CRC Nutritional Aspects of Aging II. [antikvár]

PREFACE The phenomena of aging are so obvious that most of us assume that we know what the term means. However, one will be surprised to find that people have a hard lime agreeing on an objective scientific definition of aging. The aging process involves progressive changes with age after maturity in various organs leading to decreased functional ability. It reflects changes in many molecular, cellular, and systemic processes that take place with time. Often, aging is associated with chronic diseases although aging itself is not a disease. Proper nutrition throughout the life span is of importance in maintaining mental and physical health. We believe that nutrition in early and middle life may have an important impact in determining the rate of aging. Therefore, the study of nutrition and aging, especially the study of nutrition and life span, cannot exclude nutrition at early life and middle years. In addition, some nutrition-related diseases which occur more frequently in later years may be prevented by adequate nutrition or can be managed by nutrition intervention. Nutrition is one of the environmental factors influencing biological aging which can be controlled. Although we should deal with biological age rather than chronological age in gerontology, it is not easy to define biological age due to the lack of clear measures of biological age. The elderiy, or the aged, are generally accepted as people who are at or after retirement age which is usually 65. As far as the Title Illb National Nutrition Program for Older Americans is concerned, people at age 60 or above are qualified to participate. The number and the proportion of the elderiy population in the U.S. are increasing rapidly. The Bureau of the Census reported that in 1977 there were 23 million people over 65 years of age which was about 10.6% of the total population. It is predicted that by the year 2050 there may be about 30 million people or 20% of the total U.S. population over the age of 65. The life expectancy at birth in 1977 was 76.5 years for women and 68.7 years for men, whereas the life expectancy at birth in the year 2050 is predicted to be 81 years for women and 71.8 years for men. With increasing life expectancy and increasing size of the elderiy population, the quality of later life is of concern. The elderiy have special health requirements but their socioeconomic status often produces difficulties for them to meet these requirements; thus they are at increasing risk of health problems. Nutritional inadequacy and the role of diet in pathogenesis of diseases are important components in health care of the elderly. The health care of the elderiy is not limited to the treatment of diseases but also includes the prevention of diseases. The need for information on nutrition and aging is increasing. The first section in Volume I describes the fundamentals of nutrition and aging which include research strategies for the study of nutrition and aging. The nutritional modulation of the aging process which has provided a major breakthrough in the field of nutrition and longevity is also discussed. In the second section, factors affecting the nutritional status of the elderly are discussed. These include biomedical influences, and social and psychological aspects. Section 3 includes dietary characteristics of the elderiy population and methods for the assessment of nutritional status. The nutritional status of the elderiy with respect to individual nutrients as determined by dietary survey and by biochemical methods is described Section 4. Section 4 also includes discussion on nutrient metabolism, requirements. in nutritional imbalances, and deficiencies of nutrients. Energy metabolism and obesity as a factor in pathogenesis of diseases are also discussed. In the first section of Volume 11, toxicological factors affecting nutritional status are discussed. Medications and alcohol may affect nutritional status. Section 2 provides a discussion of nutrition-related diseases which occur more frequently among the elderiy. Cardiovascular diseases including coronary heart disease and cerebrovascular disease are the leading causes of death in the U.S. The relative importance of cardiovascular diseases, in terms of all deaths for the given age group, rises steadily with age. The death rate from these diseases is 28% for the middle age group (age 35 to 44), and is 69% for the old age