Gnc b-complex energy: supports metabolism and energy production gnc b-complex energy combines 8 key b-vitamins with 100 mg of caffeine to fuel mental alertness and performance. B-vitamins help to convert food to fuel and metabolism and energy production. Because your body cannot store b vitamins for long periods of time, providing your body with adequate amounts is very important. Caffeine also has thermogenic properties to calorie burning. Gnc b-complex energy contains b-vitamins to metabolic processes in the body features 100 mcg vitamin b-12 for energy production and red blood cells includes caffeine to focus and mental alertness gluten free, no sugar, no corn, no soy, no dairy, sodium free no artificial colors, no artificial flavors. Gnc b-complex + energy vitamin b - 120 capsules (120 servings)