Nutrition, Malnutrition, and Behavior

The etiology of chronic, subclinical, and of acute, clinical energy-protein malnutri­ tion is multifactorial, with poverty as the subsoil, the deficiency of specific nutrients as a frequent complicating factor, and infection and parasitism as added stresses. The effects of severe malnutrition are also mUltiple and appear in somatic growth, growth and development of the central nervous system, metabolism, and organ function as well as in behavior. The focus of the present review is on human behavior, with special reference to young children. We regret to have to leave out whole areas (brain development, behavioral animal research) and a large array of specific topics: factors controlling food intake, from physiological mechanisms to food habits; overnutrition leading to obesity; impaired utilization of nutrients due to inborn errors of metabolism, such as phenylketonuria; and in particular, effects of the deficits of specific nutrients such as iodine, iron, and vitamin A. The literature on generalized (energy-protein) malnutrition is unwieldy, with differences in terminology and also in the criteria used to characterize the severity of malnutrition. Finally,