; Sigmoidoscopy; Surveys and Questionnaires; United States - epidemiology; Vertebrates: anatomy and physiology, studies on body, several organs or systems; women
• ISSN: 0002-9165; 1938-3207
• DOI: 10.1093/ajcn/84.5.1184

BACKGROUND: It is possible that high-glycemic-load diets, through their hyperinsulinemic effects, can increase the risk of colorectal cancer. OBJECTIVE: We analyzed data from a cancer screening study to determine whether persons with high-glycemic-load diets would be at an increased risk of distal adenomas. DESIGN: We included subjects with no prior adenoma or cancer from the Prostate, Lung, Colorectal, and Ovarian screening trial and whose results from flexible sigmoidoscopy exams indicated either no lesions (n = 34 817) or >=1 distal adenoma (n = 3696). We used a 137-item food-frequency questionnaire to assess usual dietary intake over the preceding 12 mo. Using logistic regression analysis, we calculated, separately for men and women, prevalence odds ratios (ORs) and 95% CIs of sigmoidoscopy-detected, distal adenomas for quintiles of energy-adjusted dietary carbohydrate, glycemic index, and glycemic load. RESULTS: ORs decreased with increasing intakes of carbohydrate for both the men and the women in unadjusted models, but these associations were attenuated in multivariate-adjusted models. Among the men, the association remained significant after adjustment (OR: 0.71; 95% CI 0.60, 0.84; P for trend < 0.0001), but in the women it did not (OR: 0.89; 95% CI: 0.73, 1.10; P for trend = 0.30). The results for glycemic index showed no associations in either men or women. Results for glycemic load closely mirrored those for carbohydrate. CONCLUSION: Despite expectations that increasing glycemic load and glycemic index would increase the risk of adenoma, we observed no association in women and even an inverse association in men.