Nutrition and cognitive function.

The work of the Medical Research Council Dunn Nutrition Unit, Cambridge, on the influence of early diet on the development of preterm infants is reviewed. Then further consideration is given to the implication of the findings. Malnutrition during a sensitive period may result in disease in adult life, and studies strongly suggest the development of the brain and retina can be affected. This may be due to the lack of essential fatty acids, and will particularly involve premature babies born at a time when cell membrane development is especially vulnerable. These findings must sometimes be viewed with caution, as genetic and environmental influences can be paramount. There are many reasons to favour breast feeding, rather than giving formula feeds, including improved cognition and visual function. For example breast milk contains docosahexaenoic acid and arachidonic acid, essential for normal brain development, and often absent or in short supply in formula feeds. Although the advantages in developmental status may be due, in part anyhow, to factors such as the mother's ability and education, and to the child being given greater opportunities, the evident importance of the composition of human breast milk cannot be denied. Formula feeds do contain a higher nutrient value than breast milk, which can result in improved height and weight of infants fed in this way: if it is necessary to use them the challenge for future research is to improve their composition. Although this may be of more importance for premature babies, term babies can also be affected; this has both medical and social implications.