Objective: The study was carried out to determine whether coffee or tea consumption by the child before diagnosis of diabetes or consumption by parents at the time of the child's conception or during pregnancy was associated with the risk for childhood type 1 diabetes.
Design: Case-control study.
Setting and subjects: All diabetic children younger than 15 years, and diagnosed from September 1986 to the end of April 1989, were invited to participate. 600 newly diagnosed diabetic children and 536 randomly selected population-based children, and their parents took part in a nationwide study.
Results: The risk for type 1 diabetes was increased in the children who consumed at least 2 cups of coffee daily [odds ratio (OR) 1.94, 95% confidence interval (CI) 1.08-3.47], and in the children who consumed 1 cup of tea (OR 1.69, 95% CI 1.21-2.37) or at least 2 cups daily (OR 2.59, 95% CI 1.60-4.18) when adjusted for mother's education, child's age and child's sex. Parents' consumption of coffee or tea during conception of the child and mother's coffee consumption during pregnancy did not affect the risk for diabetes in the children.
Conclusions: We observed an increased risk for type 1 diabetes in the children who consumed coffee or tea regularly.