Consuming too much caffeine can lead to health issues such as high blood pressure and heart arrhythmias. The artificial sweeteners used in energy drinks can also compromise gut health and reduce good bacteria in the stomach. Regular consumption of artificial sweeteners can encourage sugar dependence and lead to weight gain. The drink is not recommended for people with diabetes or other health issues. The Mayo Clinic recommends only one can per day for adults. However, according to Healing Picks, Monster Zero Ultra is a sugar-free energy drink and as such, does not contain any real sugar.