Dietary Glycemic Index, Brain Function and Food Intake in Patients With Type 1 Diabetes Mellitus

Processed carbohydrates cause rapid changes in blood sugar and have been associated with overeating and obesity. We have shown that test meals high in processed carbohydrate affect brain areas involved in addiction, craving and overeating. It is unknown whether the changes in blood sugar or the associated higher insulin levels mediate this brain activation and its likely adverse effects. Answering this question is important for patients with type 1 diabetes who have elevated risks of obesity and disordered eating: If blood sugar is the causal mechanism, optimal insulin coverage should be protective. If insulin is the causal mechanism, however, a diet high in processed carbohydrate could predispose to overeating and weight gain, as this diet requires higher insulin doses. To disentangle these factors, we will study brain activation and relevant blood markers in 15 men with diabetes. In 4 sessions, we will examine meals with differential carbohydrate properties while giving insulin infusions.