Coffee consumption and type 2 diabetes mellitus

Abstract

The aim of the study was to determine the association between coffee consumption and the risk of type 2 diabetes mellitus. A case-control study included 234 cases with newly confirmed diagnosis of type 2 diabetes mellitus and 468 controls who were free of the disease in 2001. Cases and controls were matched by gender and age (+/-5 years). Data on age, education level, occupation status, marital status, family history of diabetes, lifestyle (dietary habits, smoking habits, coffee consumption, alcohol consumption, physical activity), and stress were collected via a questionnaire. Variables were retained in models as confounders when their inclusion changed the value of the OR by more than 10% in any exposure category. Conditional logistic regression to compute the odds ratio (OR), 95% confidence interval (CI), and P for trend was used. After adjustment for possible confounders (family history of diabetes, body mass index, eating speed, morning exercise, cigarette smoking, years of education, and stress), a statistically significant relationship was observed between type 2 diabetes mellitus and coffee consumption. Individuals consuming four or more cups of coffee per day were at lower risk of 2 diabetes mellitus (OR=0.51; 95% CI, 0.27-0.97) compared to those who consumed one or less than one cup of coffee per day. Habitual coffee consumption of four or more cups per day might be related to the lower risk of type 2 diabetes mellitus.