Functional Consequences of Malnutrition

Abstract

Human factors likely to be related to dietary intake and regarded as important across cultures and time are disease response, reproductive competence, cognitive function, work output, and social and behavioral habits. Functional failure in these domains is seen as having profound effects on health and demography. Most investigators who have examined issues of food intake and human function have accepted some indicator of an individual's body size as a measure for malnutrition. Anthropometric indicators, such as weight/age, weight/height, or height/age, are most commonly used. Unfortunately, body size reflects many other factors in addition to malnutrition, Because food intake is seldom known, it is difficult to estimate the amount of variation in size due either to nutrition or to other factors, The tacit assumption is that, within a given milieu, conditioning factors are reasonably constant and that differences in size not attributable to conditioning factors are due to differences in intake of nutrients. Thus, persons of larger stature generally appear to function better than persons of smaller stature, with respect to reproductive and disease competencies, work performance, and cognitive ability. Evidence from studies in humans also shows that food deprivation affects ability to produce healthy babies, physical performance, mental attitude, and disease experience, irrespective of body size. Communities that have evolved under conditions of recurrent scarcity will have developed and accepted what are seen to be the lowest-risk strategies for coping with the immediate and longer-range problems of survival. Because the cost of failure is perceived to be high, there will be pressure against innovation. This tendency to avoid risk-taking, in turn, may be among the grave effects of chronic food deprivation, even when deprivation is not severe.