SYMPOSIUM ON
C0d
Mhifton .~~~~~~~~as
Clinical Nutrition Is a Medical Specialty ROBERT H. HERMAN, MD LOUIS HAGLER, MD San Francisco FEATURED in this issue of THE WESTERN JOURNAL OF MEDICINE is a symposium on clinical nutrition. It should be evident from the content of the symposium that clinical nutrition is a medical spe-
cialty. Clinical nutrition deals with the relation between disease and nutrition. Dietary components can cause acute and chronic illness when deficient, when present in excess or when present in "normal" amounts in susceptible persons who have genetic disease or metabolic conditions, or who are taking certain drugs. Maintenance of a patient's nutritional status is a time-honored ap,proach to the treatment of disease. With the advent of techniques for total parenteral nutrition an increased degree of versatility has been attained for the treatment of conditions which until now had not been amenable to therapy. Despite the recognition that dietary components or their absence can cause illness, that chronically ill patients often are malnourished and that nutritional therapy is technically possible in conditions in which it had been impossible, there still is reluctance by some to accept clinical nutrition as a medical specialty. Instead nutrition is fragmented among other medical specialties where it is used only within the context of that specialty without regard for clinical nutrition as an entity. Part of the problem is due to the early spectacular results in nutrition research and the consequent prevention of nutritional deficiencies. Beginning in the early 1900's vitamins have been Refer to: Herman RH, Hagler L: Clinical nutrition is a medical specialty-Introductory Remarks (Clinical Nutrition Symposium). West J Med 130:93-94, Feb 1979 From Department of Medicine, Letterman Army Institute of Research, San Francisco. The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army or the Department of Defense. Reprint requests to: Robert H. Herman, MD, Chief, Dept. of Medicine, Letterman Army Institute of Research, Presidio of San Francisco, CA 94129
discovered and their mechanisms of action (with a few exceptions) have been adduced. No longer need we fear the specter of vitamin deficiency diseases. The requirements for proteins, essential amino and fatty acids, vitamins and calories have been determined. More recently the requirements for trace minerals have been determined. We can prevent nutritional deficiency diseases, treat them specifically when they do occur, and effect a cure. Nutritional deficiency diseases no longer occur in epidemic form in the United States. The malnutrition that does occur is a consequence of chronic illness, self-neglect, ignorance, or is seen in conjunction with alcoholism or drug addiction. In fact, obesity rather than malnutrition is a major nutritional illness in the United States. The prevention of nutritional deficiency diseases has been so successful and has been so identified with clinical nutrition that clinical nutrition has been relegated to the medical background. In addition, these past accomplishments of clinical nutrition have been overshadowed largely by recent developments in molecular biology, cardiac catheterization, electronic monitoring devices and techniques, surgical transplantation, chemotherapeutic techniques, computerized axial tomography, newer noninvasive diagnostic techniques, radioisotopic methods of diagnosis and treatment, advances in endocrinology and so on; in short, the great achievements of modern medicine. These are great advances of far-reaching consequences for the future. Yet,) by a number of measures-prevention of disease, effectiveness of treatment, relative cost-these latest advances cannot match the past successes of clinical nutrition. No matter how intellectually satisfying, exciting and impressive (and they are impressive) are the recent discoveries in molecular biology (such as DNA biosynthesis, nucleosome structure THE WESTERN JOURNAL OF MEDICINE
93
SYMPOSIUM ON
CNcal Mdddton within chromatin, gene inserts, protein biosynthesis, restriction enzymes, cloning techniques) the immediate application to clinical medicine is limited and costly and in general disease preventon is not yet possible. The newer diagnostic and therapeutic approaches are also limited in application and are expensive. Whenever the fabric of society breaks down as a consequence of a natural catastrophe (flood, drought, storm, earthquake or the like) or some social upheaval (such as war, revolution or economic collapse) the twin evils of nutritional deficiency and infection reappear indicating how vulnerable we are to these age-old afflictions of man. Even in the case of infectious diseases where there have been great triumphs in disease prevention with vaccines and treatment with antibiotics there has been a gradual emergence of antibiotic resistant organisms. Research in clinical nutrition has not stood still. Advances have been made in understanding the mechanisms of action of vitamins A, D, E and K. The biochemical functions of selenium and zinc have been discovered. The role of dietary fiber in the cause and management of disease is being studied intensively. The relationship between dietary lipid and coronary artery disease is gradually yielding to constant inquiry. The role of nutrients as a cause of illness is now better understood. The techniques of total parenteral nutrition have not only enabled us to provide nutritional
94
FEBRUARY 1979 * 130 * 2
support and therapy when enteral feeding is impossible but has forced us to consider what are the total nutritional requirements of man. Major national health problems still exist. We are faced with the widespread occurrence of atherosclerosis in its various manifestations, obesity, diabetes, hypertension, osteoporosis, cancer, alcoholism and its myriad complications, and drug addiction among others. The possible or probable nutritional involvement in coronary artery disease, obesity, diabetes, hypertension, osteoporosis and alcoholism has been investigated extensively. Even the role of dietary components in the pathogenesis of neoplastic disease is under consideration (nitrates, nitrites and nitrosamines, and aflatoxins are examples). How much more effective (in time, effort, money and reduction of distress for the patient) would it be to prevent coronary artery disease and cancer by alterations in diet than to apply diagnostic studies, chronic management or heroic treatment? But, in order to explore the clinical nutritional aspects of these chronic, disabling and lethal diseases we must first recognize clinical nutrition as a medical specialty in its own right. We hope that this symposium on clinical nutrition provides knowledge of some of the recent developments in clinical nutrition and engenders a deeper appreciation of clinical nutrition as a medical specialty.
C0d
Mhifton .~~~~~~~~as
Clinical Nutrition Is a Medical Specialty ROBERT H. HERMAN, MD LOUIS HAGLER, MD San Francisco FEATURED in this issue of THE WESTERN JOURNAL OF MEDICINE is a symposium on clinical nutrition. It should be evident from the content of the symposium that clinical nutrition is a medical spe-
cialty. Clinical nutrition deals with the relation between disease and nutrition. Dietary components can cause acute and chronic illness when deficient, when present in excess or when present in "normal" amounts in susceptible persons who have genetic disease or metabolic conditions, or who are taking certain drugs. Maintenance of a patient's nutritional status is a time-honored ap,proach to the treatment of disease. With the advent of techniques for total parenteral nutrition an increased degree of versatility has been attained for the treatment of conditions which until now had not been amenable to therapy. Despite the recognition that dietary components or their absence can cause illness, that chronically ill patients often are malnourished and that nutritional therapy is technically possible in conditions in which it had been impossible, there still is reluctance by some to accept clinical nutrition as a medical specialty. Instead nutrition is fragmented among other medical specialties where it is used only within the context of that specialty without regard for clinical nutrition as an entity. Part of the problem is due to the early spectacular results in nutrition research and the consequent prevention of nutritional deficiencies. Beginning in the early 1900's vitamins have been Refer to: Herman RH, Hagler L: Clinical nutrition is a medical specialty-Introductory Remarks (Clinical Nutrition Symposium). West J Med 130:93-94, Feb 1979 From Department of Medicine, Letterman Army Institute of Research, San Francisco. The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army or the Department of Defense. Reprint requests to: Robert H. Herman, MD, Chief, Dept. of Medicine, Letterman Army Institute of Research, Presidio of San Francisco, CA 94129
discovered and their mechanisms of action (with a few exceptions) have been adduced. No longer need we fear the specter of vitamin deficiency diseases. The requirements for proteins, essential amino and fatty acids, vitamins and calories have been determined. More recently the requirements for trace minerals have been determined. We can prevent nutritional deficiency diseases, treat them specifically when they do occur, and effect a cure. Nutritional deficiency diseases no longer occur in epidemic form in the United States. The malnutrition that does occur is a consequence of chronic illness, self-neglect, ignorance, or is seen in conjunction with alcoholism or drug addiction. In fact, obesity rather than malnutrition is a major nutritional illness in the United States. The prevention of nutritional deficiency diseases has been so successful and has been so identified with clinical nutrition that clinical nutrition has been relegated to the medical background. In addition, these past accomplishments of clinical nutrition have been overshadowed largely by recent developments in molecular biology, cardiac catheterization, electronic monitoring devices and techniques, surgical transplantation, chemotherapeutic techniques, computerized axial tomography, newer noninvasive diagnostic techniques, radioisotopic methods of diagnosis and treatment, advances in endocrinology and so on; in short, the great achievements of modern medicine. These are great advances of far-reaching consequences for the future. Yet,) by a number of measures-prevention of disease, effectiveness of treatment, relative cost-these latest advances cannot match the past successes of clinical nutrition. No matter how intellectually satisfying, exciting and impressive (and they are impressive) are the recent discoveries in molecular biology (such as DNA biosynthesis, nucleosome structure THE WESTERN JOURNAL OF MEDICINE
93
SYMPOSIUM ON
CNcal Mdddton within chromatin, gene inserts, protein biosynthesis, restriction enzymes, cloning techniques) the immediate application to clinical medicine is limited and costly and in general disease preventon is not yet possible. The newer diagnostic and therapeutic approaches are also limited in application and are expensive. Whenever the fabric of society breaks down as a consequence of a natural catastrophe (flood, drought, storm, earthquake or the like) or some social upheaval (such as war, revolution or economic collapse) the twin evils of nutritional deficiency and infection reappear indicating how vulnerable we are to these age-old afflictions of man. Even in the case of infectious diseases where there have been great triumphs in disease prevention with vaccines and treatment with antibiotics there has been a gradual emergence of antibiotic resistant organisms. Research in clinical nutrition has not stood still. Advances have been made in understanding the mechanisms of action of vitamins A, D, E and K. The biochemical functions of selenium and zinc have been discovered. The role of dietary fiber in the cause and management of disease is being studied intensively. The relationship between dietary lipid and coronary artery disease is gradually yielding to constant inquiry. The role of nutrients as a cause of illness is now better understood. The techniques of total parenteral nutrition have not only enabled us to provide nutritional
94
FEBRUARY 1979 * 130 * 2
support and therapy when enteral feeding is impossible but has forced us to consider what are the total nutritional requirements of man. Major national health problems still exist. We are faced with the widespread occurrence of atherosclerosis in its various manifestations, obesity, diabetes, hypertension, osteoporosis, cancer, alcoholism and its myriad complications, and drug addiction among others. The possible or probable nutritional involvement in coronary artery disease, obesity, diabetes, hypertension, osteoporosis and alcoholism has been investigated extensively. Even the role of dietary components in the pathogenesis of neoplastic disease is under consideration (nitrates, nitrites and nitrosamines, and aflatoxins are examples). How much more effective (in time, effort, money and reduction of distress for the patient) would it be to prevent coronary artery disease and cancer by alterations in diet than to apply diagnostic studies, chronic management or heroic treatment? But, in order to explore the clinical nutritional aspects of these chronic, disabling and lethal diseases we must first recognize clinical nutrition as a medical specialty in its own right. We hope that this symposium on clinical nutrition provides knowledge of some of the recent developments in clinical nutrition and engenders a deeper appreciation of clinical nutrition as a medical specialty.
