Nutritional factors and worldwide incidence of childhood type 1 diabetes

BACKGROUND: Some dietary factors have been associated with the risk of type 1 diabetes in childhood. OBJECTIVE: We investigated relations between dietary energy from major food groups and incidence of childhood type 1 diabetes by using an ecologic study design. DESIGN: We conducted univariate and multivariate regression analysis with incidence rates of type 1 diabetes in the late 1980s and early 1990s among children aged <15 y in 40 countries as the dependent variable and average per capita daily intake of major food items and other socioeconomic, demographic, and geographic risk factors as the independent variables. RESULTS: In the univariate regression model, per capita total energy intake was nonsignificantly associated with type 1 diabetes incidence (r = 0.31, NS), whereas energy from animal sources was associated (r = 0.61, P < 0.01) and energy from vegetal sources was inversely associated (r = -0.35, P < 0.05) with diabetes incidence. Among dietary items of animal origin, meat (r = 0.55, P < 0.001) and dairy products (r = 0. 80, P < 0.0001) were predictors of elevated incidence rates, whereas among dietary items of vegetal origin, cereals (r = -0.64, P < 0. 001) were inverse predictors. In the multivariate analysis, the inverse relation of diabetes incidence with energy from vegetables and the direct correlation with energy from animal sources explained the positive associations of type 1 diabetes incidence with geographic and socioeconomic covariates. CONCLUSION: The incidence of type 1 diabetes varied worldwide according to dietary patterns. In-depth exploration of dietary risk factors during pregnancy and early neonatal life is warranted to confirm whether and to what extent diet cooperates with genetic susceptibility in the early onset of type 1 diabetes.