A new study has found that changing coffee intake can affect the risk of developing type 2 diabetes. The study is the first observational study to assess the effect of tea and coffee intake on the risk of type 2 diabetes. Researchers Shilpa N. Bhupathiraju of the Harvard School of Public Health and colleagues analyzed three large U.S. cohorts, collecting detailed information on subjects’ diets, lifestyles, medication use and chronic diseases at two- to four-year intervals. The analysis of caffeinated coffee showed that each one-third cup increase in coffee intake per day was associated with an 11% reduction in the risk of developing type 2 diabetes over the subsequent four years compared with no change in coffee intake. Consistent consumption of three or more cups of caffeinated coffee per day resulted in a significant 37% reduction in the risk of developing type 2 diabetes. In contrast, reducing coffee intake by two cups per day increased the risk of developing type 2 diabetes by 17% over the next 4 years. Analysis of decaffeinated coffee showed that while baseline decaffeinated coffee intake was associated with a lower risk of developing type 2 diabetes, changing decaffeinated coffee intake did not affect the risk of developing type 2 diabetes. In addition, changing tea intake did not affect the risk of developing type 2 diabetes, which may be related to the fact that not many people drink tea or change their tea intake. The researchers emphasized that the coffee studied in the study was a small cup (240 ml per cup) of black coffee with little or no sugar rather than a large cup of coffee or blends such as cappuccinos and lattes. Available evidence from observational studies suggests that moderate (6 cups per day) coffee consumption may reduce the risk of type 2 diabetes and cardiovascular disease. The researchers’ analysis suggests that lowering coffee intake may increase the risk of developing type 2 diabetes in a reverse cause-and-effect relationship, i.e., patients with risk factors for type 2 diabetes, such as hypertension, may consciously lower their coffee intake. However, it is important to emphasize that the effect of changes in coffee intake on the risk of developing diabetes may be short-lived. The results of this study need to be further confirmed by prospective studies.