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The Relation of Modern Food Science to Nutrition C. G. KING Executive Director, The Nutrition Foundation A major characteristic of science is its tendency to become quantitative. The early stages of progress, however, are gen- erally more imaginative and perhaps more creative, but subse- quent reasoning and applications develop best when guided by the discipline of quantitative data. In this respect, the science of nutrition is no exception. Neither is the science of food. In today's discussion, I want to emphasize certain quantitative aspects of food science in relation to nutrition practices. The Hindu mother sitting in the doorway of her home near Calcutta follows the centuries-old ceremony of massaging her infant with mustard seed oil while the child is held naked on her lap in full sunshine. Before that, she spends hours gathering mustard seed and expressing a small quantity of oil. She has no knowledge of vitamin D, but she is confident that the ceremony is good for the child. Unfortunately she appears to have the same confidence that rubbing a black pigment around the eyes, or wearing a metallic belt, will also keep sickness and bad spirits away. Our North American Indians had a regular practice of gathering fresh root tips from the banks of streams to eat in mid- winter, without having heard of vitamin C. Our own forefathers, in a new environment, lost a great many of their children in sickness and death from rickets, scurvy, and goiter because they had almost no knowledge of the chemical nature or quantitative significance of the nutrients in their food. Even today, there is evidence that many of our own congressmen and other key civic leaders have very limited understanding of quantitative concepts 19
in the biological sciences. But even when they do understand, their freedom to legislate intelligently is circumscribed by the views of the public. This is one of the basic problems in democ- racies, so we have no choice other than to take seriously and patiently our obligation to convey the lessons of science to the public. The efficiency with which our present population is protected in health by an attractive food supply available to everyone, is certainly a major factor in our increased economic strength and in our total potential for cultural progress. There is real value in the concept of nutrition as "the science of foods and their relation to life and health." The goals of nutrition are fundamental too, but far more complicated than is generally appreciated. Stated simply, they are based on practices guided by learning: (a) to identify fully the composition of foods, (b) to find methods of accurately measuring all the nutrients or toxic materials present, (c) to discover the functions of all the nutrients in their respective chemical changes inside the body, and (d) to understand the health relationships of all nutrients at different levels of intake, on a life span basis. There is no escape from the biological implications of the above ideas, but day-to-day living in the best light of each advance in knowledge is far from being automatic. Too many people still have the primitive concept of nutrition as a pleasant meal and a comfortable stomach through the next few hours. Here, where excellent food in great variety is always available, the public can do very well if they are informed about the kinds of food groups that will furnish a balanced diet. How- ever, the food situation is not static. Research progress, new products, changing environments and limited family cooperation all create a constant and serious need for new and reliable information. To be effective the information must be convenient, attractive, interesting, clear, and concise. Without this kind of service the consumers and every segment of the food industry, from farm to grocery store and restaurant, is working against a handicap. 20
Meanwhile, clever but poorly informed, irresponsible and often dishonest propagandists, for their own advantage, confuse and mislead the public and cause both widespread economic waste and sacrifice of health. Nationally organized programs of con- fusion, fear, and falsehood are being conducted by faddists, door-to-door gimmick salesmen, certain unscrupulous "health food" stores, and a considerable number of writers and other artisans in the use of mass-media. So far there has been little restraint on such media through legal or other civic channels, nor has there been an adequate development of honest, effective information to serve the public. There is reason to hope that corrective measures can be developed to meet the public need. Government agencies, the food and related industries, leaders in mass-media of communication, professional organizations, and universities have a responsibility to study the situation carefully and to develop the necessary constructive programs. Until activities of this nature are developed, the public will not have the full benefit of research progress. In the sense of making practical use of our food resources, the population has done reasonably well with its normal pattern of regular meals based on: (a) animal source protein foodsâmeat, milk, fish and poultry products; (b) cereal productsâbreads, biscuits, breakfast foods, and cakes; (c) green and yellow vegetables and root cropsâbroccoli, potatoes, sweet potatoes, tomatoes, turnips, green beans, green peppers, and green peas; (d) fruits, berries, and melonsâoranges, lemons, grapefruit, strawberries, cantaloupe, bananas, peaches, apples, and avocados. Since the educational campaign conducted during the years 1940-45, and the parallel advances in food technology, the classical deficiency diseases such as rickets, scurvy, pellagra, goiter, sprue, and other forms of severe vitamin deficiency have practically disappeared except for individual cases of gross per- sonal neglect. Three large-scale studies in the United States and one in Canada have demonstrated a great improvement from 21
the pre-1940 years; in typical communities (Philadelphia, Nash- ville, Denver, and Toronto) there was no statistically valid dif- ference in the health records of those who had or had not used special dietary supplements in addition to their regular diets. Although anemia is still fairly common, only a small fraction of the cases can be attributed to nutritional causesâthe major factors have been excessive blood loss and other stresses of a non-nutritional nature. When malnutrition had been a factor, the deficiency was usually iron. The public and many educators are only vaguely aware of the built-in protection of nutrients in the present food supply. Much remains to be done, but the trend in furnishing safeguards of nutrients in the general food supply within the pattern of food groups just cited has already shown dramatic results. For example: (a) Iodized salt quickly lowered the incidence of goiter from a major public health problem to a minor one. Increased use of seafoods, largely a result of improvements in tech- nology, gave further benefits in this direction. Introduction of iodate instead of iodide by Dr. Nevin Scrimshaw and his associates proved to be important in areas where re- fined table salt is not available. If all salt were required to be iodized, as recommended by all specialists in this field, there would be still further advantages. These health gains have been made at very low cost and in the opinion of our best medical scientists, without any cases of injury from the practice. (b) Vitamin D standardization of some fluid milk and of nearly all evaporated and dehydrated milk in addition to special infant foods has practically eliminated rickets and related minor deficiencies, at very low costâand without injury. Occasional instances of excessive intake have occurred from the ill-advised independent use of high potency con- centrates. (c) The introduction of various types of enriched, restored, and other forms of standardized cereal products has be- come an important feature of increasing both the quantity 22
and uniformity of consumption of iron, thiamine, niacin, riboflavin. Added milk proteins and scientific blends of cereal and legume protein foods, with or without added amino acids, or possibly fish flour, are of active interest also. (d) Fortunately the margarine manufacturers adopted stand- ardization of their products with vitamin A at an early date. The public has been protected on that score, while the use of margarine has greatly increased. A new trend is under way to include an increased content of polyun- saturated fats containing linoleic acid or its equivalent. (e) Canned foods have been a major factor in making a great variety of stable high quality products available in nearly every home, village, and camp in the United States and Canada. Cooperation with farmers, scientists, and en- gineers has resulted in steady improvements in nutritive quality, safety, costs, flavor, color, and acceptance. By decreasing the overhead space, oxygen tension, and stor- age temperatures, by increasing the rates of heat penetra- tion and cooling, by improvements in biological control, and by systematic checking on nutritive quality in relation to products and processing, the industry has rendered a notable service. One needs to travel or live in parts of the world where this type of industry is not developed to appreciate the value of this kind of progress. (f) More recently, the frozen food industry has also conducted and reported to the public a nationwide study of the nutritive content of frozen foods to establish the value of its products and to serve as a guide to further progress within the industry. (g) The cleaning, chilling, packaging, and refrigeration of fresh fruits and vegetables, and the comparable retail services for meats, poultry, and seafoods have been important factors in conserving both their nutritive quality and their public acceptance in local and distant markets. In terms of research and education, I want to emphasize the point that all materials in our food, whether classed as essential, 23
nonessential, or toxic, should be evaluated nutritionally in terms of three zones or ranges in quantity. (a) In the lowest zone quantitatively, no significant biological effect is observed. (b) In a second, higher zone, biological effects will be evident, and they may be either favorable or unfavorable. If favor- able, a part of the task is to find the approximate quantita- tive range that is optimum and desirable. (c) A third, higher zone will then be found where there is clear statistical evidence of injury irrespective of the effect at lower quantities of intake. Initial clear signs of injury, however, are nearly always progressive with increased quantities. Complete data of this kind may require much research, but in practice, this kind of approach applies equally well to essential nutrients, nonessential nutrients, and materials that are com- monly regarded as toxic or poisonous. Evaluation of food addi- tives and residues can be interpreted on the same basis. After an initial range of practical values has been established, further research is generally required to assess the effects of varying quantities of other nutrients. Both in agriculture and in human nutrition, many recent relationships of this nature have been dramatic, as illustrated by the wide zones of overlapping functions of selenium and vitamin E, copper and molybdenum, choline and methionine, or niacin and tryptophan. The urgent need for the above quantitative kind of approach in evaluating food constituents can be illustrated also in terms of the last eight "trace" or micronutrients found to be essential for optimum health. Copper, zinc, manganese, fluorine, cobalt, molybdenum, selenium, and chromium were all studied bio- logically through several decades or centuries because they were definitely toxic. The last two were also regarded by some ob- servers as carcinogens (causing cancer). Thus each of these ele- ments, now identified as an "essential nutrient" in the second or intermediate quantitative zone indicated above, takes its signifi- cance only on a quantitative basis. In very minute quantities, they are biologically insignificant. At a higher level they ap- parently occur in all living plant and animal cells and in all native 24
soils and water supplies. They all show a range of optimum nutritive value. Then in a third higher zone, they can be de- scribed as "poisons". The tendency for all living things to be much alike in chemical composition serves as a reasonably good but not fully adequate safety factor. A variety of foods tends to develop a good average effect. (For the past three decades, 1930 to 1960, a new micronutrient has been discovered, on the average, nearly every year.) The need for lay as well as professional personnel to recognize the validity of this quantitative viewpoint in regard to food con- stituents is equally important in food production, in education, in establishing regulatory policies, and in formulating advertising claims. With respect to the immediate problems facing the public and the food industry, the above point is illustrated in the three fields of food and nutrition research that are now most active. In the technologically advanced countries intense effort is being made to establish requirements for an ideal intake of fats in human diets. This problem is tied closely with efforts to conserve health, particularly in the upper age brackets. Despite the complexity of the problem and the life-span type of timing for the human and animal studies, new techniques of quantitative study are making it possible to progress fairly rapidly. Food scientists in industry are alert to making use of each quantitative type of new information in relation to new products such as shortening, salad oils, and margarine. Closely akin to the problem of exact fat composition is the search to discover to what degree genetic trends and the intake of specific minerals, sugars, vitamins, proteins, and total calories can affect the observed changes in fat deposition, blood clotting, hardening of the arteries, and glandular functions. In stark contrast to our problem of excess calories (and per- haps an excess of "rich foods") in proportion to physical work output in the technically advanced countries, the underdeveloped countries face one of their most severe health, social, and eco- nomic problems in the rampant deficiency of good quality protein foods. Accelerated progress in this field is likely to have an im- portant bearing on the prospect for peace in each of these 25
countries and in the world at large. The penalty from protein deficiency is particularly heavy on the health of infants and small children in the approximate age range of six months to four years. In view of Dr. Scrimshaw's discussion of this subject later in the program, I will only comment on two of the related points. First, the advances in this field of activity, both medically and in food technology, are greatly aided by new, rapid, and accurate micromethods of quantitative analysis. Second, a very great practical advantage is now evident from earlier basic studies such as those of Professor W. C. Rose in establishing the identity and quantitative requirements for amino acids in rats and in men, and the related work of Professors C. A. Elvehjem, Grace A. Goldsmith, W. J. Darby, and others, in identifying the bio- logical balances between certain specific amino acids, vitamins, fats, and minerals. Similarly, the fundamental work of Professors A. L. Lehninger, Konrad Bloch, Fritz Lipmann, E. P. Kennedy, Carl Cori, and others in discovering the pathways by which the glyceride fats and cholesterol-type products are formed and in part are used for energy now furnishes many of the best guides in attacking the problems of relating food practices to health. In summary: (1) Supplying generous and balanced quantities of all the nutrients known to be required for human growth and health in a great variety of attractive, stable, convenient, low-cost, and commonly used foods is now a well established practice in the United States, Canada, Western Europe, and other technically advanced areas of the world. (2) This fortunate situation does not decrease the need for continued emphasis on increasing research and education. The outlook for good dividends from intensive research and educa- tion is brighter now than ever before. They will serve well in the face of rising population pressures, precautions against the risks of war, needs for increased efficiency in protecting health, and in the crucial competitive need for strengthening the con- structive economic and social forces in all parts of the world. (3) The first requirement for meeting successfully the situa- tions that lie ahead will certainly be for competent and 26
adequately trained personnel with a high sense of social responsi- bility. No other asset is quite so urgent. (4) The growing interdependence of men in different fields of science, in different types of industry, and in different areas of civic responsibility, stands out more clearly now than ever before. Our faith in democratic forms of society demands that we share more actively in carrying this kind of understanding to the public. Voting and eating are close relatives in a very large family. 27
