Author Interviews, Diabetes, Diabetologia, Nutrition / 28.02.2015

Professor Daniela Jakubowicz MD Diabetes Unit. E. Wolfson Medical Center Sackler Faculty of Medicine, Tel Aviv University and Tel Aviv Medical  Center Interview with: Professor Daniela Jakubowicz MD Diabetes Unit. E. Wolfson Medical Center Sackler Faculty of Medicine, Tel Aviv University and Tel Aviv Medical  Center Israel MedicalResearch: What is the background for this study? What are the main findings? Professor Jakubowicz: Obesity epidemic have lead to alarming rise of type 2 diabetes. It is estimated that more than 382 million worldwide have diabetes, predominately type 2 diabetes. In these persons the cardiovascular disease is the leading complication, carrying 10 to 20-fold increase in the risk compared with persons without diabetes. It has been shown that large glucose peaks after meals along the day, are strongly associated with increased a risk for cardiovascular complications. Therefore the mitigation of glucose excursions after meals becomes a major target in the treatment of type 2 diabetes in order to improve glucose balance and prevent complications. Accordingly, dietary modification focused on reduction post meal glucose peaks is needed. Even though still there is no consensus on which of the dietary strategies (i.e. low-fat diet, Mediterranean and low-carbohydrate, higher fiber, low GI glycemic index meals, etc.) is more suitable in improving post-meal glycemic responses along the day. However in none of these interventions has been considered that modifying the meal timing pattern or daily caloric distribution, may lead to improved post-meal glycemic responses in type 2 diabetic patients. The circadian clock genes existing in the pancreatic β-cells, gut, liver and in skeletal muscle, regulate the diurnal (circadian) oscillation of post-meal glucose responses. In fact, post-meal glycemia displays a clear diurnal variation: it is higher and more prolonged in the evening than in the morning. Meal timing schedule, on the other hand, exerts strong controlling influence on circadian clock regulation, thereby influencing the variation and degree of the post meal glycemic elevations. Indeed meal timing non-aligned with the clock gene circadian rhythms, such as breakfast skipping or high-energy intake at dinner, is associated with obesity, higher HbA1C and poor glycaemic control in type 2 diabetes. To clarify the impact of meal timing and composition on overall post-meal glucose responses, we tested the effect of 2 isocaloric diets with different meal timing one with high energy breakfast (704 kcal), mid-sized lunch (600 kcal) and reduced dinner (200 kcal) and other with similar lunch but reduced breakfast (704 kcal) and high energy dinner(704 kcal). The study clearly demonstrated that in type 2 diabetic patients, a diet consisting on high energy breakfast, and reduced dinner, resulted in significantly reduced glucose response after meals and lower overall plasma glucose levels along the entire day, when compared to a diet with the same caloric content but inverse distribution: breakfast (200 kcal) , lunch (600 kcal) and high energy dinner(704 kcal). Moreover, when we compared the glucose response after high energy meal consumed at breakfast (700 kcal) versus in the dinner (700 kcal), it comes out that the glucose response was significantly higher after dinner than after breakfast. It shows that just by changing the time of the high energy meal we may achieve significant reduction in the glucose response. (more…)