High GL Diet Raises Breast Cancer Risk

MILAN, ItalyA high glycemic load (GL) diet may increase the risk of breast cancer, particularly in premenopausal and normal weight women (Am J Clin Nutr. 2007;86(4):1160-6). Researchers from Italys National Cancer Institute examined data from the Hormones and Diet in the Etiology of Breast Tumors (ORDET) Study, which included a cohort of women from Northern Italy enrolled between 1987 and 1992. Dietary glycemic index (GI) and GL in relation to breast cancer risk were evaluated in 8,926 cohort women, including 289 with breast cancer.

The relative risk (RR) of breast cancer in the highest vs. lowest quintiles of GI and GL was 1.57 and 2.53, respectively. Total carb intake was not associated with a higher risk of breast cancer; however, high carbohydrates from high-GI foods was associated. After categorizing the women by menopausal status and body mass index (BMI), the increased risk of dietary GL was confined to those who were premenopausal (RR 3.89) and those of normal BMI (RR 5.79). The researchers suggested breast cancer disease risk is linked to insulinemia, sex hormone bioavailability and insulin-like growth factor.