The Association between Dietary Energy Density and the Risk of Type 2 Diabetes: Tehran Lipid and Glucose Study

Dietary energy-dense foods predispose to obesity and may be associated with risk of type 2 diabetes; therefore, the aim of our study was to investigate the association between dietary energy density (DED) and the risk of type 2 diabetes. In this matched nested case-control study, 178 new onset cases of diabetes were selected from among participants of the Tehran Lipid and Glucose Study, and followed for over 9 years. Each case was randomly matched with 3 controls from among participants who had not developed diabetes. Dietary intakes were determined using a valid and reliable food frequency questionnaire. DED was calculated as energy intakes (kcal) from foods and beverages divided by the weight (grams) of foods. The mean ages of participants were 43±6.5 and 44.5±12 years, in women and men respectively. Individuals with higher DED had higher calories, total fat, carbohydrate and processed meat intakes and lower fruit and vegetable intakes in men and women (P<0.05). Energy density was positively associated with incident diabetes in women, after adjustment for diabetes risk factors and total calorie intake (OR: 2.28, P trend=0.02) or total fat intake (OR: 2.15, P trend=0.03), an association which was not significant in men. In this nested case-control study, there was positive association between DED and risk of type 2 diabetes in women.