Body weight, health, and longevity

In the United States, the weight associated with the greatest longevity tends to below the average weight of the population under consideration, if such weights are not associated with a history of significant medical impairment. Overweight persons tend to die sooner than average-weight persons, especially those who are overweight at younger ages. The effect of being overweight on mortality is delayed and may not be seen in short-term studies. Cigarette smoking is a potential confounder of the relationship between obesity and mortality. Studies on body weight, morbidity, and mortality must be interpreted with careful attention to the definitions of obesity or relative weight used, preexisting morbid conditions, the length of follow-up, and confounders in the analysis. The terminology of body weight standards should be defined more precisely and cited appropriately. An appropriate database relating body weight by sex, age, and possibly frame size to morbidity and mortality should be developed to permit the preparation of reference tables for defining the desirable range of body weight based on morbidity and mortality statistics.

The role of the federal government in research on nutrition and aging

As the population of the elderly will increase 10% within the next 50 years, research on the health problems affecting them becomes pertinent. The major agency supporting biomedical and behavioral aspects of nutrition research and training is the National Institutes of Health. The research it carries out is through grants and contracts, and through a new National Program in the Clinical Nutrition Research Unit. Additional research on nutrition for the aging is performed by the US Department of Agriculture at the Tufts University Human Nutrition Research Center on Aging. The coordination of nutrition research and training at the federal level is accomplished through the Joint Subcommittee for Human Nutrition Research operating out of the Executive Office of the President.

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.

The scientific basis of the "Goals": what can be done now?

Universal dietary goals for the general public cannot be formulated or implented. More appropriate would be guidelines to serve as preventive measures for specific groups, based on genetic endowment, age, sex, and condition. Nutrition education as a component in health education is essential.

Growth characteristics in patients with Bartter's syndrome

Studies on the growth and development of patients with Bartter's syndrome indicate that severe growth retardation occurs during infancy and early childhood. Delayed adolescent growth spurt has occurred in all patients studied thus far who had manifested the syndrome during infancy. Normal stature is eventually attained. Mental development ranges from normal to brain damage and dysfunction; however, the majority of patients show some degree of mental retardation. The coexistence of Leigh's encephalopathy with Bartter's syndrome in one patient and the finding of severe motor and congnitive retardation with communicating hydrocephalus in another indicate that the prognosis of mental development in some cases of Bartter's syndrome is guarded. Particular attention should be given to maintaining normal nutritional status in all patients, particularly during infancy and early childhood.