There is a slight problem with the minimum recommended dose of vitamins, i.e. enough to ward off disease. This classification developed in the first half of the twentieth century has been criticized by scientists, because it quickly became clear that the role of nutrients in the body is incredibly varied and in any case is not confined to preventing diseases cause by vitamin deficiency. An analogy might be to suggest that the job of water is to prevent kidney failure on the basis that this condition arises when the body is deprived of fluid.
Conversely, no one would argue that we should drink only enough water to prevent kidney failure. Yet the so-called “minimum recommended dose” of vitamins, as defined for example by the Deutsche Gesellschaft für Ernährung (German Association for Nutrition), is still based on such minimum quantities. In other words, on dosage recommendations that can at most help prevent advanced deficiency symptoms. The physiological optimum intake of vitamins is, in some cases, ten times higher than the minimum recommended dose for the prevention of diseases caused by deficiency.
