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David Seckler. Ford Foundation, New Delhi, India, and Colorado State University, Boulder, Colo., United States
Small but healthy
Food toxicity and anti-nutrients
Small but efficient
In this paper I describe my attempts as an economist to come to grips with the world of malnutrition. The process began with a simple attempt to estimate a minimum wage for agricultural labour based on food requirements and costs. I soon found, however, that the nutritional parameters upon which such calculations depend are based on very questionable assumptions regarding body size and nutritional requirements. As a consequence, I hypothesize that perhaps as many as 90 per cent of the people in the world who are normally classified as "malnourished" may only be "small but healthy" people. This is not to deny that anthropometry is an index of poverty, or that small but healthy people desperately need an improvement in their economic situation. The hypothesis does, however, indicate that the problems these people face are primarily socio-economic problems, and not of "malnutrition" per se.
When I was asked to address this meeting on my work in nutrition policy I gladly accepted. I have been spending most of my time talking to nutritionists about these problems and perhaps not enough time talking to economists. I say this not only because of the obvious connection between nutrition, food policy, and agriculture, but because of a discovery of, in my opinion, considerable consequence. This discovery is that the concept of malnutrition cannot be comprehended except in terms of the economic theory of optimality.
In order to understand what I mean by this statement it is first necessary to understand that malnutrition is an extremely ambiguous word. The Random House Dictionary, for example, defines malnutrition as "lack of proper nutrition". Since proper nutrition is not defined, one must simply assume that it is "lack of malnutrition." As Ford (1964) observes:
The term "malnutrition" has been in use for a very long time and appears to be self-explanatory but even the briefest perusal of the vast literature on nutrition raises grave doubt about that. There is no way of knowing if the word has the same significance in all parts of the world or if its interpretation lies, like beauty, in the eyes of the beholder.... Anything less scientific than this chaotic inexactitude would be difficult to imagine.
The problem is that there are two quite different criteria of "proper nutrition" and "malnutrition." Under one criterion proper nutrition is defined as sufficient intake of nutrients to reach the full genetic growth potential of the individual defined by various anthropometric and nutritional standards. Malnutrition then becomes abnormally "low size" and/or inadequate food consumption. Under the second criterion, malnutrition is defined in terms of certain clinical signs of nutritional inadequacy and/or indices of functional impairment, such as the inability to work productively. Proper nutrition then presumably becomes the absence of these clinical-functional signs of malnutrition. The problem is that most of the people who are not properly nourished under the first criterion are also not malnourished under the second criterion! There exists a considerable grey area, consisting of perhaps as much as 80 per cent or more of the conventionally estimated world of malnutritions, who are neither properly nourished nor malnourished. They are simply "small but healthy" people who have attained an optimum size with respect to their environment.
In the course of the following discussion I would like to describe how I arrived at this conclusion - my "intellectual odyssey," as I have called it. I have chosen this mode of presentation primarily because it appears to me to present the most convenient format for reducing a rather lengthy research effort to a short discussion; but also, because I am interested in the philosophy of science, and I have personally found the process of "conjecture and refutation," as Karl R. Popper describes it, over these past three years one of the most exciting intellectual episodes of my life. Thus I will speak to some extent of my personal experience, and to those who think that this has no place in academe, I can do no better than cite our colleague William Foltz, who once said in introducing his remarks on a paper he was about to review: "Gentlemen, I apologize for citing my personal experience - but, gentlemen, it is the only experience I have had."
My interest in nutrition began in the summer of 1977 when I came to India on a short-term consulting assignment to the Central Soil and Water Research Conservation and Training Institute, Dehra Dun. The assignment, I thought, was quite simple: to do economic evaluations of various projects of the Institute in rather remote and isolated areas of India, particularly in the "hill areas" of the Himalayas.
The specific problem I encountered was that in the highly under-employed and poverty stricken area of the hills - and, I later found, generally throughout India - people would not work for less than about Rs 5 (or about $0.60) per day. l thought it peculiar that people appeared to be willing to starve rather than work for this, under Indian conditions, not inconsiderable wage. The fact of this wage floor was of course of considerable importance to my evaluations because while it is conventionally assumed that the shadow price of labour under conditions of unemployment is zero, or near zero, this fact seemed to me to indicate that there was a real cost of labour in keeping this wage floor in place. Let me say at the outset that I do not believe that "culture" or "work-leisure" preferences are very relevant in this domain of abject poverty. Something more fundamental, l suspected, was going on.
It is clear that the physical energy expended in physical work must be provided by the physical energy provided by food. Thus there must be a fundamental connection between earnings, which are used mainly to purchase food, and the energy requirements of the work required to obtain earnings. l thought I would spend a few days working out this little problem and here I am, three years later, still in this most fascinating field of nutrition.
I estimated (see Seckler 1980) that a representative household of Indian agricultural labourers consisting of 5.33 people would generate about 776 days of work per year under full employment. In order to meet their energy requirements at this level of work they would require about 4,245,000 kcal per year - or, at 3,150 kcal per kg of wheat, about 1,350 kg of wheat per year. The poor indian household spends about 60 per cent of its income on food grains, 20 per cent on other food items, and 20 per cent on non-food necessities such as clothing, shelter and fuel. Thus to meet all necessities it must earn about 2,000 kg of wheat or its equivalent per year. At full employment, the daily minimum food-grain wage would be 2.6 kg. Assuming that men earn 20 per cent more than women, the minimum male wage rate would be 2.9 kg of food grain. l later found that this estimate corresponds remarkably close to Clarke and Haswell's survey (1970) of agriculture wage rates in subsistence economies. They observed . . . "the strange fact that . . . throughout all times and places for which we have information, the rural labourer, however poor, will not do a day's work for less than three kilograms grain equivalent."
It is difficult to convert this minimum food-grain wage into monetary terms without detailed knowledge of local diets and costs of food grains and other necessities. However, following the estimates of Dandekar and Rath (1971) for rural India in 1969/70, and adjusting for inflation to 1977,1 found that the Rs 5 figure was perhaps as close as one could conceivably arrive at. l concluded that the energy-work connection is indeed decisive in setting such wage floors as I had observed.
The one snag in this conclusion was that the Rs 5 figure was based on the assumption of a fully employed household. If unemployment existed to the extent of 20 per cent, with only 600 days of work per year, the minimum daily wage would have to be about Rs 5.8, or 16 per cent more than the observed floor (the relation is non-linear due to savings of calories and other necessities in unemployment).* For reasons explained below, I later discovered that I had overestimated kcal requirements, and thus the Rs 5 figure was probably about right with 20 per cent unemployment .
From this point I naturally became interested in the mechanism through which this apparently universal minimum food-grain wage would be established. The classical theory of the subsistence wage immediately comes to mind. But this theory is a long-run theory depending on the regulation of the aggregate supply curve for labour through attrition of children and, while obviously true as a long-run phenomena, it did not appear to me to be adequate for the essentially short-run, nearly day-to-day equilibrium that I seemed to detect even in the case of the individual household.
The answer to this problem is quite specific and direct in the nutritional literature. In the classic starvation studies of Keyes, there is shown a very clear production function between energy intake and work ability and work performance. Interestingly, under starvation, work performance decreases before work ability due to the mental and emotional stress of deprivation. There is no time here to review this long and fascinating study but I would like to say that, if one wished to understand the "economics of being poor" - which, I agree with Shultz, is the only economics that realty matters - one should study Keyes. As a labourer's wage falls below 3 kg per day under the competitive pressures of underemployment, his productivity decreases. As his productivity decreases, there is more downward pressure on his wages as the employer tries to pay him at most the value of his marginal product. However, this vicious circle must soon end because the labourer "gets sick." The body throws out a complex variety of defence mechanisms: slowness, drowsiness, lethargy, stumbling, and fainting (quite a common sight in Indian fields) - which causes the labourer to be dismissed. As more of the labouring class are disabled by low wages, a labour shortage develops and wages are restored to their energy equilibrium level. Of course there is nothing above equilibrium in this model to stimulate a higher wage because once the labourer can purchase enough energy to do the work, the marginal product of the energy-wage is zero.
This analysis seems to me to be perfectly satisfactory but it depends on one crucially important and, I find, entrancing assumption. This assumption is that the wage-earners in a household love their dependants to such an extent that they will, in a sense, "irrationally" share their scarce food supplies with them in proportion to their needs. The 3 kg equilibrium figure assumes that the wage-earners do not make their dependants bear the nutritional burden of low wages. If they treated the dependants as residual claimants on scarce food supplies, as is commonly thought, the equilibrium wage would be much lower than 3 kg per work day. In principle, it would be reduced, as the dependants died off, to about 1.8 kg. It is reasonably certain that sharing takes place because the poorest and most malnourished households are also the largest households. I have tried to check this sharing assumption in detail by examining data on the age and sex distribution of anthropometric indices (weight, height, weight for height, etc.) in poor Indian households relative to the regular anthropometric standards. My tentative conclusion is that, except for under-estimation of the additional nutritional requirements for growth of children, and the additional requirements of pregnant and lactating women, the gap between anthropometric reality and standard is uniform across age and sex groups within the household. The household, in other words, attempts to share the burden of malnutrition as uniformly as it can estimate - and, indeed, for reasons outlined below, it possibly estimates requirements for the special groups more rationally than do nutritionists. One of the more provocative results of this preliminary analysis is that by anthropometric criteria, the female members of the typical Indian household appear to be slightly better off than the males. I have received a few "arrows of outrageous fortune" for corroborating the intuitively obvious fact that fathers and husbands do indeed love daughters, wives, and mothers.
With these general conclusions I completed what I now look back upon as Phase I of my work in nutrition. But it soon became obvious that there remained a basic problem in this position that launched me into a much deeper study of nutrition than ever I had contemplated.
The Phase I problem was this. If one takes the commonly accepted energy requirement of 2,250 kcal per capita per day for the Indian population, converts this figure into earnings in the manner indicated in the preceding section, and then estimates the incidence of malnutrition in India as those below a certain minimum earnings, one finds, as Dandekar and Rath (1971) have shown, that about 40 per cent of the rural population of India do not earn enough to meet minimum calorie requirements. This conclusion is not extraordinary in itself: India is a poor country. But the extraordinary thing is that if one calculates the degree, or severity, of malnutrition in India, one finds that nearly 20 per cent of the rural households do not earn enough to meet minimum necessities, provide their energy maintenance costs, and do any work at all. In India, if poor people cannot work they cannot survive. I considered this fact a refutation of the quantitative basis of my previous position. There were only two possibilities I could see: either the method of estimation was incorrect; or the 2,250 kcal standard was too high - or, as I have since concluded, both.
I shall not go into the estimation problem here as it would require too much time. Rather, I shall concentrate on the problem presented by the 2,250 kcal requirement.
Here it is important to note that I have only a superficial knowledge of the biochemistry of nutrition so that my arguments are only those of an economist, together with some rather common observations available to everyone (except, it sometimes seems, to nutritionists! ).
One of the many pleasant surprises about India is that as one travels through the country one simply does not see anything like the extent of malnutrition one expects to find from the available data, much less the popular press. Not being a trained nutritionist I cannot trust my own observations so I make a habit of asking trained people to estimate the incidence of severe malnutrition in the populations in which they work. With the exception of an area in eastern Uttar Pradesh, which is generally considered one of the worst areas of India, the response has varied between 1 to 3 per cent of the population. In this area it was 20 per cent. This seems to me to be an extraordinarily small incidence of severe malnutrition in a population that is presumed to be 40 per cent malnourished.
I might pause here to mention that there is a considerable body of opinion that holds that in most areas of rural India there has been a notable improvement in the nutritional status of people over the past decade even though per capita food consumption has remained the same or even decreased. While this opinion is not universally held, I believe that it is probably valid. There are two reasons for this belief. First, the enormous advances in control of diseases and extension of medical services, discussed by Ram and Schultz (1979), have undoubtedly increased the efficiency of conversion of food input into output by lowering the amount of "food wastage" through diarrhoea and other health factors. (Also, there is the common mistake of diagnosing symptoms of diseases - such as the "pot belly" of malaria - as malnutrition Secondly, it is possible that since the marginal propensity to consume food is very high in India, real gains in agricultural production are underestimated by food disappearance in home consumption and by upgrading food products - namely, converting food grain into milk products or better qualities of food grains. But this is a problem I cannot examine further here.
While one does not see a great deal of obvious malnutrition in India, one does see a lot of extremely small people - and the poorer people are, the smaller they tend to be. As one of my friends has observed, small people seem to do all the heavy work in India, including carrying the luggage of large people at Delhi airport!
Now this is a very important fact, if it is a fact, because the nutrient requirements of an individual of given sex, age, and activity level are a function of body surface area - or, approximately, of weight. It follows that if the poor weigh less than the weight assumed in the calculation of nutrient requirements, their real nutrient requirements will be less than their assumed requirements at any given point in time. I have been tracking this thin red line through the nutritional literature for the past two years and have concluded that most of the people of the world who are considered malnourished are simply "small but healthy" people.
This conjecture may be illustrated by some statistics from a recent study of nutrition in the five poor countries of Nepal, Sri Lanka, Togo, Liberia, and Lesotho (McKigney 1979). The incidence of malnutrition by anthropometric criteria ranged from about 55 per cent in Nepal to 20 per cent in Liberia. However, about 90 per cent of all the malnutrition found in these countries was in people with a low height for age but with the proper weight-for-height ratio. Now, if one thinks of malnutrition in the conventional imagery of thin, wasted bodies, rather than in terms merely of short people, the incidence of malnutrition must be considerably reduced. Of course, since short people with the proper weight-to-height ratio will also be light people, their consumption requirements will also be less than conventionally estimated.
One naturally wonders if there is anything wrong with these small people other than their smallness. Oddly enough, there has been very little study of these "mild to moderately malnourished" (MMM) people. Jelliffe (1966) observes:
In as yet ill-defined dietary circumstances, protein-calorie malnutrition - probably when mildly moderate and prolonged - results in nutritional dwarfing - that is, in children who are "considerably underweight and undersized, while at the same time appearing to have relatively normal body proportions." (Jelliffe 1959). As Downs (1964) remarks, children with nutritional dwarfing are light in weight, short in stature, with relatively normal body proportions and sub-cutaneous fat appropriate to their weight; they are likely to be taken for healthy younger children. This condition has received inadequate attention but appears to be common in Peru (Graham 1966) and in Arab refugee children in the Lebanon (Puyet, Downs and Budier, 1963, Downs, 1940).
There is a haunting picture in Jelliffe's excellent book which shows two babies of the same height, yet one is six months old and the other eighteen months old. The eldest "looks," if anything, better than the youngest. Looks are deceiving, but the caption does not indicate any difference between these babies other than age and, as Jelliffe indicates in the above citation, if one does not know the age of these "nutritionally dwarfed" children, "...they are likely to be taken for healthy younger children."
Are they, in fact, small but healthy children? Certainly, most of the literature assumes that they are not. But without independent evidence of functional impairment the meaning of this kind of malnutrition becomes highly ambiguous. If, on the other hand, they are in fact healthy, then one must wonder how they became abnormally small, retaining the appropriate weight-to-height ratio, and their health. Is it genetics? (The incidence of "malnutrition" in the five-country study is highest in the two Asian countries.) Or, is something more involved? If so, what?
It is not surprising that medical and nutritional scientists interpret variations in human growth as the result of variations in health and nutrition. But as J.M. Tanner (1978) argues, recent advances in genetics, endocrinology, and other fields involved in the study of growth are creating a fundamentally different view of the process of growth. Tanner recommends that the study of growth should become a field of its own, the field of "auxology," in which health and nutrition contribute a part, but only a part, of the explanation of a far more complex and even sophisticated growth process than has hitherto been contemplated.
The prevailing theory of growth and nutrition may be described as the deprivation theory. Under this theory, it is assumed that every individual is born with a given, genetically determined, potential growth curve. If the individual is healthy and well nourished, he will grow along this curve. Per contra, growth significantly below this curve indicates poor health and/or malnutrition. Of course some people are normally small, and it is difficult to determine if any small individual is abnormally small or not. But in large populations a skew of the distribution curve of size toward the small is regarded as evidence of poor health and malnutrition in that population.
In contrast to this view, there is an alternative perspective which may be called the "Homeostatic Theory of Growth." This theory is based on a substantially different genetic interpretation in which the sing/e potential growth curve of the older view is replaced by the concept of a broad array of potential growth curves in several anthropometric dimensions - in a word, with the concept of a potential growth space. Within the bounds of this potential growth space the growing child may be rather indifferently mapped through various paths of size and shape in response to nutritional and other sources of information from the environment.
The principal instrument of control in the homeostatic process is control over the rate of growth of the child. If nutrient constraints are encountered at a given rate of growth, the rate is slowed to bring nutrient demand into equilibrium with nutrient supply. By thus regulating the speed of internal, physiological "clocks," short-term equilibrium is established and the ultimate size and shape of the adult may be moulded to its environment.
Of course, there are limits to these adaptive possibilities. It is an important mathematical property of homeostatic models that while they maintain stability within limits of variation, they disintegrate into violently unstable paths when the bounds are transgressed (Sukhatme and Margen 1978; Sukhatme 1979).
If the homeostatic theory is correct, then the dilemma of "nutritional dwarfs" who are not observably impaired in the range of mild to moderate malnutrition (M M M) is resolved. There are no impairments because this range represents an adaptive response of body size to adverse conditions in order to avoid the impairments. I have tested this conjecture on a sample of Indian children who were medically screened and known not to be malnourished nor unhealthy, and who had a normal medical history (ICMR 1972). Over 90 per cent of the 17-year-olds in this healthy sample would be considered malnourished by conventional standards used in nutritional assessment studies - many of them moderately malnourished and some even severely malnourished. Chen et al. (1978) found a high incidence of mortality in Bangalee children at the severe level of malnutrition but a normal incidence of mortality (and, probably of morbidity) in the range of MMM. Beaton and Ghassemi (1979) could find little if any output in terms of mortality, morbidity, and even growth in MMM children in the supplementary feeding programmes they surveyed. I believe that the idea that there is a continuous relationship between the various degrees of malnutrition and clinical-functional signs of malnutrition is a statistical illusion generated by the habit of curve fitting over all the malnutrition levels together. If the regressions were made separately for each level of malnutrition I believe that it would be found that all the significant relationships would be found in the severe level with no significance at the levels of MMM. (This statistical problem, incidentally, is the same as that leading to the illusion that there are significant economies of size in American agriculture (Seckler and Young 1978).)
From the basic theoretical framework of homeostatic control of the growth process it is but a short step to a conventional economic model of how the control mechanism might be expected to result in an optimum size of a person given the marginal benefits and costs of size. A study of piece-work wage earnings by weight of workers appears to yield the typical "S"-shaped production function, which, if matched up with a linear food cost function related to weight, would yield an optimum somewhere in the mid-range between the largest and the smallest workers (see Gopalan 1975). This curve has often been interpreted as though it demonstrated that the best size is the largest because total product increases through to the maximum size. This interpretation is valid, as any economist knows, only if the marginal food costs of size are zero. while this condition is perhaps satisfied for rich people who consume for pleasure, it certainly is not the case of the poor who must consume for nutrition. Thus with the optimality theory showing that it would be desirable to be small under conditions of food scarcity and the homeostatic theory showing that it is in principle possible to be "small but healthy," this aspect of the argument is conceptually complete.
The policy implications of this analysis can be addressed in terms of three distinct "Worlds of Nutrition." world 1 consists of "properly nourished" people as defined by received anthropometric and nutritional standards. world 2 consists of people who are not properly nourished but who are also not functionally impaired. The available evidence indicates that these small but healthy people have been able to adapt their size - and, therefore, their consumption requirements - to less than standard levels without suffering adverse effects. world 3 consists of people who have been pushed below the threshold of adaptation. These people are small, undernourished even for their size, and functionally impaired.
Roughly speaking, world 2 corresponds to MMM people comprising 80 to 90 per cent of all people not of world 1, with the balance of world 3 people either at the severe level of malnutrition, or in clear and present danger of severe malnutrition From a policy point of view the crucially important distinction between worlds 2 and 3 is that needy people in world 2 can, while those in world 3 cannot, work if given the opportunity. I believe that food-for-work programmes (FFWP) should be the principal instrument of policy for world 2. These programmes should be integrated with clinical programmes that provide nutritional and medical care and job training to world 3 people so that they can be enrolled in FFWP when they are in condition to work.
The great advantage of FFWP is that they provide both an effective means of excluding less needy people from the income benefits of food aid and a permanent improvement in the economic environment in which these people must live. Since people must do hard manual work in FFWP only the most needy will enrol. Since FFWP creates permanent community assets in the form of roads, schools, hospitals, drinking water, irrigation, and the like, they lay a basis for sustaining the improvements created by food aid. FFWP also provides a mechanism for eventually liquidating the clinical programmes necessary for world 3 people. In my opinion, all other programmes, such as school lunch programmes and supplemental feeding programmes for at-risk groups, should be used only as a last resort when there is good reason to believe that the FFWP-based programme is inadequate.
There are three reasons why I am sceptical of these other programmes. First, since they are very inept at excluding the comparatively "well-off" from the programme, they divert an enormous amount of resources from the needy. Second, they are targeted to individuals within households, not to the household itself, and I believe malnutrition is a household problem that can only be solved at that level. With rare exceptions, malnourished individuals come from malnourished households, and these households are malnourished because the income-earning adults cannot earn an adequate living. Until this basic problem is solved, at-risk groups will remain at risk. Third, I believe that supplementary feeding programmes designed to get world 2 children up on a high growth curve can harm those children when the programme is withdrawn. The process of "disadaptation" (Beaton and Ghassemi 1979) set in motion by these programmes can easily make children unfit for the economic environment in which they must spend the rest of their lives. Oddly enough, there appears to be no follow-up study of the post-intervention lives of children who have been enrolled in supplemental feeding programmes, but I would not be surprised if it were found that such children fared worse in the post-intervention period than in their controls.
Lastly, a quantitative point. There are probably no more than 150 million people in world 3. If these people need 500 kcal of additional food per day, or roughly one-sixth kg of wheat equivalent. they would need about 9 million tons of wheat per year. At current world prices of about $200 per ton this amount of wheat would cost about US$2.000 million. Even doubling this amount for administrative and other costs results in a total sum of $4,000 million per annum to eradicate the tragedy of world 3 malnutrition
It would appear to me obvious that the eradication of world 3 should be the first priority of nutrition policy and that nutritional resources should not be squandered on the problems of world 2, problems that only economic development can solve. But until a better scientific basis is established for defining and locating people properly in these three worlds of nutrition the prevailing chaos of nutritional policy will continue. I can think of no area of scientific research more desperately needed than this.
I would like to express my appreciation to P.V. Sukhatme and Sheldon Margen for their gracious help and encouragement in this odyssey although they are not, of course, responsible for any of the views expressed here.
Beaton, G.8., and H. Ghassemi. 1979. "Supplementary Feeding Programmes for Young Children in Developing Countries." Report prepared for UNICEF and the ACC Sub-Committee on Nutrition of the United Nations.
Chen, L.C., A.K.M.H. Chowdhury, and S. Huffmann. 1978. Classification of Energy-protein Malnutrition by Anthropometry and Subsequent Risk of Mortality International Centre for Diarrheal Disease Research, Bangladesh.
Clarke, C., and M. Haswell. 1970. The Economics of Subsistence Agriculture, p. 130. Macmillan, London.
Dandekar, V.M., and N. Rath. 1971. "Poverty in India," Economic and Political Weekly, 6(1,2): 2 Jan. and 9 Jan.
Ford, F.J. 1964. "Can a Standard for 'Malnutrition' in Childhood Be Devised?" The Journal of Tropical Pediatrics, vol. X, no. 2, Sept. 1964, pp. 47-58.
Gopalan, C. 1975. "Adaptation to Low Calorie and Low Protein intake: Does It Exist?" In S. Margen and R.S. Oger (eds.), Progress in Human Nutrition, pp. 132-141. AVI Publ. Co., Westport, Conn., vol. 2.
ICMR. 1972. Growth-and Physical Development of Indian Infants and Children. Indian Council of Medical Research, New Delhi.
Jelliffe, D.B. 1966. The Assessment of the Nutritional Status of the Community. World Health Organization, Geneva.
Keyes, A., J. Brozek, A. Henschel, O. Mickelsen, and H.L. Taylor. 1950. The Biology of Human Starvation, The University of Minneapolis Press, Minneapolis, Minn., vols. 1 and 2.
McKigney, J. 1979. Simplified Field Assessment of Nutritional Status. Office of Nutrition, AID, Washington, D.C.
Ram, R., and T.W. Schultz. 1979. "Life Span, Health, Savings and Productivity," Economic Development and Cultural Change, 27(3): 399 421.
Seckler, D. 1980. "The Role of Nutrition in Economic Development. The Case of India," Transactions/Society, vol. 17, no. 6, Sept./Oct. 1980:46-50.
Seckler, D., and R.A. Young. 1978. "Economic and Policy Implications of the 160-acre Limitation in Federal Reclamation Law," American Journal of Agricultural Economics, vol. 60, Nov., pp. 575-588.
Sukhatme, P.V. 1979. Nutrition in India in Current Five Year Plans, Convocation Address. Indian Statistical Institute, Calcutta, 30 March 1979, pp. 12.
Sukhatme, P.V., and S. Margen. 1978. "Models for Protein Deficiency," The American Journal of Clinical Nutrition, 31 (7): 1237-1256.
Tanner, J.M. 1978. "Foetus Into Man: Physical Growth from Conception to Maturity," Open Books, London.
The very high uric acid levels of 40 mg per cent developed in home storage after one year would be considered unacceptable. Yet these grains are consumed, emphasizing the hazards attendant on storage. The low storage losses recorded in the same study are, after all, only one component of post-harvest losses, which are therefore much higher. When food grains of poor quality are offered on the market to the consumer, he has really no choice. If the Government finds it too expensive to remove ergotized grains from infested bajra, the consumer has a right at least to expect a replacement for infested grains that are picked out in the home. Lathyrus grains pose special difficulties. Until a genetically improved material free from toxic ß-oxalyl aspartic acid has been established, education has to be vigorously pursued regarding removal of the factor by leaching it out with boiling water. Practically all pulses carry trypsin inhibitors. Most of these are destroyed by heat, but a persistent component, perhaps tannins, are thought to be implicated. A great deal of information is available on toxins and their removal that should be transferred through an information network between developing countries faced with common problems. Within each country, a multisectoral approach was needed to relevant education at all levels, including rural women and the farmer himself. Scientists working in developing countries had a responsibility to take time off to educate administrators and policy-makers in technical matters that often strongly affect decision-making.
The inherent, genotypic smallness hypothesis rested in theory on the assumption that in developing countries growth is slowed down in a gradual way, whereas in practice it is usually a matter of bouts of infection in childhood, followed by stoppage of growth and an occasional growth spurt. These definitely reduce physical work capacity, and the same task requires a longer period to accomplish. Whether they affect mental capacity is difficult to prove, and there is equal evidence on either side. As far as is now known, about one-third of mental capacity may depend on a nutritional basis, one-third on cognitive and stimulatory factors, and one-third on such unknown factors as functional damage. Longitudinal studies are needed to correlate weight with calorie requirements, and to determine the minimal energy requirements needed for optimum health. One hypothesis is that there is some censor or feedback mechanism operative in the child that reduces the demand for nutrients in response to their shortage, leading in turn to slow physical growth, but without slowing down mental development. In existing populations, it is only third-degree malnutrition that yields morbidity patterns. Nutrition is a transscience, and one cannot always expect clear scientific answers.
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