A recent study conducted by researchers at Umeå University posits a caution for individuals who take cold baths, particularly highlighting the dangers of immersing the head in very cold water. This study, funded by the Swedish Heart and Lung Foundation, suggests that the body’s reaction to sudden immersion in ice-cold water could potentially lead to severe heart rhythm disturbances. The sympathetic nervous system is activated by the cold shock, increasing heart rate, while submerging the head triggers the parasympathetic nervous system, which works to decelerate the heart rate. The simultaneous activation of both systems may elevate the risk of arrhythmias among bathers, marking a significant health warning for cold exposure enthusiasts.