ce in the CRSP studies zinc intakes were frequently low. The question was raised, but not resolved, of the possibility of absorption of zinc from the colon. Another point is that zinc plays a special role in the response to infections, and it has often been suggested that infections and infestations are a major factor in the production of stunting. The requirements of nutrients for growth may be different from the requirements for counteracting infection, so it could be dangerous to extrapolate to the Third World estimates of requirements obtained in affluent countries. It was also pointed out that in many experimental studies male animals were found to be more susceptible to zinc deficiency than females (Golden). In the CRSP studies, girls seemed to do better than boys and get fewer infections in the preschool years (Neumann).
Lastly, it was suggested that fat intake, which is low in the vegan and Third World diets, may be important because there is evidence of obligatory fat oxidation in the postabsorptive state (Jéquier).
The conclusion from these three studies, and from earlier intervention trials, is that stunting occurs in children whose diets are low in animal protein and in factors associated with animal protein in foods. This conclusion can best be tested by intervention studies. The question was not discussed, whether there would be any value in setting up studies designed to elucidate which particular nutrients are involved. From a scientific point of view such studies would be very important. From the practical point of view, since people eat foods not nutrients, the lesson would be that there is a need for improving the quality as well as the quantity of the diets of preschool children.