The effects of malnutrition on intellectual development and learning.

Abstract

IN Colombia, South America, a darkhaired little girl named Maria lives with her family in a shack on a steep hill overlooking the south side of the city of Bogota. She is four years old, yet weighs only 22 pounds and is not yet 3 feet tall. She is lighter and shorter than Virginia who is half her age and is the child of a neighbor. A psychological test revealed that Maria has an IQ of only 69, whereas that of Virginia is normal at 103.' Maria's poor physical growth is due to protein-calorie malnutrition, a lack of food in early childhood including a deficiency in high quality protein. Was this malnutrition also a cause of her retarded intellectual development? At the Denver General Hospital in Colorado, Dr. H. Peter Chase reported that 19 children admitted between 1962 and 1967 at less than a year of age with generalized undernutrition scored poorly on intelligence tests when tested some years later. The mean Development Quotient of the 19 previously malnourished children was 82.1, whereas 16 children chosen as controls on the basis of age, sex, birth weight, race and being born and followed in the same hospital, had a mean Development Quotient of 99.41 These two examples,2 one from the slums of a developing country and one from a corner of this wealthy nation, may suggest that dietary deficiencies in young children cause a retardation in intellectual development and mental functioning. Let us examine the evidence. We need first, however, to be clear about what form of malnutrition is being considered.