Gnc vitamin b-12 - 500 mcg: carbohydrate metabolism and energy support vitamin b-12 is essential for carbohydrate metabolism & energy production and is required for red blood cell formation. Gnc's vitamin b-12 - 500 mcg is kosher and gluten free. Contains a 100-day supply of 100 vegetarian tablets no artificial colors or flavors no preservatives, wheat, soy, or dairy sodium free. Gnc vitamin b-12 500 mcg - 100 tablets (100 servings) vegetarian