Red Bull Sugarfree contains caffeine that helps to improve concentration and increase alertness, contains B-group vitamins niacin pantothenic acid B6 B12 which contribute to the reduction of tiredness and fatigue, contains taurine an amino acid that occurs naturally in the human body and is involved in regulation of water and electrolyte balance at the cellular level, uses a combination of low and no calorie sweeteners instead of sugars, water is the main ingredient.