Sarcouncil Journal of Applied Sciences Aims & Scope

Abstract: This study was conducted to determine the acute effects of drinking caffeine on blood sugar levels and responses of the autonomic nervous system in healthy people. The findings proved that the consumption of caffeine at 5 mg/kg body weight produces evident and temporary physiological changes in metabolic and autonomic equilibrium. The blood glucose and insulin levels were found to be significantly high after taking caffeine, with the highest level at 60 minutes, and then there was a partial reduction at 120 minutes and the leveled at 60 was as a result of the acute metabolic response to the caffeine intake and compensation by the body. Also, there was a temporary increase in the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), which implies a short-term decrease in the insulin sensitivity within the range of the peak response. At the cardiovascular level, the consumers of caffeine achieved a significant rise in HR and systolic and diastolic BP. Moreover, an increase was found in the LF/HF ratio calculated by analyzing the heart rate variability, indicating the stimulation of the sympathetic nervous system and its temporary domination over the parasympathetic activity , In contrast, no significant changes in physiology could be observed in the placebo group during the period of the study, thus confirming that the results were directly due to caffeine intake.Collectively these findings suggest that caffeine is a metabolic and autonomic stimulant that produces acute but reversible physiological effects in healthy individuals, with pronounced ability of the body to restore remission of a homeostatic imbalance after the discontinuation of this effect. These results provide an improvement in the knowledge of the short-term effects of caffeine consumption, especially in people who are at greater risk of metabolic or cardiovascular problems, and also note that the possible long-term effects of regular caffeine intake need to be studied in the future.