In their classic view, antioxidants are substances that protect cells from damage caused by oxygen radicals / oxidative stress. A distinction is made between “enzymatic” and “non-enzymatic” mechanisms. The enzymatic protective enzymes are various enzymes that can very specifically neutralize harmful compounds. These include, for example, catalase for neutralizing hydrogen peroxide or superoxide dismutase for neutralizing the very aggressive superoxide anions. These enzymes require zinc, selenium or manganese to fulfill their tasks.
The second group of antioxidant-active ingredients, known as classic radical scavengers, are compounds such as vitamin C, E, glutathione or co-enzyme Q10. High-dose, water-soluble vitamin C and fat-soluble vitamin E can neutralize the free radicals directly by releasing electrons by reducing the aggressive oxygen compounds and thus converting them into a stable and non-cell-damaging form. In addition, vitamin C can regenerate oxidized (“used”) vitamin E. Particularly important in this group is the co-enzyme Q10, which performs its function on the inner mitochondrial membrane, i.e. at the place within the cell where particularly large numbers of free radicals can arise as part of the respiratory chain to generate energy, for example during exercise.