RT Journal Article SR Electronic T1 Effect of meal composition and alcohol consumption on postprandial glucose concentration in subjects with type 1 diabetes: a randomized crossover trial JF BMJ Open Diabetes Research & Care JO BMJ Open Diab Res Care FD American Diabetes Association SP e002399 DO 10.1136/bmjdrc-2021-002399 VO 9 IS 1 A1 Alia García A1 Vanessa Moscardó A1 Agustín Ramos-Prol A1 Julián Díaz A1 Miguel Boronat A1 Jorge Bondia A1 Paolo Rossetti YR 2021 UL http://drc.bmj.com/content/9/1/e002399.abstract AB Introduction Meal composition is known to affect glycemic variability and glucose control in type 1 diabetes. The objective of this work was to evaluate the effect of high carbohydrate meals of different nutritional composition and alcohol on the postprandial glucose response in patients with type 1 diabetes.Research design and methods Twelve participants were recruited to this randomized crossover trial. Following a 4-week run-in period, participants received a mixed meal on three occasions with the same carbohydrate content but different macronutrient composition: high protein-high fat with alcohol (0.7g/kg body weight, beer), high protein-high fat without alcohol, and low protein-low fat without alcohol at 2-week intervals. Plasma and interstitial glucose, insulin, glucagon, growth hormone, cortisol, alcohol, free fatty acids, lactate, and pH concentrations were measured during 6 hours. A statistical analysis was then carried out to determine significant differences between studies.Results Significantly higher late postprandial glucose was observed in studies with higher content of fats and proteins (p=0.0088). This was associated with lower time in hypoglycemia as compared with the low protein and fat study (p=0.0179), at least partially due to greater glucagon concentration in the same period (p=0.04). Alcohol significantly increased lactate, decreased pH and growth hormone, and maintained free fatty acids suppressed during the late postprandial phase (p<0.001), without significant changes in plasma glucose.Conclusions Our data suggest that the addition of proteins and fats to carbohydrates increases late postprandial blood glucose. Moreover, alcohol consumption together with a mixed meal has relevant metabolic effects without any increase in the risk of hypoglycemia, at least 6 hours postprandially.Trial registration number NCT03320993.Data are available upon reasonable request. The data are available on request from the corresponding author. Paolo Rossetti (prossetti73@gmail.com).