Relationship Between Dairy Product Consumption and Incidence of IDDM in Childhood in Italy

OBJECTIVE To test the hypothesis that the consumption of dairy products, including fluid cows' milk and cheese, is related to the incidence of insulin-dependent diabetes mellitus (IDDM), we correlated incidence rates in children 0–14 years of age with cows' milk and cheese consumption in nine regions of a single country, Italy.

RESEARCH DESIGN AND METHODS Data on the incidence of IDDM were derived from the only nine Italian regions where primary and secondary sources of ascertainment were available for 1991. Data on fluid cows' milk and cheese consumption in the corresponding year in each region were obtained from the National Institute of Statistics.

RESULTS The correlation between fluid milk consumption and incidence of IDDM in Italy was 0.84 (P < 0.004, Poisson regression analysis). Cheese consumption was not related to IDDM incidence.

CONCLUSIONS The results indicate that there is a relationship, even in a single country, between dairy product consumption and the incidence of IDDM that is confined to fluid milk consumption. Cows' milk may contain a triggering factor for the development of diabetes, but the high incidence of IDDM in Sardinia and in other countries worldwide cannot be explained simply by the quantity of fluid cows' milk consumed.