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EMERGING PRIORITIES FOR THE NUTRITIONAL SCIENCES J. C. Waterlow There will be no nutritional science, and hence no useful discussion of priorities, unless there is a continuing flow of young people into the study of the subject. What challenges face them? They will find a degree of polarization among people working in nutrition (Waterlow, 1981~. It is a commonplace that malnutrition results from poverty. Here are two quotations from the same number of the United Nations University (UNU) Food and Nutrition Bulletin: On . . . the use of external bilateral and multilateral instruments to build a global economic order of significantly greater equity (within as well as among countries), I am rather pessimistic, at least as far into the next 15 to 20 years as I can see (Joseph, 1985~. It Is realistic to contemplate the elimination of hunger and malnutrition if and when governments adopt social, economic, agricultural, educational, and health policies that have enabled countries with a wide range of political systems to achieve this goal in a surprisingly short time. . . . The encouragement and assistance that international, bilateral, and voluntary agencies can provide will make a critical difference (Scrimshaw, 1985~. We note in passing that Scrimshaw did not include nutrition in his list. Those statements and reflections were presumably addressed to governments and other organizations. However, at the end of the road, whatever is achieved depends on people. What should a young person do who wants to make a contribution? Grant told us at the International Congress of Nutrition in San Diego 4 years ago that we have to stimulate political will. That advice was, I suppose, given to us as citizens, not as nutritionists. In this climate of opinion, many people feel that their best contribution is through the social sciences, management, administration, and so forth. It is not unnatural that the biomedical scientists should feel on the defensive. What can we contribute, other than to act as a conscience for governments, as 43 -
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44 Gopalan of India put it at the World Health Assembly some years ago. If the biomedical scientists are on the defensive, it is partly our own fault. In the United States and United Kingdom, nutritional science has gained much of its strength from animal husbandry, as is obvious if we look at the institutions in these countries and the traditional nutritional journals. I do not think it would be unfair to say that perhaps the greater part of scientific output in nutrition is irrelevant to Third World problems. That is natural enough, as long as most ~ ~ ~ _ ~ ~ 1 __ _ ~ ~ nutritional science Is done In developed countries. It might be supposed that the way to build a bridge between the social and biomedical components of nutrition is by multidisciplinary discussions, as in this sympo- sium. However, I like very much a phrase in Galbraith's autobiography: ''Discussion is a vacuum designed to fill a vacuum" (Galbraith, 1982~. We get a smattering of each other's point of view, but that is no substitute for a proper basic training. Richard Jolly, in his address at the last International Congress of Nutrition (in press), spoke of the importance that Barbara Ward attached to professionalism. I fully agree. There is no subject in which professionalism is more needed than in nutrition. In what other subject would you find that, of all the professors and writers, including me, so few have had any basic training in what they profess? In what university, for example, can one find a proper degree course in developmental nutrition--equivalent, say, to a degree in agricultural economics? I will not enlarge further on . . . tne SUbJ ect or training, except to say that, if I had control of a great deal of money, I would give priority to establishing such university departments in Third World countries or strengthening them where they exist. It is sad that national and international agencies, with few exceptions, seem to find great difficulty in pro- viding long-term institutional support in developing countries (United Nations University, 1984~. At the same time, we all say that a major bottleneck in long-term measures for the prevention of famine is the lack of local infrastructure and technical know-how. Is there not some hypocrisy here? Let me now come somewhat closer to my title: priorities for nutritional sciences. In defining priorities, the scientist needs some guidance from
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45 policy-makers and planners on the general framework within which he is to operate. Is the aim of policy to improve the nutritional state of virtually the whole population in poor countries? Or is it to eliminate the severe cases? I have not seen the distinction thoroughly discussed in relation to nutrition and malnutrition, and certainly not with the passion that surrounds the contro- versy over high blood pressure--whether to try to shift the distribution of blood pressure in the population as a whole or to concentrate resources on those who are clearly at risk. For nutrition, the two policies can be promoted together, and they are coming closer together. The ''trickle-down" approach through overall economic development seems to be losing ground in favor of the "basic-needs" approach (Streeten et al., 1981) or ''development with a human face" (Jolly, in press). The emphasis has changed over the years; there is now much talk of community participation and of increasing the social mobility of women (Joseph, 1985~. Be that as it may, such policies are largely in the province of social scientists, economists, and politicians. The second approach--what Streeten et al. (1981), using a military analogy, called "precision bombing"-- lies squarely in the province of the health sector. Such a strategy might well be unpopular in the present cli- mate, because it goes against the principle of prevention for all and is reminiscent of the out-of-fashion hospital approach. Nevertheless, opinion does seem to be moving in that direction, as judged by a recent World Bank paper (Lipton, 1983~. The practical difficulties are enormous, but I believe that they can be overcome through the primary health care system, if it is properly geared to that strategy. Moreover, I think that such a strategy will have a "trickle-up" effect. Is it not the case that, whatever the causal mechanism, birth rates tend to decrease as infant mortality falls? I referred to "severe cases," and it is precisely the problem of defining "severe" that should indicate the priority for nutritional sciences in the next decade. The difficulty, of course, is that nutritional status is a continuous variable, so it is artificial to draw a line between those who should and those who should not be called severely malnourished. Nevertheless, in real life
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46 it has to be done. The analogy with blood pressure applies here also: the doctor, confronted with this continuous variable, has to decide on the level that warrants treatment. In Britain, we have just finished a very large trial of the effects of lowering the cutoff point of blood pressure for antihypertension treatment: It appears that the gains are small in relation to the enormous cost of hypotensive drugs. Thus, the choice of where to place the cutoff point depends on two things: biological knowledge (how the risks vary in degree and kind as one moves down the ladder of worsening nutri- tional state) and practical considerations (such as the size of the group at risk, how it can be reached, and the resources needed to deal with it). For nutritional research on all problems, the same general question applies: how best to match resources and results. However, the different problems are in differ- ent stages of development. In the case of vitamin A deficiency, iodine deficiency diseases, and anemia, there is a great body of knowledge, although, of course, it is never complete and there have been some exciting scien- tific developments in recent years. Interest in these conditions is high, and we have the technology for pre- vention. I judge that it is largely a matter of resources and sometimes of political will. It is remarkable, for example, that in southern Germany 30% of women still have goiter (Elton, 1978~. Scientific knowledge of other conditions is more or less in its infancy, and we do not even know how important they are. Examples are trace-element deficiencies and the effects of mycotoxins. There is also protein-energy malnutri- tion. The magnitude of the problem of malnutrition is enormous; there is a great deal of knowledge, but it has serious gaps. Until those gaps are filled, we cannot have a rational policy for prevention. I shall now discuss three examples of gaps in our knowledge on the effects of energy and protein deficiency that I think should have a high priority for nutritional science in the next decade. Protein takes second place to energy, because, as is widely accepted, an intake that provides enough energy will usually supply enough protein. There are important exceptions, but those concerned with policy, such as the Food and Agriculture Organization (FAG) and the World Bank, are surely right
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47 to concentrate first on energy intake. The three subjects deserving priority are body size, adaptation, and resistance to infection. BODY SIZE . The best way of coping with a deficit in energy intake, is to be small. But how small? To normalize for differences in height in adults, it is convenient to use the body mass index (BMI): weight (in kilograms) divided by the square of height (in meters), or kg/m . The acceptable range of the BMI has been given in the United States as 19-25 (Bray, 1979~. The upper limit has been well defined by many studies on the risks associated with overweight. The lower limit of 19, below which risks are said to increase again, is probably an artifact of life in industrialized countries (Rhoads and Kagan, 1983~. People tend to have low weight if they are heavy smokers, alcoholics, or in some way ill. In contrast, the average BMI of healthy people in Third World countries is typi- cally about 19 (Eveleth and Tanner, 1977), so half the population is lighter than this. Shetty (1984) in Bangalore has described poor Indian laborers who are active and apparently fit with a BMI of 16. It is interesting that, in the famous semistarvation experiment of Keys et al. (1950), the BMI of the American volunteers had fallen after 24 weeks to about 16, like that of the Indians. However, unlike the Indians, the Americans were physically and psychologically in a poor state. Young women with anorexia nervosa often have a BMI of about 14, while free of symptoms and indeed hyperactive. I am not saying that it is acceptable to have such a low BMI; what I am saying is that to my knowledge no one has systematically explored the functional effects of low body weight in adults or attempted to define a rational lower cutoff point for BMI. Children have a different and even more difficult problem. In the community, nutritional state usually has been assessed by deficit in weight for age, compared with a standard based on children in the United States. Leaving aside the question of whether the standard is appropriate, the index weight for age is unsatisfactory, because it lumps together children of low weight for
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48 height with those of low height for age. Physio- logically, these are different conditions, which, of course, can appear together. Children who are short for their age are sometimes called chronically malnourished, but I have called them "stunted"; the word might not be a good one, but it describes what we actually see. The - distinction between low weight for height and low height for age is of great public health importance. If we remove from the "malnourished" category children who are simply stunted, with normal weight for height, the prevalence of malnutrition in preschool children will, in general, be reduced by a factor of at least 5 (Table 1~. This is not just an attempt to fiddle with the numbers by changing the rules of the game. It is obviously essential to reach a decision on the question: ''Are stunted children malnourished in any useful sense of the word?" I think it is incontrovertible, from the work of Martorell (1985) and others, that stunting in the Third World is determined mainly by environmental, and not by genetic, factors. Two opposing views about its signi- ficance have been put forth. The first, exemplified by the economist Seckler (1982), is that stunting is a useful adaptation: a small child needs less food and is therefore less likely to die when food is short. Anyway, TABLE 1 Prevalence of Malnutrition in Children Less Than 5 Years Old According to Diagnostic Criterion Condition Malnourished, according to weight for age Proportion of Children, % Vietnam Refugees 66 Napalese Sri Lankans 56 32 Malnourished, 11 7 7 excluding those who are only stunteda aReduced height compared with international standards, but normal weight for height.
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49 what is the point of having long legs? As Mark Twain said, nature is wonderful--our legs are always long enough to reach to the ground. The other view is that every child has a right, according to the United Nations Declaration of Human Rights, to develop his full genetic potential. Both these views are based on values. It is better for a child to survive than to die, but this is not a sufficient criterion. Performance must be - considered, and here there is some disagreement in the evidence. If the hillman in Nepal can carry TOO kg, twice his body weight, from the plains of India to the frontiers of Tibet, which none of us here could do, can we say that he is handicapped by being small? Several studies have shown that, in terms of maximal working capacity per unit of body weight, these stunted children are as fit as or fitter than their taller and heavier counterparts, although in absolute terms they might still be handicapped. A study in India showed that adolescent boys who had been stunted from childhood and were short for their age had less chance of earning wages as farm laborers and were therefore perhaps condemned to a vicious circle of poverty (Satyanarayana et al., 1979~. It is well established that environmentally produced stunting is associated with some impairment of mental function and behavior. However, stunted children grow up in a generally deprived environment; before any conclu- sion can be drawn, one has to control for macroenviron- mental and microenvironmental factors. For example, in a recent study in Jamaica, differences in height accounted ~ _ ~ __ ~ To _ ~ ~ =~ .~_ a; ^~ ;~ TO lUL ALIT} 1V~ w' ~ vow ^, _~. The mortality associated with a given degree of stunting in Zaire is different from that in Bangladesh (Van Lerberghe, 1983~. Several similar studies have been conducted, but many more are needed to get a clear idea of what it means to be stunted. It is not going to be easy to get a general answer to the question of whether stunting matters. One can take the position that any handicap matters, but not much can be done about it until one knows the cause or, more precisely, the relative importance of different causal factors. I believe that stunting is nutritionally determined, that it results from a relative deficiency of protein or factors associated with protein (see Golden, 1985), and that it can be prevented with specific nutritional measures. Whether such prevention
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so should have a claim on scarce resources will depend on what we find out about the extent of the handicaps. ADAPTATION The Indian laborers that I mentioned earlier were very thin, with only 6% body fat, but apparently fit. They also had very low food intakes. Many groups of people seem to subsist quite well on energy intakes much even w ten allowance is made for their low body weight. I believe that the new FAO/WHO/UNU (1985) requirement estimates are based on sound physiological evidence. However, most of it came from work in developed countries. What are the possibilities of some mechanism of long-term adaptation to low intakes? At least half our energy intake is lower than their estimated requirements, needed for the essential processes of maintaining life represented by the basal metabolic rate (BMR). In the Indian subjects whom I have cited as an example (Shetty, 1984), the BMR was 17% below the expected rate; that In theory, several factors could contribute to ants saving: lower rates of protein turnover and ion transport; more efficient formation of ATE, the basic unit of energy transduction in the body; and more efficient use of ATP. All these are hypothetical, but possible (Waterlow, 1986~. A useful economy can possibly be achieved by a summation of many small changes. Because they are small, they will be difficult to detect and measure, but we should at least try. ,, constitutes a considerable saving. The next need for energy is for physical activity. ~ ~ ~ not for all, energy cost is For most activities, although proportional to body weight, so here again cne sma'' person has an advantage. If one has a given task to perform, such as walking 5 miles or plowing a field, and time is no object, there could be a most economical rate of doing it--neither too fast nor too slow. The findings of physiologists vary on this, and the optimal rate depends on the load. I think it quite likely that for many purposes it is more efficient to work slow than fast and that people have developed by experience the most economical pattern of work. We badly need accurate studies on this subject under the conditions of developing countries.
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51 Skeletal muscle contains two types of fibers, the so-called fast-twitch and slow-twitch fibers, with different functions. There is some evidence that the slow fibers are biochemically more efficient than the fast fibers and use less energy for the production and maintenance of a given force. The relative proportions of these two types of fibers in a particular muscle are not necessarily the same in every person. Therefore, one would expect that people with a higher proportion of slow fibers would be able to work more economically. Exercise physiologists believe that the capacity to be either a sprinter or a marathon runner is determined by genes, not by training. Perhaps Third World people have undergone a genetic selection of fiber types that allows work to be done in the most economical way. I have discussed these speculations in more detail elsewhere (Waterlow, 1986), but they open lines of research relevant to the problems being considered here. INFECTION So much has been written on nutrition and infection that I hesitate to add to it. I wish to refer here not to specific infections, such as measles and malaria, that are preventable by specific measures, but to the much less well-characterized diarrhea! diseases and respiratory infections. The point is often ignored that the biggest risk factor for dying from an infection is to be very young. Figure 1 is based on data from the Pan American Health Organization (PAHO) Child Mortality Survey (Puffer and Serrano, 1973~. Even if the neonatal period is excluded, twice as many deaths occur between the ages of 1 and 6 months as between the ages of 6 and 12 months. Almost half the deaths were attributed retrospectively to diarrhea! disease, even though most of the children were breast-fed. The prevalence of diarrhea is certainly higher in the second 6 months, but the mortality is higher in the first 6 months. Why should these infants be so susceptible? Evidence is accumulating that growth in both weight and length in these poor communities begins to falter in many cases well before 6 months of age, presumably because the mothers, themselves undernourished, cannot produce enough _ ~
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52 ~ 24 o - I 111 1 6 C) o m z a: 8 o _ ~ 6 7 8 9 % OF DEATHS FROM DIARRH EAS 44 C46, 51 1 2 3 4 5 AGE IN MONTHS 10 11 FIGURE 1 Proportion of postneonatal deaths in first year of life attributed to diarrhea! disease. Data from Puffer and Serrano, 1973. milk. There is also evidence, from somewhat older children, that nutritional status has little effect on the incidence of infections, but much influence on the duration and severity of infections (Tomkins, in press). From observations of these kinds, I draw two conclusions--one specific, the other more general. The specific conclusion is that a baby well nourished during the first 6 months of life will have a very good chance of withstanding the infections that are almost inevitable during the weaning period. I am glad that WHO is now giving more attention to the question of early supple- mentary feeding, whenever it might be needed to maintain the health and growth of the child. My general conclusion is that the programs that during the last 2 decades have focused on the preschool child (up to the age of 5 years) have to a large extent been misdirected and wasteful, in that they have not taken enough account of the biology of young children and
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53 of the natural history of disease in this age group. The pattern of mortality in the first year that emerged from the PAHO survey was for me a true eye-opener. It ran counter to what I had been taught, which was that children in developing countries are likely to be healthy for the first 6 months of life, provided that they are breast-fed. In our emergent priorities, much more attention should be riven to the first year, because that _ _ . ~ ~ ~ ~ · ~ ~ · ~ ~ ~ Is when the tuture or one prescnoo' can a ~ s aecerm ~ luau . As a practical recommendation, I suggest that, wherever there is a system for recording deaths, they be "ratified and reported in monthly age groups for the first year. ___ , This simple measure would provide a rapid and sensitive index of the effectiveness of preventive efforts. SCARY I have taken the opportunity of this important meeting to suggest some ideas that are speculative or controversial. I would like to end by making clear what I Am not saying. I am not saying that there is no role for macromeasures of the kind discussed by other participants here. To do so would be presumptuous and ridiculous. But such measures take a long time, so we need an emer- gency strategy. 0 I am not saying that the kind of operational research being done under the auspices of the Subcommittee on Nutrition of the United Nations Administrative Committee on Coordination with the leadership of Dr. Horwitz is not necessary and valuable. I am not saying that action must wait for research. As a doctor, I do my best to treat a patient even if I do not fully understand his disease. I am saying that rational choices about priorities for action require more biological knowledge than we have. My job has been to answer the question: What kind of knowledge? I have given some examples, but the list is far from complete. There are plenty of challenges for the young scientist who wants to make a contribution in
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54 nutrition. Let me end by stressing again the vital importance of basic research in nutritional science as a foundation for effective policies. The point was made very eloquently by Hirschman (1963~: The lag of understanding behind motivation is likely to make for a high incidence of mistakes and failures in problem-solving activities and hence for a far more frustrating path to development than the one in which understanding paces ahead of motivation. It should not be necessary to say this again more than 20 years later, but unfortunately it is. REFERENCES Bray, G. A., Ed. 1979. Obesity in America. 2nd Fogarty International Center Conference on Obesity. National Institutes of Health Publication No. 79-359. Bethesda, Md.: U.S. Department of Health, Education, and Welfare. Elton, G. A. H. 1978. standards of need. Needs and Wants. Publishers. European diets in relation to In J. Yudkin, Ed. Diet of Man: London: Applied Science Eveleth, P. B., and Tanner, J. M., Eds. 1977. Worldwide Variation in Human Growth. Cambridge, U.K.: Cambridge University Press. Galbraith, J. K. 1982. A Life in Our Times. New York: Ballantine Books. Golden, M. H. N. 1985. The consequences of protein deficiency in man and its relationship to the features of kwashiorkor. In K. L. Blaxter and J. C. Waterlow, Eds. Nutritional Adaptation in Man. London: John Libbey. FAO/WHO/UNU (Food and Agricultural Organization/World Health Organization/United Nations University. 1985. Energy and Protein Requirements. Report of a
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55 Joint FAO/WHO/UNU meeting. World Health Organization Technical Reports Series No. 724. Geneva: World Health Organization. Hirschman, A. O. 1963. Journeys Toward Progress: Studies of Economic Policy Making in Latin America. Westport, Conn.: Greenwood Press. Jolly, A. R. In press. Contributions of the UN agencies to nutrition: UNICEF. In Proceedings of the XIII International Congress of Nutrition. London: John Libbey. Joseph, S. C. 1985. Realistic approaches to world hunger: public health measures. Food Nutr. Bull. 7~1~:5-9. Keys, A. B., J. Brozek, A. Henschel, O. Mickelsen, and H. L. Taylor. 1950. The Biology of Human Starvation. Minneapolis: University of Minnesota Press. Lipton, M. 1983. Poverty, Undernutrition, and Hunger. World Bank Staff Working Papers No. 597. Washington, D.C.: World Bank. Martorell, R. 1985. Child growth retardation: a discussion of its causes and its relationship to health. In K. Blaxter and J. C. Nutritional Adaptation in Man. Puffer, R. R., and C. V. Serrano. Waterlow, Eds. London: John Libbey. 1973 Patterns of , , . Mortality in Childhood. Report of the Inter-American Investigation of Mortality in Childhood. Pan American Health Organization Scientific Publication No. 262. Washington, D.C.: Pan American Health Organization. Rhoads, G. G., and A. Kagan. 1983. The relation of coronary disease, stroke, and mortality to weight in youth and in middle age. Lancet 1:492-495. Satyanarayana, K., A. N. Naidu, and B. S. Narasinga Rao. 1979. Nutritional deprivation in childhood and the
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56 body~size, activity, and physical work capacity of young boys. Am. J. Clin. Nutr. 32:1769-1775. Scrimshaw, N. S. 1985. Realistic approaches to world hunger: policy considerations. Food Nutr. Bull. 7~1~:10-14. Seckler, D. 1982. tlSmall but healthy: a basic hypothesis in the theory, measurement and policy of malnutrition. In P. V. Sukhatme, Ed. Newer Concepts in Nutrition and Their Implications for Policy. Pune, India: Maharashtra Association for the Cultivation of Science, Research Institute. Shetty, P. S. 1984. Adaptive changes in basal metabolic rate and lean body mass in chronic undernutrition. Human Nutrition: Clinical Nutrition 38C:443-451. Streeten, P., S. J. Burki, M. ul Haq, N. Hicks, and F. Stewart. 1981. First Things First: Meeting Basic Human Needs in the Developing Countries. Oxford: Oxford University Press for the World Bank. Tomkins, A. M. In press. Protein energy malnutrition and risk of infection. Proc. Nutr. Soc. United Nations University. 1984. Strengthening developing country institutions concerned with food and nutrition. Food Nutr. Bull. 6~3~:17-28. Van Lerberghe, W. 1983. Anthropometric assessment of young children's nutritional status as an indicator of subsequent risk of dying. J. Trop. Pediatr. 29:69-75. Waterlow, J. C. 1981. Sixth Boyd Orr Memorial Lecture. Crisis for nutrition. Proc. Nutr. Soc. 40~2~:195 207. Waterlow, J. C. 1986. Metabolic adaptation to low intakes of energy and protein. In R. E. Olson, E. Beutler, and H. P. Broquist, Eds. Annual Review of Nutrition, Vol. 6:495-521. Palo Alto, Calif.: Annual Review Inc.
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57 DISCUSSION OF PROFESSOR WATERLO~'S PAPER DR. MARTORELL: Dr. Waterlow has said a number of very important things, particularly on the subject of small body size and on whether stunting merits concern. I would like to present for consideration a scenario in which we have moved into the twenty-first century, and economic development has already taken place. There -are no problems of malnutrition, and a group of nutritionists is told by a government, "We don't have any small people anymore and we need them for intergalactic travel. Fuel and food requirements will be reduced if flights are staffed with small people. So, the question is, what is the formula for small people? How can we produce small people?" The answer would be that one would need to interfere with development in early childhood--and would require frequent infections, particularly diarrhea! diseases; very poor diets, with nutrient deficiencies and limitations in energy; and problems with infant feeding, such as inappropriate timing of complementation of breast milk. The formula would specify these and other factors, and we would have to admit that production of small people would be very inefficient, because many children would die. There would be effects other than small size on a variety of functions, including mental development. There would be reduced immunocompetence and more severe infections. Wasting would also result; small people could not be produced without wasting, because the two conditions are very closely related. .. ~. . ~ In summary, the formula for small people would be infection, poor diets, and malnutrition during early childhood. If we focus on the causes of small body size, rather than on small body size itself, we obtain a different perspective on whether stunting merits concern. Focusing on small body size alone is misleading. Males who sur- vive the tumultuous early period and Become small adults are able to function in most settings, but agricultural productivity may be impaired. For small adult females, there are likely to be problems in reproduction, and the next generation would be affected. Although the energy requirements for agricultural tasks might be reduced and less food might be needed to survive and work, small body size should not be seen as an adaptation. It is the formula for producing small people that I want to emphasize as the problem.
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58 DR . WATERLOW : I agree that we need to know the causes. I take the simplistic view that the deficit in linear growth is an effect of inadequate protein intake; it is related to a specific factor or some substance associated with protein. I do not agree that biologically the phenomena of wasting and stunting are necessarily connected. In real life, of course, cney are often connected, but there is no statistically valid association throughout the world between stunting and wasting, as Dr. Mahler has shown. Still, I agree that we need a better analysis of the causes. DR. SCHORR: My question has to do with nutritional assessment. In the light of Dr. Mellor's comments on the numbers of malnourished people in the world today, are the current nutrition assessment tools and derived indicators sensitive, specific, and adequate to detect the extent of malnutrition, and are the types of data being reported or the methods of reporting accurate? What type of research or practical applications would improve the quality of data for assessing the severity of global malnutrition? At the nutrition congress, Dr. Rohde addressed some of these issues. Perhaps he could speak on this issue. Is there a problem with this reporting? Is it a problem with severe malnutrition or mild-to-moderate malnutri- tion? What sorts of things can be done? There appears to be some sort of a gap between assessment and accurate reporting. DR. WATERLOW: Of course there is a problem. The whole thing is a continuum from perfectly healthy to dead, and you can assess where you are on it through various anthropometric methods. What we all want to know are the functional consequences of being at any point on the continuum--not an easy thing to determine. It will be necessary to decide what functions you are interested in--physical work, mental development, or behavior. The relation between an anthropometric deficit and a func- tional deficit depends strongly on culture and on all sorts of factors. ~ ~ ~ ~ ~~ The risk of excess moray an a given weight deficit is about 5 in Bangladesh and 1.5 in Zaire. Presumably, there is a range of different factors in these two countries. The same would apply to any
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so functional deficit, and this idea that you can take some measurements and assess them in some sort of accurate way is simply a cloud. What we can do is identify children who are in a serious nutritional state. There might be some argument at the edges, but anyone who has worked in clinical nutrition can do this. Those are the people whom I am suggesting we concentrate on. Otherwise, we are doing nothing. UNIDENTIFIED SPEAKER: In the slide you showed [Figure 1], the case-fatality declines over the preschool years, with the peak in the age group of 1 month. How much of that was not confounded by the low birth weight of these babies? This makes us wonder how early is early enough for intervention, such as changes in maternal nutrition during pregnancy. DR. WATERLOW: That is a very good question. It was not the case-fatality ratio that declined, it was the actual number of deaths. I left out the neonatal period. Results of the work in Guatemala and Costa Rica suggested that a very high proportion of the neonatal deaths result from prematurity. There are, of course, other complications. I agree that we should intervene as early as possible in pregnant women. Dr. Whitehead's results in West Africa suggested that supplementary feeding of pregnant women can have a significant effect on birth weight. So, I agree, we should start as early as possible. DR. ROHDE: There is considerable basis for debate over the question of functional significance of smallness, and one can look at it either from the perspective of Dr. Martorell (how to get a small population) or from the perspective that Dr. Waterlow has offered (how to deal with this huge problem in the world and focus our resources on the people who need them the most). The latter gives us the perspective that Dr. Waterlow offered of looking at the most severely malnourished and deciding what can be done about them, what the functional consequences are. and which of them are most in need of help I suggest a compromise. think that the implication in the comments is that, if we start early enough and take the appropriate measures, we will not have to tolerate either wasting or stunting.
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60 We should start interventions very early, as was just pointed out, during the prenatal period, or (as Dr. Martorell suggested) even one generation ahead. We should look for healthier mothers and healthier children, monitor the growth of the children, and do something about it in the first 6 months of life. Thus, we do not wait until we have a malnourished child on our hands who all of us find to constitute an almost impossible clinical task. That is how we have to approach it. Although the preventive approach does commit us to do something for every child, a later approach to those who are malnourished does not seem to be within our capacity. DR. WATERLOW: I like to agree with compromises. I agree with you, Dr. Rohde, about a concentration on the first 6 months of life. I also think that for countries where there are many seriously malnourished children, we have to do something about it. We have to show a willingness and an ability to save those children's lives. This will also make a contribution to mothers' understanding of how to treat their children. UNIDENTIFIED SPEAKER: If we omit the very severely malnourished child, how comfortable are you that we know chat ~nthrnn~m~tri ~ tori sari ~ should be applied during the r r ~ ~ first 6-12 months of life to identify the small child that you and Drs. Martorell and Rohde have referred to? DR. WATERLOW: That is impossible to answer. How appropriate are criteria? All we can do is work according to results. -~ What an ordinary person ages, 1 think, In looking alter children is say that, if they are at a particular weight at a particular age, they are pretty healthy and, that, they are not. if they are beginning to fall below This attempt to define quantitative cutoffs granted that we have to have growth charts and references, is not terribly useful. UNIDENTIFIED SPEAKER: I would like to return to nutritional science. As you said, we are in a state of transition in nutritional science. Much of nutritional research is retreating or being partitioned among the basic sciences these days, and room for nutrition itself in the laboratory is disappearing.
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61 At the some time, advances in genetics might entirely change the way we view requirements within the next 10-20 years. I suspect that the role of nutritionists will change, and even the name. I am concerned that the baby not be thrown out with the bathwater in all this--that the multidisciplinary focus on human beings be maintained in this process. With regard to your recommendation that more institutes of higher education and nutrition be set up in developing countries, I am worried about the degree to which people are willing to invest in such institutions. If they are unwilling to send students to industrialized countries to study science and to pay for a full course of study--not just 3 or 6 months, but the full 5 years that it takes to bring people to the expertise expected of scientists here--we are going to be fostering a form of international apartheid where we have different standards. We have a misleading separate-but-equal concept of what institutions will do overseas. Do you see that as a concern as to the amount that should be invested in these institutions? DR. WATERLOW: Thank you for your comment about nutritional science in general. As far as the insti- tutions are concerned, I was not suggesting that vast numbers of completely new institutions be established. My own work has always been in a special institute within a university and medical school. Universities and medical schools need to be strengthened. My attitude has been that people from developed countries have the responsibility to help to develop the intellectual potential of people in the developing countries. I do not accept that there are necessarily going to be first- and second-class citizens. In Jamaica, we have a master of science course in nutrition that is recognized as being good as any. There is no reason for the situation to be otherwise--and it is not--for courses in India and other parts of the world. I think that it is a colonialist point of view to say that it is bound to be worse because it is there, rather than here. . . . . . .. . .
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Representative terms from entire chapter: