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Vitamin A nutrition status in Costa Rica: was fortification necessary?
A national survey in Costa Rica in 1966 by the Institute of Nutrition of Central America and Panama (INCAP) in Costa Rica showed a high prevalence of low and deficient levels of serum vitamin A in 32 per cent of preschool children in rural areas. Only 12 per cent of the families in the same communities had an intake equal to or higher than that recommended for this vitamin. Clinical signs, however, were virtually absent, with not one case showing xerophthalmia or keratomalacia, and Bitot spots were present in only two children In urban areas, levels of serum retinol were higher, with low and deficient levels accounting for only 3 per cent of all cases. In general, the intake of vitamin A was much higher in the urban comunities studied than in the rural ones 11).
After that survey, vitamin A deficiency was considered to be a major nutritional problem in Costa Rica, together with protein-energy malnutrition, iron deficiency anaemia, and endemic goitre (1).
Afterwards, and following the technical recommendation of INCAP, the Government issued a decree in 1974 making mandatory the fortification of white table sugar (2). Fortification of this supposedly widely consumed food began with the sugar refined in 1975-1976. The process was followed through four consecutive years. However, supervision and control of the programme was practically non-existent, and basal information just prior to the beginning of this intervention was not obtained.
A national dietary survey made by the Ministry of Health two years later showed a striking improvement in the intake of vitamin A from food sources by preschool children, being well above the recommendations for their age group. Clinicians insisted that vitamin A deficiency was no longer a problem. A retrospective study was done on children admitted from 1964 to 1975 to the National Children's Hospital in San Jose with ocular manifestations suspected to have been caused by vitamin A deficiency. This study showed that only 17 cases among 909 had ocular signs compatible with vitamin A deficiency, 10 of them with unilateral or bilateral blindness. Most were found before 1970, all in children from rural areas 13).
At the end of 1978 and the beginning of 1979, in a joint effort undertaken by the Ministry of Health and the recently founded INCIENSA, with the advice of INCAP, serum retinol was measured in a representative sample of preschool children from the same rural and urban areas in which adequate intake had been found in the national survey. Only 2.5 per cent of 396 children studied showed low or deficient levels. In fact, only one child had a serum level below 10 mg/dl, and in all those with low levels, serum retinol was higher than 15mg/dl (4).
In a limited study done by INCIENSA on 123 pregnant women in a semi-urban area in the outskirts of San Jose, all had serum retinol levels higher than 50, m g/dl. A random sample of 50 lactating women contributing to a breast milk bank showed levels higher than 20 m g/dl in all individual samples. Although these data on the women are incomplete, the findings in preschool children allow us to conclude reasonably that hypovitaminosis-A is no longer a public health problem in Costa Rica. The obvious, immediate question is whether sugar fortification per se was largely responsible for the improvement. To answer that question, the Minister of Health suspended the program of fortification in the second semester of 1980. During the second semester of 1981, a new survey for serum retinol levels was done by the Ministry of Health in the same population of preschool children, showing that of 561 children, none had deficient levels, and only 1.8 per cent had low levels in spite of about one Year without vitamin A fortification of sugar (Minister of Health, personal communication, 1981). A new evaulation is to take place in two years.
It is important to note that the improvement in vitamin A nutritional status was not an isolated finding. Other positive changes in nutritional and health indicators in Costa Rica appeared in the 1970s, changing the disease profile from one classical for underdeveloped countries to one similar to that in the developed nations (5).
By that time, vigorous health programmes, such as community and rural medical care based mainly on auxiliary health care personnel, had gone into effect. These programmes facilitated not only health care but also massive programmes of vaccination and health education. Installation of facilities for proper disposal of excrete was another important undertaking, together with the development of an extended network of lines to supply potable water to most of the country's population. Complementary nutrition programmes for children and pregnant women were reinforced through the so-called Centres of Education and Nutrition and through meals at schools (5).
We tend to believe that the improvement in vitamin A nutrition status in Costa Rica was largely the result of a combination of indirect strategies aimed at improving public health, socio-economic, and educational levels. At the time of the survey in 1966, it was reasonable to recommend fortification. The problem was important, and in fact nobody would have predicted any significant improvement in health problems at that time. However, fortification of sugar was started about nine years after the problem had been identified, at a time when a general improvement in health was beginning to be apparent. Perhaps fortification came too late, and the expense and troubles inherent in the programme could have been avoided.
In principle, a fertile country like Costa Rica should not have to buy premixes of vitamin A at disproportionately high prices, especially at this time of severe economic problems. In spite of the well-known paradox of a higher prevalence of vitamin A deficiency in "ever green countries" (6), in Costa Rica the long-run public health strategy has apparently already succeeded in eradicating vitamin A deficiency (7).
By maintaining the programmes that led to this overall improvement, we believe that our population will be protected from vitamin A deficiency, and perhaps fortification will no longer be necessary.
References
1. Institute of Nutrition of Central America and Panama and the Inter departmental Committee on Nutrition for National Development, Nutritional Evaluation of the Population of Central/ America and Panama. Regional Summary 19651967, DHEW Publication No. (HSM) 72-8120 (Department of Health, Education and Welfare, Washington. D.C., USA, 19721.
2. G. Arroyave, J.R. Aguilar, M. Flores, and M.A. Guzmán, Evaluation of Sugar Fortification with Vitamin A at the National Level, PAHO Scientific Publication No. 38411979).
3. C. Fuscaldo, E. Mohs, and L. Mata, "Lesiones oculares por hipovitaminosis-A y otras causes en niños hospitalizados, 19641975, Acta Méd. Costarricense,, 20: 5 ( 1977 ).
4. Annual/ Report INCIENSA to Ministry of Health, Costa Rica (1979).
5. E. Mohs, "lnfectious Diseases and Health in Costa Rica: The Development of a New Paradigm," Pediat Infect. Dis.. (in press).
6. H.A.P.C. Oomen, "Deficiencia de vitamina A y xeroftalmia y ceguera, in Conocimientos actuales en Nutrición (INCALALAN, 1978), p. 80.
7. G. Arroyave J.C Bauernfeind, J.A. Olson, and B.A. Under. wood, `'Selection of Intervention strategies'', in Guidelines for the Eradication of Vitamin A Deficiency and Xerophthalmia: A Report of the International Vitamin A Consultative Group (IVACG) (Nutrition Foundation, Inc., New York, 1975).
Carlos de Céspedes
Scientific Director
Instituto Costarricense de Investigación y
Enseñanza en Nutrición y Salud (INCIENSA)
Tres Ríos, Costa Rica
Reply to Dr. de Céspedes's letter
Dr. de Céspedes's letter is a timely comment on the recent development in Costa Rica related to the vitamin A nutritional status of the population. However, some added considerations seem important to avoid a one-sided view about a situation that may be somewhat more complex.
In the first place, I believe that the decision made by the Government of Costa Rica in the Year 1980 to suspend the national programme of fortification of sugar with vitamin A was a sound one. In fact, in light of the results of the 1978 dietary surveys that showed that the intake of vitamin A from natural sources by preschool children had become adequate, INCAP supported the interruption of the fortification programme. It also strongly recommended that this decision be followed some two years later by a new dietary and blood serum survey in order to determine whether the higher vitamin A nutritional status attained could be maintained without fortified sugar. For this purpose a special meeting was called by the Minister of Health, requesting INCAP to act as specific adviser.
It is evident from the follow-up surveys that the vitamin A nutritional level in preschool children, and possibly pregnant women, is still adequate. What is risky is to accept this as evidence that sugar fortification did not have any benefit, and that it probably was implemented "too late," resulting in "expense and troubles inherent in the programme" that "could have been avoided." As a scientist, I would consider it just as reasonable, on the basis of the circumstantial evidence available, to suggest that, even in the light of the long-run integrated nutritional programme in Costa Rica, the sugar fortification programme implemented in 1975-1976 served as the determining critical booster to bring the population rapidly to a new, adequate vitamin A status, a status that can now more easily be maintained with diet alone.
Strengthening this probability is the fact that in Guatemala, where the vitamin A sugar fortification programme also began in 1975-1976, but where the dietary and health status of the population at large had not changed for the better, a dramatic improvement in vitamin A nutritional status was shown after only six months to a year of the effective national sugar fortification programme. This was demonstrated by highly significant increases in serum retinol levels in preschool children, retinol in breast-milk, and liver retinol reserves.
In my opinion, the cost of the fortification programme at that time in Costa Rica of about US$300,000 per year was not a disproportionately large expense, and the operation of the programme was so simple that it could hardly have been considered troublesome. To me, both the expenditure and the "trouble" were well justified because: (a} the vitamin A that the population consumed during the years of fortification unquestionably contributed to the adequate vitamin A status now evident; (b) the vitamin A in the sugar went to essentially all of the population regardless of sex or age, while the integrated nutrition plan for dietary improvement in Costa Rica had small children as its principal target. The same dietary survey cited by Dr. de Céspedes showed, in fact, that the children had attained adequate vitamin A dietary status, but the adults within the same families still had clearly inadequate intakes in many instances; (c) if the above were not sufficient, INCAP's promotion of the fortification programme, which fed to its implementation in several Central America countries, awakened the interest and attention of the country to consider a potential specific nutrition problem that needed to be addressed. Even the surveys and analysis of the situation that are at the centre of these letters, as well as the information on the vitamin A nutritional status now available as a useful indicator of improvement, would not be at hand had it not been for the fortification programme at the national level.
I am, however, in agreement with the final statement of Dr. de Céspedes's letter, that if the programmes that led to nutritional improvements in Costa Rica are maintained, fortification should no longer be necessary.
Guillermo Arroyave
Chief, Division of Clinical Biochemistry
Institute of Nutrition of Central
America and Panama
Guatemala City, Guatemala