A Vision for Nutritional Research for the Latin American Region

Introduction

Latin America is an extension in the Western Hemisphere defined by the official languages of the nations and territories of Spanish or Portuguese; this bespeaks of a history of colonization by Spain or Portugal. Latin America extends in length from +32.5 north latitude at Tijuana, Mexico, to −55.5 south latitude in southern Patagonia, a total of 88 latitude degree units. The geological and topographical variation of Latin America equals or exceeds the African and Asian continents.

The Latin American population is estimated to be 655 million persons, living in a land area of 19 million square kilometers. It is ethnically diverse. Pre-Colombian inhabitants were Amerindian indigenous peoples originating and dispersing from the crossing of the Bering Strait in 15 000 ad. Today, they extend from the plains of northern Mexico to the Amazonian basin with descendants of the great civilizations of the Aztecs and Maya in Meso-America and of the Inca in the Andean region. Since the conquest, joining the original indigenous populations since have been descendants of the original Iberian colonists, along with Africans imported as slaves, concentrated predominantly in Caribbean and Brazilian climes. Representatives from countries of Europe and the Middle East are among the more recent inhabitants of the region. The extent of urbanization in Latin America runs far in advance of Africa and Asia, with 80% of Latin Americans living in urban areas. Only Guatemala and Honduras have a majority rural population in the 21st century.

The original major staple crops were maize in the Meso-American area and potatoes in the Andes. Yuca, or cassava, extended throughout the region. Corn and potatoes were transplanted, along with coffee and cacao, to the Old World, while wheat and rice were introduced from the Eastern Hemisphere. Currently, the major staple food in the southern cone is wheat. Some forms of legumes are part of the diet in all parts of the region. Local and subregional cuisines vary widely across the region depending upon the suitability of the terrain to the raising of different crops and horticultural items, and the herding of livestock, as well as the abundance of wild plants for forage and fauna from hunting and fishing. Not all that is edible is eaten; especially among indigenous and more traditional rural groups, there exist deeply entrenched taboos and food beliefs. After the approval of the free-trade pacts among the United States, Canada, and Mexico in the North American Free Trade Agreement in 1992 and between the United States and the Central American nations and the Dominican Republic in the Central American Free Trade Agreement in and around 2006 to 2009, in 2018 the Comprehensive and Progressive Agreement for Trans-Pacific Partnership was signed by 11 countries: Australia, Brunei, Canada, Chile, Japan, Malaysia, Mexico, New Zealand, Peru, Singapore, and Vietnam. These treaties permitted the tariff-free commerce of prepared food and beverage items among the signatory countries, most importantly opening up the exposure on the Latin American side of commercial foods from a number of countries at prices competitive with local industry. There are also bilateral free trade agreements such that signed in 2004 between Chile and the United States. The common market of the southern countries of South America (Argentina, Chile, Paraguay, and Uruguay) was signed in 1991 as a free trade treaty among the nations. The similar food habits and production of these countries made it less disruptive of the offering of products than the treaties with the United States in the northern sector of Latin America.

Where We Have Come in the Region

Nutritional science, both clinical and public health, originated in the region shortly after the end of World War II. In 1949, the Pan American Health Organization founded the Institute of Nutrition of Central America and Panama (INCAP) under the direction of Nevin Scrimshaw. ¹ The mantle of nutrition and training throughout the region, however, was taken up mainly by university departments, with an assortment of specialized institutions, notably in Chile, Cuba, Colombia, and Peru. The persons listed in Table 1 illustrate what could be considered the classic contributors to nutrition and food science in the region, who brought their findings and institutions into an international context. Several, notably Scrimshaw and Roberts (United States), Jaffé (Germany), Tripathy (India), and Bengoa (Basque country of Spain), were not native to the region. Thus, a first generation of leaders in nutrition and food technology had to develop de novo out of their background professional formation. Not surprising, the majority of the early leadership came from the medical community, from pediatricians, and from other physicians across the region.

Table 1.

Major and Notable Figures in the Emergence of Nutrition and Food Sciences in Latin America.

Country	Institution	Classical Figures and Contributors
Chile	Institute of Nutrition and Food Technology (INTA), Santiago	Fernando Monckeberg
Brazil	University of Sao Paolo, Ribeirao Prieto	Eduardo Dutra de Oliveira
	Brazilian Nutrition Society, Rio de Janeiro	Walter J. Santos
	Federal University of Pernambuco, Recife	Hernando Flores
Colombia	Colombian, Family Welfare Institute, Bogota	Roberto Rueda-Williamson
	University of the Valle de Cauca, Cali	Tripathy, Luis Mayoral
Cuba	Institute of Nutrition and Food Hygiene, Havana	Manuel Amador
Guatemala	Institute of Nutrition of Central America and Panama (INCAP), Guatemala City	Nevin Scrimshaw, Ricardo Bressani, Guillermo Arroyave, Fernando Viteri
Mexico	Children’s Hospital, Mexico City	Federico Gómez, R. Ramos-Galván, Joaquín Cravioto, Silvestre Frenk
	National Institute of Nutrition of Mexico, Mexico City	Salvador Zubirán, Adolfo Chávez, Hector Bourges
Peru	Grace Department of Research, British American Hospital, Lima	George Graham, Juan Baertl, Ángel Cordano
Puerto Rico	University of Puerto Rico, San Juan	Lydia J. Roberts
Venezuela	National Institute of Nutrition, Caracas	Werner Jaffé
	Central University Medical School, Caracas	Miguel Layrisse
	CAVENDES Foundation, Caracas	José María Bengoa

The Latin American Society of Nutrition was founded 6 decades ago and has held triennial congresses with a rotating presidency since that time. These have helped to integrate scientist from across the region. Additionally, 2 critical International Congresses on Nutrition (ICN) were held in the region in the 1970s: the 9th Congress in 1972 in Mexico City, hosted by Adolfo Chavez, and in 1978, the 11th Congress in 1978 in Rio de Janeiro, hosted by Walter J. Santos. The respective 2000 attendees from 66 countries at the former and 3500 from 92 countries at the latter introduced much of the international nutrition community to the nature and scientific interests of Latin America. It would be almost another 2 decades, however, before the ICN would revisit the region, in 2017, in Buenos Aires, for 3000 delegates.

It can be honestly concluded that the nature of problems of undernutrition proved to be roughly similar and parallel across the 3 major developing regions, not that the early research from Africa, Asia, and Latin America can be compared. Since clinically trained individuals predominated in the regional community, those nutritional conditions with a clinical (symptomatic) presentation of manifestation would attract the greatest attention. Indeed, severe protein-energy malnutrition (PEM), endemic goiter, and nutritional anemia would become the most studied topics. Vitamin A would make a second tier; it has been pursued more at a survey and population level due to its more muted clinical presentation in Latin America. ^2,3 Most of the early leaders mentioned in Table 1 were distinguished for addressing one or another—and often several—of the aforementioned deficiencies.

Major contribution to the recognition and treatment of PEM came from the Latin American region, from the establishment of kwashiorkor in the Western Hemisphere ⁴ to its classification standards, derived in the Children’s Hospital of Mexico City by Gómez et al, ⁵ to careful studies on feeding and rehabilitation in Guatemala, ⁶ Chile, ⁷ and Peru. ⁸ This included the development of a vegetable-based product, INCAParina, developed by Bressani and Elías. ⁹ This was a model for similar products around the world. The secondary consequences of PEM for cognitive development were most aggressively pursued in Latin America, most notable by Cravioto in Mexico ^10,11 but also by field studies in Bogota, Colombia, ¹² and Eastern Guatemala. ¹³ The seeds of detection of lesser grades of PEM at a population level by anthropometry were developed in Guatemala ¹⁴ and Colombia. ¹⁵ The PEM was addressed robustly in the region, but it was never a public health problem of the magnitude of the other affected continents.

With respect to goiter, global benefits were derived from the documentation that the more stable iodine salt, potassium iodate, was as effective as the effervescent potassium iodide in table salt fortification to eliminate the condition. ¹⁶ Iodate would become the standard where table salt was coarse and humid.

Anemia was considered to be primarily of iron deficiency origin in the region. Miguel Layrisse recognized the endemicity of profound anemia due to chronic blood loss among hookworm-infected sugarcane workers on the Venezuelan coast. It was in an outstanding gesture of international collaboration that the bioavailability of iron from different food and medicinal sources of iron could be assessed. ¹⁷ It was also within the region, with studies in Chile ¹⁸ and Costa Rica, ¹⁹ that the causal association of early iron-deficiency anemia with permanent cognitive performance was documented. The search for solutions to redress anemia has been explored in the region at the level of fortification of sugar, ²⁰ milk, ²¹ and drinking water. ²² The Demographic and Health Surveys across the region are currently showing a reduction in anemia rates in young children and adult women.

Fortification for another endemic deficiency was advanced from the region, the fortification of table sugar with vitamin A. Hypovitaminosis A was endemic in Guatemala and confirmed by low circulating retinol concentrations. Arroyave and coworkers ²³ demonstrated the reversal of both intake and biochemical deficits during the initial national fortification implementation in Guatemala. The measure is mandatory across the countries of the Central American isthmus. ²⁴

It has been established that riboflavin ²⁵ and vitamin B₁₂ ²⁶ deficiencies can be endemic in the Meso-American area, but little public health response has yet been mobilized. Copper deficiency is a rare and generally iatrogenic condition. One of the first descriptions of its existence and manifestations in humans came from Lima, Peru. ²⁷ An example of a preventive therapeutical approach worth mentioning is the multiple micronutrient fortification program implemented at the national level in Chile in 1999 thanks to the work of Castillo-Duran, ²⁸ Ruz, ²⁹ and Hertrampf. ³⁰ The product, the fortified milk “purita” contained additional amounts of iron, zinc, copper, and ascorbic acid. Perhaps the most important feature of the 7 decade of history in nutrition and food science from Latin America is that it has established important associations, and general insights about solutions, which are applicable beyond the region as discussed above.

Two additional instances are most notable. In 1987, the CAVENDES Foundation of Venezuela convened a conclave of Latin American nutritionists to develop an alternative and more practical approach to operationalizing nutrient requirements. It was a food-based approach, anchored around nutrient density and the differential requirements across members of households. ³¹ Although it is a monumental conceptual achievement, it has yet to be widely adopted. In 1992, findings from a longitudinal follow-up of the protein versus calorie (atole vs fresco) intervention in Eastern Guatemala were compiled for presentation. ³² It was clear that beneficial effects on growth and health from the intervention were dependent on a specific window of exposure to the supplement, namely, up to 2 years of age. This observation would become the basis 2 decades later for the “First 1000 Days” window of opportunity concept adopted by the US Agency for International Development.

Emerging Insights

There has been a pause in interest in protein nutrition in Latin America, although micronutrient nutrition has evolved as a topic. Meanwhile, the panorama of micronutrients is changing. Diverse evidence from national surveys shows a steady reduction in hypovitaminosis A and anemia, and with regard to these, it is in a superior situation as a region compared to Asia and Africa.

The situation with regard to other micronutrients is less resolved. For example, recent findings from the region have cast uncertainties on the importance of human zinc deficiency as a relevant public health or clinical problem. Zinc supplementation failed to enhance growth in the second semester of life in rural Guatemalan infants. ³³ Moreover, the intestine seems better able to adapt to extraction of zinc from phytate-rich diets than had previously been considered. ³⁴ No evidence for adjunctive effects on the control of type II diabetes was found in an intervention trial in Santiago, Chile. ³⁵ On the other hand, zinc absorption is dramatically and irreversibly reduced after bariatric surgery. ³⁶ At the same time, however, botanical and agronomic efforts for biofortification are emerging to increase the content of zinc, as well as iron, in the crops of the region. ^{37 -39} Relevant information in the area of biofortification of edible plants regarding soil characteristics, ⁴⁰ demonstrated efficacy, ⁴¹ and regulatory frameworks ⁴² is making the approach more viable in agronomy.

Nutritional deficiencies that have not been fully explored are being documented in Latin America. For instance, because of the tropical latitudes of the majority of the region, it was considered a priori that vitamin D would not be a problem. Brito et al, ⁴³ however, have documented that vitamin D intakes and circulating levels have been deficient or insufficient in almost all sites in Latin America and the Caribbean in which they have been investigated. Notable is vitamin D status evidence from a nationally representative sample in a Mexican child survey, showing widespread deficiency and insufficiency. ⁴⁴ Essential fatty acids of the omega-3 variety represent another nutrient of emerging concern for the region; in Guatemala, both low dietary intakes ⁴⁵ and red cell membrane deficiency ⁴⁶ of docosahexaenoic acid have been documented.

Lactation biology and micronutrients have been joined in Latin America as matter of concern. Findings from the region on micronutrient contents of human milk are having global implications. Research from the region is indicating lower micronutrient intakes of both B-complex vitamins ⁴⁷ and minerals ⁴⁸ than the adequate intakes.

It is safe to conclude that the focus of nutritional sciences has turned away from deficiency states to the consequences of excess consumption in recent years in the Latin American region. Overnutrition, reflected as excess weight, has vastly surpassed undernutrition, reflected as the aforementioned micronutrient undernutrition, in the Latin American expression of the dual burden of malnutrition. It has been estimated that overweight and obesity currently affect between 20% and 25% of children and adolescents in the region, ⁴⁹ with vastly divergent prevalence across nations. The US Fogarty International Center of the National Institutes of Health invested in a conclave to spur research and policy to confront the ascending trend. ^50,51

Mexico can be considered to some extent, both in its excess weight prevalence and its investigative and policy response to be an epicenter for the region and the focus for a case analysis. Sugar-sweetened beverages (SSBs) have been isolated as a major potential driver of overweight conditions. ⁵² Excessive consumption of sugar and SSB was identified as a major contributor to energy imbalance across the Mexican population. ⁵³ Notably, international data are inconsistent on the effects of early SSB consumption and obesity later in childhood. ⁵⁴ Whether taxation of SSB is a disincentive is being addressed in Mexico. A 1 peso per liter tax on SSB went into effect on January 1, 2014. Surveillance of thousands of households from before implementation until the end of 2014 at the levels of both in-store purchase and consumption of drinks showed significant declines. ^55,56

In a broader context, Mexico has general dietary recommendations for selection of food groups in nutritional standards for Mexican schools. In a national survey, a low percentage of the population met recommendations, whereas upward of half of the respondents exceeded allowances for SSB, high saturated fat and/or added sugar products, and processed meats. ⁵⁷ A mandatory code of standards for health of foods sold in Mexican schools was adopted in 2011; compliance with nutritional standards reached a scant 23%. Only 18% of the children consumed a healthy snack. ⁵⁸

A similarly prescriptive approach toward a healthy dietary fare, but applied across all segments and ages in all populations, has been spearheaded with an impetus from Brazil over most of the past decade. In 2010, Monteiro and colleagues proposed a 3-group classification system, introducing the term “ultra-processed” for various manufactured commercial food and beverages. ⁵⁹ The fabrication of these foods was for motivations of lower price, attractive color and taste, and preservation properties, but the addition and omission of ingredients has been posed as detrimental to nutrition and health. Consumption of ultra-processed foods has been explored in greater depth in Brazil. ^{60 -63} Elsewhere, in Chile, an analysis of ultra-processed food consumption has been published more recently. ⁶⁴

With the passage of time and experience gained, the originators tweaked the classification, evolving into the NOVA eating guidelines, a food classification based on the nature, extent, and purpose of food processing that places foodstuffs into 4 groups. ^65,66 The authors comment, “It specifies which foods belong in which group and provides precise definitions of the types of processing underlying each group.” The revised classification levels in NOVA are outlined in Table 2. The term “ultra-processed” has been used in editorials in scientific journals and in documents of the UN agencies. This classification is not without its detractors and has been taken to task in more than one critical commentary. ^67,68

Table 2.

Group-Wise Classification of Foods According to the Revised NOVA Guidelines.

– Group 1: Unprocessed or minimally processed foods – Group 2: Processed culinary ingredients – Group 3: Processed foods – Group 4: Ultra-processed foods

Neeha and Kinth ⁶⁹ define nutrigenomics as “an emerging field that tends to unfold the role of nutrition on gene expression, which brings together the science of bioinformatics, nutrition, molecular biology, genomics, epidemiology, and molecular medicine.” On the other hand, the closely related term “nutrigenetics” refers to the effect of genetic variation on dietary response and nutrient metabolism and action. ⁷⁰ Over the last decade, genomics has move from single-nucleotide polymorphisms as the central tool to genome-wide association (GWA), representing an enormous advance. Some see the potential for nutrigenomics to help solve the overweight and poor diet dilemmas firmly recognized in Latin America (above). ⁷¹ Some examples of research in the region in this area are the study by Smith et al ⁷² in adults of Puerto Rican origin, in whom a specific variant in the hepatic enzyme, lipase, governed levels of a circulating lipid with implications for atherogenesis risk. Similarly, the degree of European admixture in Bostonians born in Puerto Rico was a negative determinant of bone mineral density ⁷³

Future Projections

As urbanization and the nutrition transition in diet is making much of Latin America similar in lifestyle conditions to that in North America and Europe, the investigation of dietary risk of obesity and metabolic and chronic diseases may be informed at the population level by discoveries in these high-income regions. Our diet and disease inquiry can build on comparative literature, with adaptation of promising measures for weight control from comparable ecological settings. Even better would be affiliation in collaborative networks that link Latin America with North America and Europe.

This comes, however, with the important caveat of ethnic specificity and adaptation in the Latin American region. With all of many superficial similarities with other urbanized nations, the genes of our region may be factors of which to take account. As such, the expansion of nutrigenomics/nutrigenetics technology will be a requisite. This will advance rapidly with the emerging facility to perform GWA assays and to assort, analyze, and interpret it. Two bioethical issues challenge the wider and deeper application of GWA. The first is related to justice and equivalent access across society, insofar as the original intention was to further individualized, personal health. ^74,75 A consortium of nutrigenomics collaborators, however, set out a proposition and agenda for the application of nutrigenomics to reduce disparities among the more and less powerful and affluent members of societies. ⁷⁶ This socialization of GWA should be the way forward in Latin America. With such a resolve, however, the issue of autonomy of the research subjects comes into play. To the extent that schooling and linguistic and scientific literacy can be limited, especially among indigenous groups, the informed consent procedures for GWA must be adapted within cultural contexts and levels of schooling and the anonymity of subjects and groups needs to be securely guarded. ^77,78

The other ‘Omics technologies have equal value to the nutritional questions in the future of Latin America. Fortunately, they are less bioethically challenged. The intestinal microbiome is centrally relevant to both overweight and underweight status. ^79,80 It has been elegantly exploited in a cohort of Finnish pregnant women ⁸¹ to reveal its supporting nature in gestation; there is little comparable application in the region. Microbiomics can be applied to breast milk as well, with potential insights for child growth and development. ^82,83 All of the members of the ‘Omics, including transcriptomics, proteomics, metabolomics, lipidomics, and so on, should be embraced and applied in future nutrition research by our community.

In a related, technology-dependent domain, the application of “big data” has been outlined, that is, large population sets to advance knowledge, specifically in the domain of nutritional biological anthropology ⁸⁴ and the potential for new knowledge. This challenges the region to create and maintain surveys with reliable and high-quality data. For the big data agenda in Latin America, public health nutritionists must make strategic alliances with the appropriate computing facilities, including advanced software, and the technical professionals who write and run them. Complementing massive cross-sectional data should be longitudinal studies of diverse cohorts throughout the region that are creatively conceived and carefully managed. Individuals followed now through 3 generations from 2 Latin American settings, Eastern Guatemala and Southern Brazil, are part of the cohort associated with 3 other sites (Philippines, India, and South Africa) in the COHORTS consortium. ⁸⁵

Although the fundamentals of the bidirectional interaction of nutrition and infection were enunciated by Scrimshaw et al ⁸⁶ decades ago, this has been ignored with respect to the emerging viral diseases of the Americas, for example, dengue fever, Zika, and chikungunya. Whether nutritional factors influence susceptibility and the consequences of infection merit inquiry. Some pioneering work in individuals infected with the dengue virus was performed in Guatemala, ^87,88 but expanded work across emerging viral fevers with modern techniques is badly needed.

The duration and exclusivity of breastfeeding throughout the Latin American region is estimated to be of a rather low order. ⁸⁹ The importance of exclusive breastfeeding is likely to be an enduring truism. Doubts about the universality of its nutritional adequacy must be addressed, ⁹⁰ and promotional programs to maintain the practice in the dominantly urban environment should be encouraged.

One would hope to see the advance of studies demonstrating improvement in nutritional status through consumption of biofortified foods, potentially applying emerging genetic techniques. Currently, crossbreeding (hybridization) is the favored approach to enriching edible plants with minerals and vitamins due to popular and official skepticism and aversion to genetically modified organisms. The emerging technique of gene editing, in which foreign genes are not introduced, but rather genes are tailored in their functions, may prove a potent and exceptional alternative. The capacity of gene editing for biofortification is being demonstrated. ^{91 -94}

On the policy front, the future should look to the past on reviving, modernizing, and promoting the seminal concept of the CAVENDES Foundation for the approach to food-based guidelines. ³¹ The basic tenet of the Bengoa group’s solution was that the composite daily fare, when consumed according to each individual’s energy needs, should provide age-appropriate requirements. This would be achieved if every food and beverage item had covered the nutrient density of protein and all micronutrients such that someone with 2000 kcal energy requirement would meet needs of all nutrients. What needs to be realized is that an ever-increasing portion of individuals’ intake will be consumed outside the home. The policy implication is that efforts would be made to groom the food supply as a whole, whether prepared at home, served from commercial products, or ordered in food outlets (restaurants, cafeterias, street-food kiosks, fast-food establishments, etc), at standard nutrient density. This grooming would begin with growing nutrient-rich varieties of plants and animals and supporting with biofortification and fortification during processing. Moreover, to the extent possible, the healthy eating guidelines for sustainability of both the population’s diet and the ecology of the planet are to be followed, as in the Lancet report, Food in the Anthropocene: the EAT–Lancet Commission on healthy diets from sustainable food systems. ⁹⁵

Conclusions

Nutritional well-being is a constant (battle) of accessing and consuming sufficient nutritious food while maintaining a state of general health that allows the nutrients to be absorbed, retained, and utilized. If indeed the paradigm is still a dual burden of malnutrition, our region has mitigated much of low body size and micronutrient deficiency. Rather, the challenges from excess body mass and consumption of negative nutrients loom larger. The fact that obesity and overweight are the more pressing nutritional problems in the area are overt testimony to the general access of more than sufficient calories for energy balance from foods of national production or imports. We must be vigilant that the diet of abundant calories has a nutrient density to satisfy vitamin and mineral needs, especially if the efforts to combat excess weight reduce the net consumption of foods and beverages. The ecological and environmental challenges, however, are a major incognito for Latin America, as with all regions. These include deforestation and exhaustion of arable lands; rising oceanic levels affecting the habitability of islands and coastal plains; and warming of the waters, soil, and atmosphere with the consequent challenge to the health and stability of edible flora and fauna. As we are clearly subject to unpredictable changes in the food system from these pending disruptive phenomena, the technical solutions and the professionals required to devise and manage them, including in the implications for human nutrition, will need an emerging and adaptive training and role in our community.