Our goal was to investigate if food of small particle size increases the gastric emptying rate and lessens the fall in postprandial blood glucose in seven subjects with Type 1 diabetes and gastroparesis. Two solid meals of identical composition but of different particle size, with 5MBq (99m)Tc added to the meals, were ingested in randomized order in seven subjects with Type 1 Diabetes Mellitus and gastroparesis and seven healthy subjects. During 180min blood glucose and insulin concentrations were measured and gastric emptying of the ingested meals was registered by a gamma camera. The lag phase in the stomach was significantly shorter, the radioactivity remaining in the stomach after 120min (T(120)) was significant less and the postprandial blood glucose dip was less and of shorter duration after a small particle (SP) meal, compared to a large particle (LP) meal in diabetic subjects. Gastric emptying did not differ significantly between groups after an SP meal. Food of small particle size increases the gastric emptying rate and reduces the postprandial blood glucose dip in both magnitude and duration in Type 1 diabetic subjects with gastroparesis, which is likely to be of importance in achieving good metabolic control.