A study of university students found drinking one 250ml can of the sugar-free version of the energy drink that 'gives you wings' increased the 'stickiness' of the blood and raised the risk of life-threatening clots. Researcher Dr Scott Willoughby said: 'One hour after they drank Red Bull, ) were no longer normal. It is dangerous to take it if you do not engage in physical exercise afterwards, since its energizing function accelerates the heart rate and can cause a sudden attack. You run the risk of undergoing a cerebral hemorrhage, because RED BULL contains components that dilute the blood! One of the main components of Red BULL is the B12 vitamin, which recovers coma patients! riggers off symptoms in the form of a series of irreversible nervous and neuronal diseases.