Red Bull Zero contains the same functional ingredients as Red Bull Energy Drink (caffeine, taurine and some B-group vitamins) but is made with low- and non-caloric sweeteners; erythritol, sucralose and monk fruit extract. Monk fruit extract is a non-caloric sweetener used in a wide range of products, like juices, soft drinks, candies and desserts.
Caffeine helps to improve concentration and increase alertness.
B-group vitamins (niacin, pantothenic acid, B6, B12) contribute to the reduction of tiredness and fatigue.
Taurine, an amino acid that occurs naturally in the human body, is involved in a range of processes including regulation of water/electrolyte balance at the cellular level.
For more information, refer to the nutrition label on the can and visit the link for the Zero ingredient page.