Overview of nutritional status in the United States.

Nutritional surveys attempt to estimate the nutritional status of people from various physical (clinical, anthropometric) and biochemical (with respect to nutrients) measurements, whereas dietary surveys attempt to measure what people eat. Although dietary surveys help explain possible reasons for clinical and laboratory findings, the nutritional status of people cannot be inferred from the diet alone. The determinants of nutritional status and, for that matter, the health of the individual and the population as a whole, include a variety of factors, biologic (genetic), behavioral, sociocultural, economic, and environmental. Diet is one environmental factor of great importance in determining man's level of health and well-being. The 1971-1974 HANES showed that excessive weight or obesity is a major health problem affecting people at all age and economic levels. At the same time, the survey showed a trend toward low calorie intake among certain adults over age 45, particularly women over age 60. The data also indicate that iron deficiency occurs among young children, pregnant women, and the elderly and that dental caries is a prevalent condition. Vitamin and iodine deficiencies, for practical purposes, do not exist in the U.S. population, although several surveys have uncovered certain vitamin deficiencies among the elderly. Dietary deficiencies, where they occur, are related to socioeconomic and cultural factors, specific conditions, and disease states. Reliable data do not exist to estimate the extent of malnutrition among the hospitalized and institutionalized population.