The use of beverages containing caffeine has increased significantly in recent years due to their stimulant effects. The aim of this study was to determine the possible adverse effects of caffeine and taurine on young adults’ cardiovascular systems using linear and nonlinear parameters for this analysis. This study was carried out with 56 students from Aydın Adnan Menderes University. The participants were divided into four main groups: caffeine, taurine, caffeine + taurine, and a control. Blood pressure and electrocardiogram measurements were performed before the ingredients were consumed. After 30 and 60 min, the measurements were repeated. Linear and nonlinear analyses were performed on the heart rate variability data 60 min after consumption. Compared with taurine and the combination of caffeine + taurine, caffeine was found to have the most adverse effects on the hemodynamic parameters and the linear and nonlinear parameters of heart rate variability in the young adult participants. It was also found that the presence of taurine may have repressed the adverse effects of caffeine.