Special K contains 2% or less of sugar, salt, malt flavouring, sucralose, natural and artificial flavour, and BHT for freshness. Vitamins and minerals include vitamin C (ascorbic acid), vitamin E (alpha tocopherol acetate), niacinamide, reduced iron, vitamin B (pyridoxine hydrochloride), vitamin B (thiamin hydrochloride), vitamin A (palmitate), vitamin B (riboflavin), folic acid, and vitamin B In the US, Special K provides meal replacements in two different forms, protein meal bars and protein shakes. There are eleven varieties of Special K Protein Meal Bars: Mocha Crunch Protein, Chocolate Peanut Butter, Strawberry, Double Chocolate, Chocolatey Chip, Honey Almond, Cranberry Walnut, Chocolate Caramel, Chocolatey Brownie,
Vitamin C efficiency decreases as amounts increase. Intravenous administration bypasses this. Doing so makes it possible to achieve plasma concentrations of 5 to 10 millimoles/liter (mmol/L), which far exceed the approximately 0.2 mmol/L limit from oral consumption. The theories of mechanism are contradictory. At high tissue concentrations ascorbic acid is described as acting as a pro-oxidant, generating hydrogen peroxide (HO) to kill tumor cells. The same literature claims that ascorbic acid acts as an antioxidant, thereby reducing the adverse effects of chemotherapy and radiation therapy. Research continues in this field, but a 2014 review concluded: "Currently, the use of high-dose intravenous vitamin