National Academies Press: OpenBook
« Previous: Constraints on U.S. Agricultural Production and Research: Federal Regulations and Legislation
Suggested Citation:"Human Nutrition." National Research Council. 1975. World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and. Washington, DC: The National Academies Press. doi: 10.17226/18644.
×
Page 55
Suggested Citation:"Human Nutrition." National Research Council. 1975. World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and. Washington, DC: The National Academies Press. doi: 10.17226/18644.
×
Page 56
Suggested Citation:"Human Nutrition." National Research Council. 1975. World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and. Washington, DC: The National Academies Press. doi: 10.17226/18644.
×
Page 57
Suggested Citation:"Human Nutrition." National Research Council. 1975. World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and. Washington, DC: The National Academies Press. doi: 10.17226/18644.
×
Page 58
Suggested Citation:"Human Nutrition." National Research Council. 1975. World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and. Washington, DC: The National Academies Press. doi: 10.17226/18644.
×
Page 59
Suggested Citation:"Human Nutrition." National Research Council. 1975. World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and. Washington, DC: The National Academies Press. doi: 10.17226/18644.
×
Page 60
Suggested Citation:"Human Nutrition." National Research Council. 1975. World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and. Washington, DC: The National Academies Press. doi: 10.17226/18644.
×
Page 61
Suggested Citation:"Human Nutrition." National Research Council. 1975. World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and. Washington, DC: The National Academies Press. doi: 10.17226/18644.
×
Page 62
Suggested Citation:"Human Nutrition." National Research Council. 1975. World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and. Washington, DC: The National Academies Press. doi: 10.17226/18644.
×
Page 63
Suggested Citation:"Human Nutrition." National Research Council. 1975. World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and. Washington, DC: The National Academies Press. doi: 10.17226/18644.
×
Page 64

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

SECTION J: HUMAN NUTRITION INTRODUCTION Providing adequate nutrition for people is the basic purpose of food production. People need nutrients for their physiological well-being, and to meet this need they consume food. The difficulty frequently experienced in under- standing and resolving nutritional problems involves this relationship. Agricultural production provides, for most of the world's cultures, the foods which are the carriers of the essential nutrients. The amount and variety of food that is available, its cost, acceptability, and nutrient composition determine the ability of individuals and a population as a whole to fill their nutritional needs. As we contemplate changes in food production to provide better nutrients for people, it is important to consider the influence of food preferences and eating habits on the actual intake of nutrients. The nutritional status of individuals and populations may be revealed in a variety of ways. Acute disease may result in humans directly from nutritional deficiencies, particularly during periods of food shortage. Chronic deficiencies, frequently characterized by poor growth and development, may also exist where the specific nutritional deficiency is not well defined. Excesses of particular nutrients may also cause chronic or less commonly acute diseases. Knowledge of nutrient requirements and their interrelationships under the varied environments of human existence is of fundamental importance. There is also a need for improving our ability to transfer information concerning nutritional needs to the foods people consume, and conversely to evaluate nutritional status from information about the food consumed by individuals and populations. There is a need for evaluating in a cost- effective manner the nutritional status of human populations. With this information—knowledge of food consumption and food composition—it will be possible to assess more adequately the nutritional status of individuals and populations and to develop programs to maintain or improve their status. Greatly increased support for research on nutrition and food science is needed to determine the nutrient require- ments, nutritional status, and food consumption patterns of people as well as the nutrient composition of raw foods, the effects of food processing, storage, and preparation and the cost—in energy and materials—of alternative ways to -55-

improve the nutritional status of populations. The following chapter discusses specific recommendations concerning such research. -56-

CHAPTER 6 NUTRITION RESEARCH RECOMMENDATIONS 1: Nutrition Survei1lance. Efficient and inexpensive methods are required for determining the nutritional status of individuals and populations. 2: Food Consumption. Since people require nutrients but eat foods, it is essential that proper methodologies be developed to determine what individuals and populations eat and what factors influence their choices. 3: Food Composition. To translate food consumption to nutrient intake it is essential to have accurate and timely information on the nutrient composition of foods, compiled in a manner that permits continued updating and rapid retrieval. Continued development of this capability is an essential part of a national nutrition program. 4: Nutrient Requirements of Man. Research is critically needed to more accurately define the nutrient requirements of man and those factors in his environ- ment that interact with or influence the need for essential nutrients. 5: Food Intervention. Methods should be developed to evaluate the potential impact of intervention programs on the nutritional status of the target group so that the cost-effectiveness of the program can be evaluated on a timely basis. 6: Constraints. Various factors that potentially contribute to the problem of improper nutrition in the U.S. should be analyzed to determine the major constraints involved. -57-

NUTRITION SURVEILLANCE Rationale A prerequisite for the introduction of intervention programs to improve the nutritional well-being of a popula- tion is sound knowledge of the magnitude and extent of nutritional deficiencies by geographical areas, income levels, age groups, and other identifiable segments. A properly designed nutrition survey can provide this base line information and guide programs designed to alleviate the particular nutritional problem identified, such as protein calorie malnutrition, iron deficiency, or vitamin A deficiency. Repetition of the nutritional surveillance at predetermined intervals is essential to assess the impact of an intervention program that has been instituted. It is particularly important that surveillance be maintained on vulnerable groups in society, such as children or lactating mothers. Properly fashioned, these surveys can provide an early warning system to alert governments to potential nutritional problem areas and prevent problems from evolving into disasters. To be most useful, methodologies for determining nutri- tional status must be reliable, efficient, inexpensive, readily implemented, and capable of being carried out by nonprofessional but well-trained personnel. Methods for assessing nutritional status in use today range from simple anthropometric measurements to elaborate use of clinical measurements as in the Interdepartmental Committee on Nutrition for National Defense (ICNND) surveys. We need a careful evaluation of existing techniques and development of a uniform methodology that can provide accurate and comparable nutrition information on a worldwide basis. Whatever methodologies are used, it is essential that the measurements reveal accurately the nutritional status of the individual and/or population group surveyed. FOOD CONSUMPTION Rationale Since people require nutrients but eat foods to obtain these nutrients, it is essential that we have sound information on what people eat. A course of action to meet food production and nutrition needs must be based on the composition of the foods that are consumed. It is urgent that we get this information now to guide other facets of an overall food and nutrition program. Food consumption practices differ among individuals and among different income and population groups. To plan for the nutrient food needs of those individuals or groups -58-

potentially at nutritional risk, information must be developed on the types and amounts of food consumed. Continued surveillance of food consumption habits will describe the current food intake and, over time, will alert agencies to changes in food consumption that may be altering nutritional status. The food consumption practices of the infant, the pregnant and lactating woman, and the rapidly growing adolescent must be known if malnutrition or other health problems related to nutrition are to be avoided, or if effective food intervention programs are to be mounted. For other population groups beyond the so-called "target groups," however, food consumption surveillance may also be needed since diet has clear implications for serious health problems, such as heart disease, goiter, and anemia. Research is needed on the development of less expensive methodology for deriving information on the safety of foods. Food contaminants or microbiological metabolites may pose hazards to particular population groups consuming large amounts of a suspect food. Some food additives when consumed excessively may create risk of toxicity or interfere with the consumer's benefit from certain key nutrients. Numerous food intervention programs are now being funded by Congress but little or no data is being accumulated on how these programs are influencing food consumption or nutritional status. FOOD COMPOSITION Rationale To interpret the nutritional significance of food consumption patterns, diets need to be analyzed for the variety and quantity of nutrients they contain. The biological or metabolic usefulness of the form of the particular nutrient as it exists in a food must be known, since some nutrients in certain foods may be relatively unavailable for use by man. The many steps that a food must go through from production to consumer may have marked effects on the ultimate nutrient composition of the diet. Current programs in nutritional labeling of foods require that this knowledge be generated. Up-to-date reference tables on the nutrient composition of foods as consumed are needed for the various regions and nations of the world. As new food products are developed and accepted into the diet, data about their nutrient composition must be compiled. Losses and wastage that may be encountered in transportation, storage, processing, and preparation also need to be known. Breeding programs oriented toward nutritionally improved varieties of food crops must be based on knowledge -59-

of the nutrient composition of foods and of natural toxicants and the genetic reservoir that is available. Breeding for nutritional improvement should also be related to the significance of the food crop as an economic source of key nutrients in the diet. Production practices need to be monitored for their implications for nutrient composition, since both improvement and reduction of such nutrients as protein and various mineral elements are known to be possible with alteration of some production practices. Research programs to meet our various needs for data on food composition should be undertaken to guide our actions and commitments during the years ahead. NUTRIENT REQUIREMENTS OF MAN Rationale The requirement of man for essential nutrients is the basis for establishing recommended levels of nutrient intake. The knowledge base for determination of recommended dietary allowances is surprisingly weak. To a considerable degree, the values for nutrient allowances currently used represent extrapolations to all ages from limited studies of healthy young adults. The numbers studied have generally been too small to provide a reasonable estimate of individual variation even for healthy young adults, and they make no adequate allowance for the special needs of individuals subject to stress from numerous factors of environment or disease, such as parasitic and other acute and chronic infections, extremes of temperature, activity, and such losses of essential nutrients as may occur through sweat from heavy physical work or high environmental temperatures. There is an acute need for centers of nutrition research for evaluating the nutrient requirements of the healthy man. Emphasis should be placed, not only on societies prone to undernutrition, but also on the highly developed industrial society where qualitative changes related to sources of calories in the diet and general overconsumption can lead to widespread morbidity and mortality, as seen in heart disease, obesity, and similar conditions. Emphasis should be placed on defining the minimum and optimum nutrient requirements for growth, pregnancy, and lactation in healthy and stressful situations, and on nutrient interactions and the effects of nutrient excesses. Nutrient requirements must be defined and translated into terms that permit their use by those concerned with the food supply as well as those concerned with the health care of people. -60-

FOOD INTERVENTION Rationale Food intervention programs should be designed to improve the nutritional status of the target population. Effective programs will be the outgrowth of data obtained from nutritional surveillance studies which have identified a potential nutritional risk to the target group. In addition, information concerning the food habits and food consumption patterns of the target group and factors which have an impact on the target group's behavior should be part of the analysis concerning the proposed method of intervention. Several methods of nutritional intervention are in use today. Programs on food fortification, nutritional labeling, nutrition education, and supplemental feeding (such as food stamps, surplus food distribution, school lunches, and women and infant children feeding) are now being funded in excess of $6 billion annually. Little or no effective evaluation of the impact of these programs on the nutritional well-being of the target groups has been carried out. The cost-effectiveness of these programs versus other means of expanding purchasing power has not been evaluated for their relative impact on nutritional goals. As a consequence there is little information with which to assess the continuing value of these programs. The development of effective technology in areas of nutritional surveillance, food consumption, and food composition is a prerequisite to developing accurate evaluations of intervention programs. Similar considerations apply to international food aid programs carried out by the U.S., the European countries, and other developed countries. Little if any evaluation has been made of the nutritional impact on populations in developing countries. Effective evaluation should be a built-in requirement of nutritional intervention programs. While many programs today specify that evaluations should be made, the support has not been provided for developing the necessary technology and for integrating the evaluation of the many current intervention programs. Are currently authorized food fortification programs effective? Should standards of identity or other regulations be changed to permit broader fortification of products which are significant sources of nutrients in the diet? Answers to these questions should guide government policies in food fortification programs. Nutrition education programs today are fragmented and appear for the most part to be ineffective. Little effort has been devoted to determining the most effective period in the education of the individual to introduce sound nutritional concepts. Is this best done at preschool or elementary levels, or later in the educational cycle? What kind of training is required for nutrition education -61-

personnel? Before we can expect improvement in people's understanding of what constitutes sound nutrition, it is necessary to know more about effective educational intervention. How effective in improving the nutritional standard of the recipients are food stamp and other food supplement programs or the international food aid programs? This information is woefully lacking. We may, in fact, find that current eligibility requirements or other factors are not properly established. Do these programs really provide nutritional benefits, or are they merely programs for income supplementation, with only random impact on the nutritional health of the individual? Technology for proper evaluation of these programs must be developed so that policy makers can use it in choosing between true nutritional supplementation and income support. CONSTRAINTS Rationale Many factors have contributed to the persistence of malnutrition in the U.S., and constraints on the goal of abolishing malnutrition in the developing countries of the world are formidable. In both cases, malnutrition is most often due to maldistribution of existing food supplies, although famines continue to occur in limited populations due to local or regional crop failures. Inadequate purchasing power of low-income groups and inadequate knowledge of the essentials of a good diet are the limitations most often cited, but these in turn reflect economic and social policies which are not easily altered. Some specific constraints are discussed below. 1. Lack of education and training in nutrition In the U.S., physicians, dentists, and other medical and public health workers, school teachers, and the general public receive little or no specific education or training in nutrition, and this pattern is replicated in the developing countries. At present nutrition information is most often provided by advertising and other commercial activities and oriented to the promotion of specific products or classes of products. Lack of knowledge as to the most effective period in a person' s educational cycle to provide nutritional information and the qualifications of personnel required to provide this input represent a major constraint on our ability to make desired progress in the nutritional literacy of people. -62-

2. Lack of opportunity for economic progress In most developing countries, the lower soci©economic groups are at an extreme disadvantage and often see little hope of economic progress. In the U.S., malnutrition still occurs most commonly among underprivileged groups, such as migrant laborers, American Indians, Chicanes, and urban blacks. 3. Lack of economic support Federal and state support of nutrition education, training, and research is meager, and funds for adequate nutritional and dietary surveys on a national scale for nutrient surveillance have simply not been forthcoming. The USDA should have a strong intramural and extramural program in human nutrition. At present, only minor resources are allocated to this purpose. Research on food composition, the effects of food processing, and food safety are similarly grossly undersupported. While many current intervention programs require evaluation, support for the necessary technology to effectively accomplish this and to integrate the evaluation of the many supplemental programs now established is wholly inadequate. 4. Government policies In the U.S., at local, state, or national levels, policy decisions are often made which have unrecognized or disregarded repercussions for human nutrition, and in developing countries nutritional considerations seldom enter into policy planning although food and nutrition can be shown to be essential aspects of national, social, and economic development. For example, the sometimes arbitrary and inconsistent eligibility standards that may be established by the various governmental agencies involved for participation in supplemental food programs often result in denial of support to those in real need. Similarly, priority should be given to the production of legumes, which are an essential supplemental part of the the diet of lower income people of the country, rather than to artificial support of the price of a basic crop like rice or sugar, where the net result would be a poorer diet. In other instances environmental or safety regulations may require large expenditures of money for arbitrary levels of compliance where benefit relative to risk is minimal. The concept of zero tolerances for many chemicals places regulations on the basis of chemical analysis rather than on evaluation of potential risks versus benefits. -63-

5. Political considerations Much can be done to improve nutritional status where the political interest or will exists to do so. Conversely, decisions are often made for political reasons which have adverse repercussions on nutritional status. These may range from overly large foreign purchases or exports which raise domestic retail prices to ineffective and costly intervention programs continued for political reasons. Frequently artificial price supports for production of crops for export will generate foreign exchange without considering its impact on the diet of lower socioeconomic groups in the population. We need more analysis of and information about the trade-offs between production of food for domestic consumption and for export to enable decision makers to make regional agriculture policy decisions. Food stamp eligibility rules may be changed to permit broader participation as a means of increasing effective income, not as a means of necessarily improving nutritional status. Once implemented, such programs are hard to change because of the political pressures associated with them. 6. Regulatory policies Regulating agencies often set up unnecessary barriers to the development of more nutritious or lower cost foods because of their novelty, competition with traditional sources, culturally biased aesthetic judgments, techno- logically outmoded standards of identity, or simply failure to change anachronistic rulings to allow for advances in nutrition, food science, and technology. Standards of identity for many foods are difficult to change even though improved nutritional content may result. The development of a high-protein macaroni, filled milks, restrictions on margarine which existed for years in many jurisdictions, and vitamin C fortification of fruit juices under standards of identity as a means of standardizing vitamin content are representative examples. A carefully stated food and nutrition policy could provide a framework within which many of these constraints could be evaluated and, it is hoped, eliminated. -64-

Next: Natural Resources Base, Input Management, and the Environment »
World Food and Nutrition Study: Enhancement of Food Production for the United States : a Report of the Board on Agriculture and Renewable Resources, Commission on Natural Resources, National Research Council, Prepared for the NRC Study on World Food and Get This Book
×
MyNAP members save 10% online.
Login or Register to save!
Download Free PDF
  1. ×

    Welcome to OpenBook!

    You're looking at OpenBook, NAP.edu's online reading room since 1999. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website.

    Do you want to take a quick tour of the OpenBook's features?

    No Thanks Take a Tour »
  2. ×

    Show this book's table of contents, where you can jump to any chapter by name.

    « Back Next »
  3. ×

    ...or use these buttons to go back to the previous chapter or skip to the next one.

    « Back Next »
  4. ×

    Jump up to the previous page or down to the next one. Also, you can type in a page number and press Enter to go directly to that page in the book.

    « Back Next »
  5. ×

    To search the entire text of this book, type in your search term here and press Enter.

    « Back Next »
  6. ×

    Share a link to this book page on your preferred social network or via email.

    « Back Next »
  7. ×

    View our suggested citation for this chapter.

    « Back Next »
  8. ×

    Ready to take your reading offline? Click here to buy this book in print or download it as a free PDF, if available.

    « Back Next »
Stay Connected!