Physiological and glycemic responses following acute ingestion of a popular functional drink in patients with type 1 diabetes.

Objective: To determine the physiologic and glycemic responses to energy drinks by people with type 1 diabetes.

Methods: In a double-blind randomized comparison of Red Bull, Red Bull Light and a control drink, 16 adults (11 females; average age 31.5 years) with type 1 diabetes and an average glycated hemoglobin (A1C) of 68 mmol/mol were given 750 mL of Red Bull, Red Bull Light and Suso Orange in a random order. During 3 hours, comparisons were made of blood pressure and blood glucose and caffeine levels; 4-choice reaction time (4CRT) and a digit symbol substitution test were used to assess cognitive performance. Mood was measured using the University of Wales Institute of Science and Technology mood adjective checklist.

Results: Consumption of Red Bull and Suso Orange were associated with an early sustained rise in blood glucose, which was augmented by Red Bull (p=0.02). A transient rise in systolic blood pressure (115.9 mm Hg to 124.5 mm Hg and 115.8 mm Hg to 125.9 mm Hg, respectively, both p<0.01) followed consumption of Red Bull and Red Bull Light. There were less consistent changes in diastolic blood pressure and heart rate. Consumption of both energy drinks resulted in modest improvement in performance on the digit substitution test but had no effect on 4CRT. Energy arousal and hedonic tone were influenced transiently only, following the consumption of Suso Orange.

Conclusions: Consumption of energy drinks can result in a significant carbohydrate load for people with diabetes, and patients must consider the need to adjust their insulin regimens appropriately. Caffeine-containing energy drinks can cause a rise in blood pressure, which may be an important consideration for individuals at risk for diabetes-related complications.