Previous chapters have thoroughly discussed different types of strategies and interventions aimed at halting the growing obesity epidemic and its consequences. A growing body of literature confirms that effective interventions in a variety of settings, ranging from schools to primary health care centers, have the potential to slow down the progression of obesity. However, the vast majority of childhood obesity prevention and intervention efforts found in the literature have been limited to industrialized countries, predominantly in the United States and Europe. Reported successful interventions—particularly research-based—in the developing world are few and far between.

While important lessons can be drawn from the experiences of industrialized countries in implementing effective prevention efforts, interventions that have worked for developed countries may not necessarily prove effective in the developing world. A myriad of factors including cultural beliefs, social and political systems, and the diverging nutritional reality of low- and middle-income countries call for tailor-made interventions that fit the needs of the unique context of each particular country, region or community. In light of the rising incidence of childhood obesity in the developing world, countries cannot afford to wait any longer. Investing in the identification of the environmental and individual determinants of obesity in each country, and the most effective obesity prevention interventions and strategies to address them early on, can significantly increase the chances of millions of children to live longer and healthier lives.

Childhood obesity trends

A detailed description of international obesity trends and prevalences has been presented in earlier chapters. Nevertheless, it is necessary to give a general overview of the current situation with regards to overweight and obesity trends in the developing world in order to ascertain the need for developing appropriate childhood obesity prevention strategies and interventions.

For over a decade the increasing prevalence of overweight and obesity among all age groups in developing countries has been documented.^1,2 Today, millions of adults and children alike, in Latin America and the Caribbean, the Middle East and North Africa, Asia and Central Europe suffer from obesity.^3–5 For the most part, the rates of obesity are still much higher among the adult population. However, the information currently available on overweight and obesity trends indicates that in many countries the problem is rapidly escalating among the younger populations.

According to WHO, in 2007 nearly 22 million children under the age of 5 years were overweight worldwide; an estimated 16.5 million of them lived in developing countries. Available data from multiple countries on childhood obesity prevalences using the International Obesity Task Force (IOTF)—cut-off points also highlight alarming trends among school-aged children worldwide. For instance, in China the prevalence of childhood overweight among 2–6-year-old children rose from 14.6% to 28.6% and the prevalence of obesity increased over 700% (1.5% to 12.6%) in less than a decade.⁶ In Pakistan a two-fold increase in prevalence of obesity among 5–14-year-old children has been observed in the ten-year span between 1997 and 2007.⁷ Similarly, in Thailand the prevalence of obesity in children 6–12 years of age increased by 27.9% in just two years.⁸ In Latin America, evidence from Chile indicates that from 1987 to 2000 the prevalence of obesity among first grade Chilean boys and girls increased by 161.5% and 138.0%, respectively.³ While according to the Mexican National Health and Nutrition Survey 2006 (NNHS-06) the overall national prevalence of overweight and obesity among Mexican children ages 2–18 increased from 16% in 1999 to 24.3%—a 52% increase in a seven-year period.⁹

Ironically, these countries have struggled to eradicate child hunger and undernutrition for decades. While a few countries, such as Chile, have come close to totally eradicating malnutrition, stunting is still prevalent in most other countries where a growing incidence of obesity has been documented. In turn, as countries progressively undergo rapid economic growth and urbanization they are faced with implications and challenges posed by the coexistence of undernutrition and obesity.

An example of the type of challenges brought about by this phenomenon is the recent finding that children who are undernourished in the first two years of life, but who rapidly gain weight in childhood or adolescence, are at higher risk of developing nutrition-related chronic disease later in life.¹⁰ These children will most likely face the common long-term outcomes of suffering from undernutrition during the critical development period, including shorter adult height and reduced human capital formation, as well as the multiple social, emotional and economic costs associated with obesity later in life. The long term impact of such a cycle being repeated among large numbers of children could be catastrophic. Most notably, the majority of developing countries will not have the capacity to deal with the demands that such a cycle would pose on the medical system.

In view of the multiple short- and long-term negative implications associated with the obesity epidemic facing developing countries around the globe, particularly when the condition is observed at an early age,¹¹ the need for timely and comprehensive interventions is evident. However, in contrast to the recognized availability of effective actions and interventions for the prevention and control of childhood undernutrition globally,^12,13 evidence is lacking on efficacious and effective intervention for the prevention and control of overweight and obesity in both the developed and developing world.

Evidence of interventions

To date, innumerable interventions, programs and initiatives have been developed and implemented to counteract childhood obesity worldwide. Innovative approaches have been undertaken in order to deal with the problem. These have been led by a variety of actors, including parents, teachers, governments, research institutions, not-for-profit organizations and, in many cases, have come about through partnerships and collaborations between some of the actors previously mentioned. Regrettably, recent reviews of the scientific literature, specifically looking at research-based prevention efforts and their effectiveness, point to only two research-based interventions that have taken place in developing countries.^14,15 While a few of the studies in developed countries have dealt with culturally diverse populations, the bulk of the evidence comes from the experience of programs in the United States and the United Kingdom and therefore the implied socio-economic context bears little resemblance to that of developing countries.

It should be noted that other efforts, while not strictly evidence-based interventions, have also been undertaken in developing countries. Considering the information drawn by monitoring systems and surveys, the important role of large-scale community wellness programs and the potential impact of public policies related to nutrition and physical activity, these types of efforts should not be completely disregarded in our examination of the evidence on interventions. Evaluating their results should be considered as part of the process for the design of future interventions or efforts to improve existing efforts. A review and brief description of key efforts identified follows.

School interventions

While there are multiple advantages and disadvantages associated with working at the school level, it is usually asserted that the school environment offers a unique opportunity to reach a large number of children over an extended period of time. Therefore, many consider it to be an optimal setting in which to carry out interventions targeted at children and adolescents (see Chapters 11 and 12). Not surprisingly, the only science-based evidence on efficacy and feasibility of childhood obesity interventions in developing countries comes from research pilots carried out in primary and secondary schools.

Following a longitudinal controlled evaluation study design, an intervention by Kain and colleagues sought to have an impact on the weight status of Chilean children from the 1st grade through to the 8th.¹⁶ The six-month nutrition and physical education intervention program included the implementation of an educational program for children, increased availability of healthier foods at the school kiosks and the implementation of an enhanced physical activity component, along with the provision of the equipment required to support it. Parents and teachers were also considered as part of the intervention efforts and specific activities were undertaken with them to raise awareness about childhood obesity issues. While the study did not show a reduction of BMI at end line, other general improvements in nutrition and physical fitness were observed.

In Thailand, Mo-suwan and colleagues conducted an enhanced physical activity intervention with kindergarten children and monitored the impact of their intervention after six months.¹⁷ Over the course of a seven month intervention period children assigned to the intervention group took part in a structured exercise regimen three times per week in addition to the regular physical education curriculum. The additinal activities carried out included a walk prior to morning classes and dance sessions after naptime. Contrary to the results of the Chilean study period, at the end of the study period the trial came close to showing a significant reduction in BMI. Yet, the post-intervention study revealed a rebound in the participating children’s BMI scores. While the scores did not return to the level of those recorded at baseline they suggest a limited long-term impact of the intervention.

In the near future additional programmatic scientific evidence on school-based interventions in developing countries will be available from two interventions being conducted in Mexico and Brazil at this time. Funded as part of the Healthy Lifestyles Healthy People Obesity Prevention Initiative sponsored by the International Life Sciences Institute (ILSI) and the Pan American Health Organization (PAHO), both projects consist of multi-year community-based interventions aimed at preventing obesity through the modification of diet and physical activity patterns. Both projects, one working with school-aged children ages 8–11 (Mexico) and the other targeting adolescents aged 15–19 years (Brazil), will yield evidence that will allow us begin to fill the existing voids in the scientific literature to informe in the design of effective strategies in the context of everyday conditions. Preliminary results from the study in Mexico^18,19 point key environmental factors at the school level that are potentially responsible for the rapid increase in childhood obesity rates among school-age children in the country. A summary of the results follows.

An initial assessment of the school environment and the physical education program was conducted in 12 public schools in Mexico City. Qualitative and quantitative tools were used to help identify barriers and opportunities in the design and implementation of potential strategies. The focus of the initial assessment was to get a measure of food availability and intake, as well as the physical activity patterns of 4th and 5th grade students during school hours. Based on the IOTF cutt-off points and classification systems the Results from this evaluation revealed that²⁰ —27% of the study population was overweight and 14% was obese (41% combined prevalence). The evaluation of the school environment indicated a wide availability of food high in fat and sugar and low nutritional value and a lack of policies or regulations concerning food sales in and around schools. It was also found that on average children have five opportunities to eat over the course of the 4.5 hours they spend at school every day and that only a small minority of children bring food to eat at school from the home.

Interestingly existing food distribution programs at the school were also found to contribute a significant amount of calories to children’s overall intake while at school. The menu offered as part of the National School Breakfast Program—designed at a time when under-nutrition was still the most pressing nutritional challenge—distributes energy-dense foods, rich in fat and sugar, including flavored sugar-sweetened whole milk, ready-to-eat sugar sweetened cereals or bread, and other products rich in fat and sugar, cookie or dessert that is also high in fat and sugar. In turn, the program offers a limited variety of fruits about once a week. The formative research assessment also revealed that children have limited drink choices. A limited or total lack of access to potable water was documented. Consecuently, for those children who do not bring water from home the only beverage option at the school is the sugar-sweetened beverages available for purchase.

In order to better capture the quality of food available within the school, a system was developed to categorize food based on nutritional value. Healthy foods included fruits, vegetables, low fat dairy products and water. Unhealthy foods were classified into into two groups: foods that would be acceptable if prepared or served differently—for example, baked instead of fried or served in smaller portions—and those that could not be modified and had a low nutritional value. In addition, a food inventory was developed to quantify all food and beverage portions. Based on this evaluation system, only 19% of the foods listed were considered to be healthy, while 81% were classified as unhealthy. Of these, only 31% would be acceptable if modifications were made while 50% were packaged or processed foods with no room for improvement.

Observations of children’s physical activity patterns during physical education class and recess pointed to very low physical activity levels among children. Evaluations conducted using various methodologies including the System for Observing Fitness Instruction Time (SOFIT), pedometers and accelerometers confirmed that children spent most of their time standing. Overall, during PE class children engaged in moderate to vigorous physical activity (MVPA) a total of 11 minutes per week or 26% of the time, two thirds of the time walking and only about one third in vigorous physical activity. During recess, children engaged in MVPA 36.1% of the time or an average of 10.7 minutes per day. The other 77% of the time was spent walking. Overall, the total amount of time spent engaged in physical activity physical was approximately 65 minutes per week and less than 20 minutes was devoted to activities other than walking.

Based on the information collected as part of the initial assessment previously described mentioned above a science-based school intervention was developed with the input of the Secretariat of Education and the school community. Given the breadth of the formative research conducted prior to the design of the intervention it is expected that the program will have a significant impact in food and beverage intake, activity patterns and health and nutrition knowledge. If proven to be successful, it can serve as a concrete model for other countries to follow in the near future.

There are several additional examples of other school-based initiatives, programs and policies likely to have a positive impact in halting the obesity epidemic in developing countries.²¹ However, no published information was found with regards to their impact. For instance, in Brazil it is mandatory for 70% of the foods provided by the school meals program to be basic or minimally processed foods. In the same way, and along with the implementation of more nutrition education and structured physical activity into the school curriculum, notable changes have been made to Chile’s National School Breakfast Program in order to provide more fruits and vegetables as part of the daily offer of food options. In China, the Ministry of Education has been encouraging schools to increase the time allocated for physical activity, while in South Korea dietitians have incorporated the school meals program staff to ensure that more nutritious and well-balanced foods are offered in schools.²²

Community-based initiatives

Communities can play an important role in preventing childhood obesity. Most school-aged children spend a significant number of their waking hours at school; the rest are usually spent in their homes and communities. Agita, a multi-level intervention in an ongoing large-scale community based program to promote physical activity in Brazil is a model intervention for countries to consider when evaluating models for community based initiatives. Many countries have already emulated it including Colombia with Muevete Bogota & Risaralda Activa, Argentina with Amoverse, and Uruguay with Muevete Uruguay.²³ The program’s main objective is to promote an active lifestyle in the general population through a variety of strategies targeting children, adolescents and adults alike. Recent findings suggest that Agita has played an appreciable role in increasing the levels of physical activity and general knowledge about its importance in São Paolo.

Other initiatives with community-wide reach targeting individuals of all ages in developing countries include: the implementation of a health promotion policy with a focus on food, nutrition, physical activity and other risk factors for nutrition-related chronic diseases in Chile,²⁴ a yearly healthy lifestyle campaign to raise awareness about different health issues among the Malaysian population, a variety of large-scale programs on nutrition and physical activity for disease prevention in Cuba and a pilot currently being tried in 32 South Korean health centers to evaluate the impact of providing on-site nutritional services by professional dietitians.²¹ While not specifically a community intervention, another recent initiative with community and nationwide reach are the Beverage Consumption Recommendations for the Mexican Population.²⁵ This initiative, led by the Ministry of Health, is a response to the finding that in Mexico—among the developing countries with the highest rates of obesity among all age groups—beverages contribute a fifth of all calories consumed by Mexicans. The program is in the early stages of its implementation and impact evidence is not yet available.

Monitoring systems

Nutrition monitoring and surveillance is a strategy designed to follow and better understand populations’ nutritional status and consumption patterns, as well as to identify the evolution of nutrition-related conditions over time. It is also a valuable tool at the time of developing any intervention, policy or program related to food and nutrition issues.^26,27 Several countries including China, Cuba, Iran, India, South Africa, South, Brazil, Korea and Thailand, have well-established large-scale monitoring systems that, among other nutrition issues, assess the prevalence of overweight, obesity or nutrition-related chronic diseases.²¹ In Egypt, Malaysia and Mexico, represen tative national comprehensive national nutrition surveys are conducted periodically. By collecting and generating information on a population’s nutritional status over time these data offer a framework to place and assess the effectiveness of any future child hood obesity prevention interventions in developing countries.

Evaluating the evidence

Childhood obesity prevention in the developing world represents a daunting challenge. Given that the variety of barriers in developing interventions are likely to be as diverse as the millions of children that live in low- and middle-income countries and are already afflicted by obesity or risk of developing this condition, providing specific recommendations for potential actions plans is unrealistic. The different interventions and initiatives identified and previously discussed represent a step in the right direction. However, numerous challenges need to be addressed and information gaps need to be filled.

The role of science-based research

The narrow availability of science-based evidence on childhood obesity intervention studies in developing countries precludes the development of well-informed prevention strategies. As a result, most of the initiatives undertaken to date have been implemented without confirmation that they are the most effective or appropriate ones to serve the needs of the populations targeted. Children are influenced by their immediate environment and those individuals who are closest to them. The school, household, community and health care settings are among the most popular sites for conducting all types of child-centered interventions and obesity preventions strategies are not the exception. Evaluating the impact of interventions in all of these settings in developing countries is unquestionably needed. However, the basis for identifying effective long-term strategies is to fully comprehend the nature of the underlying factors accelerating the childhood obesity that is problematic in the developing world and must seek to understand the multifactorial nature of the problem.

For example, issues of safety and accessibility to adequate facilities might disallow some children to participate in physical activity. Similarly, physical and financial barriers are known to prevent families from purchasing nutritious foods such as fruit and vegetables—as well as safe drinking water in cases when potable drinking water is not available—and coerce them to rely on more convenient cheap, non-perishable, calorie-dense products for sustenance. In some societies erroneous perceptions bring about dangerous practices such as overfeeding children or mothers opting out of breastfeeding. Moreover, taking into account information on motivation, eating behaviors and food preferences can be a valuable element in the design of interventions. These types of issues, while not initially considered as research-based studies are designed, are also an essential component of conducting comprehensive solution-oriented scientific research.

Learning by doing

Evidence-based intervention projects can yield information on efficacy or on efficiency. Efficacy refers to the impact of an intervention in a controlled setting; effectiveness refers to the impact of an intervention in a real world setting. Both types of information are valuable and necessary in the process of understanding the issue at stake. However, the rate at which the obesity epidemic is evolving means that many countries cannot afford to wait for the most efficacious programs in childhood obesity prevention to be identified to then implement them. There is a need to conceptualize and implement flexible methodologies that allow for the evaluation of large-scale interventions as they are implemented. Establishing rigorous monitoring and evaluation systems, while allowing for enough flexibility in ongoing programs to make changes as necessary, is a feasible alternative in settings where there is an urgency to intervene.

Sustainability

Effectiveness is not the sole factor determining an intervention’s long-term sustainability. Even when an intervention or pilot project has proved to be effective, a number of additional factors need to be in place in order to ensure long-term sustainability or potential to be scaled-up. Lack of organizational structure and insufficient funding are usually the primary factors that lead to the cessation of otherwise successful nutrition interventions. In many cases, childhood obesity prevention interventions will call for the investment of significant resources to promote and facilitate improved nutrition and physical activity. In the context of limited resources, it is necessary that intervention undertaken among those with low and middle incomes takes into account the cost of upkeeping the initiative devised beyond the initial pilot, particularly when science-based interventions evaluated exclusively for their efficacy, energy and financial resources are invested in programs that will not be sustainable long term. In the interest f serving large numbers of individuals, emphasis should be placed on the evaluation of pilot interventions that have the potential to be sustained even when scaled up at a national level.

Building partnerships is another crucial factor to developing sustainable childhood obesity interventions and prevention efforts in developing countries. Whether carried out at school, community or household level, the relevant key actors need to be involved in the decision-making process regarding the potential strategies to be implemented. Particularly when interventions are carried out at the school and community level, building partnerships among public agencies, community members, industry and other constituents is likely to bring about a supportive environment in which any program will have better odds of having a positive impact.

The double-burden challenge

One of the most complex and inevitable challenges faced by countries developing strategies to face the growing rates of childhood obesity where undernutrition prevails is working around existing nutrition programs. One of the universal goals of most nutritional assistance and supplementary feeding programs in developing countries has been to promote normal growth and development in children. Through the provision of energy-rich foods such as whole milk and fortified cereals at the household and school level these programs ensure that children meet their daily caloric needs. However, among populations experiencing nutrition transition, and where some benefici-aries already meet the recommended daily energy allowance, universal feeding programs are likely to promote obesity.

As obesity prevention strategies are developed in developing countries, the role of supplementary nutrition programs must not be overlooked. While they are likely to continue to be necessary for segments of the population, their structure must respond to the changing nutritional reality of transitioning countries. Failing to do so will inevitably result in the execution of programs that have conflicting objectives simultaneously. Therefore, particularly in rapidly developing countries and urban areas, existing pro-poor nutrition programs should begin to identify strategies by which children continue to receive an adequate nutrition while at the same time avoiding the risk of their becoming overweight. Specifically, in geographical areas where under- and overnutrition are observed, potential strategies include the revision of the types and quality of foods offered as part of school breakfasts and lunch program menus (i.e. providing reduced fat milk and including more fruit and vegetables), a revision of national feeding practices guidelines and recommendations, and the modification of targeting mechanisms of program benefit distribution.

Conclusion

The prevalence of unhealthy weight in children is increasing in developing countries at a high rate. The potentially devastating long-term consequences of this epidemic on children’s quality of life call for immediate actions and policies aimed at the prevention and control of these conditions. Although there is consensus that the caloric energy imbalance that has resulted from the simultaneous increase in consumption and decrease in levels of activity is a determining factor in the problem, the relative importance of more distal factors is still contested. Hence, the need to promote physical activity and healthy diets in a variety of different settings, particular those that children are influenced by or take part in, such as the home, school and community, is widely accepted.

At a global level, increasing children’s physical activity levels and reducing energy intake will require environmental changes so that the option to make healthy choices is available. Only in environments where healthy choices are an option will communication strategies to inform and motivate reach their full potential. Producing effective interventions, particularly in developing countries, poses countless logistical challenges that require careful examination. Yet, in many cases the nature of the problem does not afford countries the luxury of conducting preliminary research. Programs and interventions need to be developed and implemented without further delay and based on the best available evidence. The key to their success lies in the implementation of thoughtful monitoring, evaluation plans and malleable structures. Only then will we be able to generate evidence-based literature to learn from—evidence that bravely documents failures, is unassuming about successes and allows all of us to draw lessons from a wide range of experiences.

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