Abstract

Objectives: This paper aims to present and analyze data on malnourished children from low socioeconomic (SES) status who experience cognitive deficits.  This paper will also provide ideas for interventions to decrease the number of malnourished children in developing countries. 

Methods: The data in this paper is from various other research papers. The main engines for finding these papers are PubMed and Google Scholar.

Results: Children who face low socioeconomic status and are from developing countries are more likely to be malnourished. Uneducated parents and parents who receive low wages have a greater chance of having undernourished children. Malnourished children perform worse in school than those who had adequate nourishment. Undernourished children will continue to face impaired cognitive function in adulthood. 

Discussion: In order to decrease the number of malnourished children in developing countries, interventions can be done. Literature supports that children who struggle with malnourishment have both physical and cognitive deficiencies such as stunting and poor school performance. 

Introduction

Malnutrition is a severe condition that accounts for approximately 45% of deaths among children under five in developing countries (World Health Organization, 2021). Moreover, malnutrition is significantly linked to children from low to middle-income families. Children from families of low socioeconomic status are more likely to be undernourished since their parents may not have the education or money needed to feed their children healthy and nutritious foods from each food group. Furthermore, malnutrition can be caused by mothers who aren’t feeding themselves the adequate foods that are essential for childhood development while the child is in utero. In any case, malnutrition is commonly seen in developing countries where there are scarce resources.

The results of malnutrition include stunting, wasting, and iron deficiency anemia. These consequences of malnutrition have a significant impact on child development at an early age and often lead to several long-term side effects. Stunting is when children have low height-for-age, this differs from wasting which is when a child has low weight-for-height. Iron deficiency anemia is also a type of malnutrition where children lack the appropriate amount of iron. In all of these types of malnutrition, the children are not getting the suitable amount of food they should receive. Due to this, children are not able to develop appropriately, which leads to impaired cognitive abilities. In addition, malnutrition is often linked to poorer school performance, likely due to impaired cognitive abilities. As mentioned above, these consequences of malnutrition continue into adulthood. These consequences emphasize the urgency for interventions to help these children.  

Malnutrition in children is a topic that many researchers have explored, and some organizations are working to mitigate the rates of malnutrition in children across the globe. This paper will evaluate existing literature to discuss childhood malnutrition factors that lead to cognitive, developmental, and physical delays. We will then discuss the long-term impact of impaired cognitive ability in adulthood. Lastly, we will discuss interventions to improve access to nutritious and healthy food for children with the hopes that it will have lasting impacts. This paper will add to the current literature on the topic of malnourished children.

Stunting

Stunting, a condition in which children are unable to meet a sufficient height for their age, is a major indicator of malnutrition. This finding is more prevalent in developing countries where there seems to be an association between stunting, poor nutrition, and infectious disease. Globally, data indicates that the prevalence of stunting in children that are less than five years old is 26% (Sulaiman et al., 2018). Specifically, stunting is more commonly found in low-resource  countries. India contains the most stunted children, statistically, as a study proved that the number of children stunted in India was 47.14% in comparison to the number of children stunted in other developing countries at 39.90% (Verma & Prasad, 2021). A systematic review that included 15 studies demonstrated that 1/3 of children under the age of 5 were stunted. In this study, Pakistan, Guatemala, Bangladesh, and Burundi found that 56%, 55%, 48%, and 45%, respectively, of children who lived in urban and poor clusters, were stunted. Comparatively, when looking at children who had lived in the same developing country but in poor versus non-poor environments, the ones who lived in poor environments had greater odds of being stunted (Assaf & Juan, 2020). Specifically, children that come from families of low SES are more likely to suffer from stunting which is in relation to malnutrition. 

 Stunting has also been linked to the highest education level of a child’s parents. In a study conducted in China, it was found that children of mothers with lower education levels were more likely to be stunted than those of mothers with a higher level of education. The study hypothesized that the children of the mothers who had lower education were more likely to be stunted because those mothers were more likely to make a small salary and be uneducated about healthy feeding practices (Liu et al., 2021). Statistically, a study found that the children of mothers that had education below primary level had 2.93 more odds of being stunted than children whose mothers had minimum secondary education (Bhattacharyya et al., 2021). Not only was the mother’s education connected to stunting, but other maternal factors were also linked to the increased likelihood of stunting. For example, if mothers were over eighteen at marriage and visited antenatal clinics more than three times during their pregnancy, there was a smaller chance that the child would be stunted. The mother's height was also significantly associated with stunting, as mothers with shorter statures were more likely to have a stunted child (Khan et al., 2019). The research indicates that several maternal factors impact a child's likelihood of being stunted; these factors become more complex when considering the lack of resources that many families face in underdeveloped communities. 

Children who were stunted have a greater chance of having a low IQ. Children in China from the ages of nine to eleven that were stunted and had intestinal worms had low process IQ and low memory IQ. These children being tested went to boarding schools which had a significant association with stunting and low memory IQ as the living and food conditions that the rural boarding schools provided were worse than the ones in their homes (Guan & Han, 2019). Through the use of MRIs in the urban area of Bangladesh, it has been proven that stunting has a high effect on white matter regions of the brain, which is also associated with poor childhood development (Turesky et al., 2021). In fact, a study comparing children from the age of three to eleven demonstrates how white matter is related to poorer cognitive function. Findings showed that there was a direct correlation between stunting with verbal IQ and performance IQ in both children that were three and eleven years old. White matter regions are connected with performance IQ and not verbal IQ (Venables & Raine 2016). The understanding that worse performance IQ was observed in both eleven-year-olds and three-year-olds is essential as this shows the link between stunting and its effect on white matter areas of the brain. This demonstrates a potential area of impact with lasting consequences that stunted children may have to deal with later in life. Their lack of white matter development as a child will affect them as they grow older since they have a greater chance of having a poorer IQ and lower cognitive development. Furthermore, the association of white matter regions of the brain is negatively impacted by stunting proves that poor brain development linked to stunting can be linked to lower IQ. 

Relating to how stunting is prevalent in lower resource areas, there is room for intervention to be done to lower the number of these children who are stunted. Firstly, as the mother's level of education is commonly associated with the likelihood of their children being stunted, there can be educational seminars for up and incoming mothers on how to properly feed themselves during pregnancy. These seminars can also educate them on what foods and nutrients they need to feed their children. It has been found that many mothers simply do not understand that they are not providing their children with the nutrients that they need. So, having educators go to places with high stunting rates in underdeveloped countries would be beneficial as they could teach mothers proper feeding practices. Another area of intervention is to support the already stunted children going to school. As these children have lower IQs and lower cognitive function, it may be best to modify the curriculum in high-stunted areas that allow them to learn at a slower pace or have more time with the teachers to understand the information they are being taught. Teaching stunted children at a slower rate when they are younger can teach them good study habits and learning skills that they can use when they’re older. Another area to consider is creating programs that provide adequate food to children in poverty. By doing this, these children will have a more stable course to healthy foods that are needed for proper development.

Anemia

Anemia can be defined as the reduction in hemoglobin concentration, red-cell count, or packed-cell volume, as well as the impairment in meeting the oxygen demands of tissues; these issues are connected to genetics, infectious disease, and nutrition (Balarajan et al., 2011).  In relation to anemia, iron deficiency is observed when the intake of total or bioavailable iron is inadequate to meet iron demands or compensate for increased losses (Balarajan et al., 2011). Hemoglobin values are commonly used to indicate iron deficiency anemia; however, hemoglobin concentrations do not show the specificity of iron status. Therefore, hemoglobin concentrations can be used as an indicator of iron deficiency, but it is most effective when the iron deficiency is high, which leads to concentrations of serum ferritin and transferrin receptors being a better way to indicate iron levels (Balarajan et al., 2011)(Schneider et al., 2005). For the purpose of this paper, iron deficiency and iron deficiency anemia will be discussed congruently. 

In children, it is typical for anemia and iron deficiency to be linked to the prenatal health of their mothers and the children when they are born. Children with low birth weight are expected to be iron deficient and anemic due to their bodies having smaller space to store iron which subsequently leads to catch-up of red blood cell growth (Schneider et al., 2005). As pregnancy progresses, there is an increased demand for iron. If the women are not getting the sufficient amount of iron needed, they will be more prone to acquiring an iron deficiency which could negatively affect the development of their child (Mireku et al., 2016). The demand for iron in pregnant women is most clearly seen as an expansion of red-cell mass, and the maintenance of the maternal-placental-fetal unit results in the need for more iron (Balarajan et al., 2011). Anemia during pregnancy is common in developing countries as these countries have high numbers of births in short intervals without proper access to antenatal care or supplementation (Balarajan et al., 2011).  Iron plays a vital role in the development of the fetus as it is involved in the appropriate myelination of white matter cerebellar folds, hippocampus development, and neurotransmitter synthesis, which are necessary for a child's brain function (Mireku et al., 2016). So, the amount of iron that a mother has during pregnancy is key to a child's brain development, as insufficient amounts of iron in a mother can interfere with the development of many parts of the brain. Furthermore, it is commonly seen that mothers in developing countries do not have access to the proper supplementations or do not have the education to determine what nutrients they need to have a healthy child. Therefore, these children are more prone to iron deficiency and anemia when their mothers do not get the proper amount of iron needed for healthy childhood development. 

Children who suffer from anemia or iron deficiencies are less likely to perform well in school or during tests. One study observed children, from six to sixteen years of age, with an iron deficiency, iron deficiency anemia, and children without iron deficiencies in order to compare their performance on various tests. There was a significant difference shown in math scores between children with low iron levels and those with normal iron levels. Those who were iron deficient scored lower than those who were not. This is demonstrated by those who had iron deficiencies with and without anemia showing significantly worse scores, especially in math, in comparison to those with normal iron levels (Halterman et al., 2001).  Furthermore, it was found that iron deficiency without anemia was more prevalent than iron deficiency with anemia. This is believed to be because iron utilized in the central nervous system decreases before the depletion of iron needed for red blood cell production, meaning that the cognitive effects of an iron deficiency may precede the effects of iron deficiency anemia due to low hemoglobin. Another study demonstrates the use of cognitive test scores from children with iron deficiencies who were between the ages of five and nineteen in middle and low-SES families. It was found that the children with iron deficiencies had significantly lower test scores than those who maintained a good iron status. It was also distinguished that children that were born with chronic iron deficiencies and who were also in low SES families had notably low cognitive test scores (Lozoff et al., 2006). Both of these studies included older children, as it has been proven that children may not experience iron deficiency problems until they go to school. This is important to note as this demonstrates how the effects of iron deficiencies become more prevalent as a child grows. 

Iron deficiencies and iron deficiency anemia is more prevalent in children and mothers and is commonly found in low SES areas. It has been proven that the poorer and less educated a family is, the more likely their exposure to anemia is than people who are wealthy and whose parents are educated (Balarajan et al., 2011). Children who lived in low SES families also tended to have low iron levels due to the lack of attainable resources. In this case, low SES can be defined by factors including family structure, economic circumstances, parental education, and parental occupation (Lozoff et al., 2006). With this knowledge, there are some areas to be worked on in order to better help this issue of anemia and iron deficiencies. 

First, it would be constructive to have iron supplementations offered to the kids in need. For example, when giving nonanemic iron-deficient girls iron supplementation, their scores improved in verbal learning and memory compared to the control group who didn’t get supplementation (Bruner et al., 1996). In another instance, a food supplementation study in Guatemala found that early nutritional supplementation in adolescents eliminates the low test score in children that are associated with low SES (Lozoff et al., 2006). These are perfect examples of how giving children supplementation when they are still young can help them in the future as these nutrients promote better brain development. Secondly, it is known that anemia and iron deficiency in pregnant mothers are likely to pass down to their children, so it would be best to give mothers in low SES areas the necessary prenatal supplements. There could also be informative classes or lectures available around low SES areas that educate the mothers on what iron-rich foods they need to eat during pregnancy. Finally, screening children for iron deficiencies when they are young would be beneficial. Screening these children can be an indicator of malnutrition. So, if they are screened when they are young, early malnutrition can be determined, allowing these children to get the help they need more quickly. Taking these steps now is important so that, when these children grow up, they will be able to be well-educated so that the need for these areas of intervention will reduce. 

Malnutrition/SES

Malnutrition is an issue that is prevalent in children around the world. This can occur due to a multitude of reasons, including but not limited to inadequate amounts of nutrients from the food that a child needs. Specifically, there has been a correlation between malnutrition and low childhood cognitive development, parental level of education, and household income (Noble et al., 2015). Studies have shown that the impact of child malnutrition is present for a person’s entire life as malnutrition as an infant can interfere with crucial cognitive development during early childhood stages. Both stunting and iron deficiency anemia are seen as physical manifestations of malnutrition. This is important because there is a heavy association between poor IQ and malnourished children. This impact on cognitive development at a young age can result in cognitive delays into adulthood. Finally,  malnutrition is also associated with low socioeconomic status (SES), which will be explored further in this paper. 

Malnutrition as a child can have serious consequences later in adulthood. It has been observed that people who were malnourished during childhood can develop cognitive issues that last into adulthood (Waber et al., 2014)(Galler et al., 2012). The early years of a child’s life are essential as development occurs in all domains of the brain. Even though these parts of the brain develop at different times, the effects of disturbances with this development can have long-term impacts on the brain’s structural and functional abilities (Grantham-McGregor et al., 2007). Children born in Barbados were hospitalized for the first year of their life due to obtaining protein energy malnutrition. After the first year of their life, they were enrolled in a governmental intervention program to get the proper help they needed. When they reached adulthood, they were nine times more likely to have a decreased IQ than those without a history of malnourishment as a child (Waber et al., 2014). Figure 2 exemplifies how the IQ of the malnourished adults is lower compared to the healthy control group. The figure is notable because even though these children were only malnourished for the first year of their life before getting treatment, the figure shows that there are long-lasting developmental effects as a consequence of malnutrition by contrast to those who were never malnourished. This finding raises some concern that even after children who are malnourished as infants are adequately renourished, that doesn’t mean they will not have any cognitive deficits when they are adults. Moreover, a follow-up to this study demonstrated that children who were malnourished at age one were found to have lower SES status as adults compared to those who were not malnourished. Similarly, when comparing the household income between these two groups, the malnourished group had a significant income gap compared to the control group. The conductors of this study go on to express a theory that the neurological consequences of child malnutrition can limit both educational and job opportunities as an adult due to cognitive impairments (Galler et al., 2012). So, these studies demonstrate not only how infant malnutrition can lead to cognitive deficits as an adult but also how malnutrition can be linked to low socioeconomic status later in life. This expresses the necessity to take all means to avoid having a malnourished child because even if they get assistance to get the proper nutrients that they need, that doesn’t mean that they will not endure the disadvantages that come with their early malnutrition. 

Another study, similar to the last one, showed elevated attention problems in previously malnourished children. This study discovered that lower cognitive function in adulthood was related to poor scores on a laboratory-based measure of attention (Galler et al., 2012). Just like the previous studies, the children in this study from Barbados had malnutrition for the first year of their life. After this, the children were put into an intervention program where they were given the necessary resources. So, when observing how these people in adulthood still face the consequences of what happened in their infancy, it is crucial to understand that the developmental effects of malnutrition are persistent. This is likely because children within just one year of life struggling with malnutrition not only deal with the immediate consequences of malnutrition but, unfortunately, develop adult cognitive deficits regardless of interventions utilized. In contrast to the lasting effects of malnutrition, there have also been studies conducted about how parents who were malnourished in the early years of their life could have children with cognitive issues. However, this distinction could not be explained by the low socioeconomic status of the parent, nor could it be defined by the parent’s low IQ scores. Instead, the researchers of this study believe that this effect may be due to biological mechanisms. (Waber et al., 2018) This research point is significant as it establishes the need to lower malnutrition rates in low socioeconomic status regions. If previously malnourished adults can transmit cognitive impairments to their children, this trend of malnourishment and low SES may cease to end. This is important when considering how adults with low cognitive function are less likely to be educated or have a job due to their impairments (Galler et al., 2012).

Figure 2, (Waber et al., 2014)

Parental education has also played an essential role in their children's development. An association has been created between a child's malnutrition and parental education, which all connect to SES. A study focused on adolescent girls found many correlations between undernutrition and their parents' education levels. For example, it was observed that girls whose fathers were illiterate were most likely to be undernourished in comparison to fathers who achieved a college-level education. When following the occupations of these children’s fathers, there was an indication that the girls from fathers who worked as laborers were twice more likely to be underweight than those who had fathers who were merchants. Finally, there was an association between adolescent girls who had mothers with no education or basic primary education and were more likely to be malnourished than girls whose mothers had college-level education. This study also indicated that the girls who were wasted did not have much diversity in their diet, being that they mainly ate starchy or grain-heavy foods (Elhoumed et al., 2022). An observation can be made that children from fathers with lower-paying jobs are more likely to have malnourished children as they cannot afford to get their children the proper nutrients that their child needs due to their income. Similarly, it can be implied that uneducated mothers and fathers may have malnourished children due to their lack of knowledge of what they should be feeding their kids. This can be supported by the understanding that the wasted children did not receive all of the necessary food groups needed for their development. This information could be easily explained by either the parent’s lack of knowledge of what they need to feed their children or low income, which blocks the parents from affording the proper food their child needs for their development. In contrast, another study proved that parental education was associated with  a less likely chance of malnutrition. Parental occupation was linked to lower stunting, wasting, and thinness, so it was generally related to their children's nutritional status. Specifically, the mother’s level of education was significant if a mother was educated. If she was educated, there was a less likely chance for the children to be stunted or wasted (Madjdian et al., 2018). All this information is important as it proves that if parents are well-educated, their children will be less likely to suffer from malnutrition. When connecting this to the previous study, a conclusion that income is an indicator of malnutrition can be established as parents with better education are more likely to make more money than parents without an education. Similarly, the knowledge that educated mothers is essential as it brings up the argument that well-educated mothers may better understand what nutrients their child needs than mothers with little education. One more study connects income and parent education to the brain structure of adolescent children. It was seen that both family income and parental education were lined to the surface area of the brain. Specifically, the bilateral inferior frontal, cingulate, inulsa, inferior temporal regions, and the right superior frontal and recuneus cortex regions were observed. These regions were also associated with language and executive functioning (Noble et al., 2015). This study also found an association between lower parental education and their child’s left hippocampal volume. With this, the lower levels of education the parents had, the less hippocampal size was, indicating a directly proportional relationship (Noble et al., 2015). The connection between family income and parental education and lower cognitive ability in their children may be due to the indication that parents with a higher level of education will be more likely able to afford necessities for their children. These necessities are nutritious foods and more money to support their child’s education. Overall, these studies have indicated the importance of parental education when discussing their children's cognitive development. 

Children who are malnourished have a more likely chance of having low IQs. One study compared the IQs of three-year-olds and eleven-year-olds who were malnourished. These children faced psychosocial adversity, including the level of education their parents completed, the health of the parents, and the living conditions of the family children. In all, it was found that malnutrition associated with three-year-olds was linked to poor verbal and full-scale cognitive ability. Similarly, at age eleven, these children were associated with poor verbal IQ, spatial IQ, full-scale IQ, reading ability, and school performance (Liu et al., 2003). As confirmed by this study, psychosocial adversity and malnutrition are linked to children having low IQs. The connection between psychosocial adversity and malnourished children is crucial to understand as it explains how the children were unable to develop due to the lack of resources. Inevitably, the inability to allow the brain to develop fully will lead to these children having a more difficult time performing in school. This demonstrates the importance of helping families struggling to get the right resources their children need to grow to avoid poor academic performance due to malnourishment. 

When considering all of this information, a few steps can be taken to reduce the number of children who have malnutrition. Firstly, as it is indicated that lower parental education leads to a more likely chance that their children will be malnourished, there should be interventions made for parents. For example, it would be beneficial to set up workshops in areas with low SES that describe the correct nutrients a child needs to develop correctly. By doing this, the number of malnourished children will be reduced based on the more knowledge their parents have about what to feed them. Also, food groups, essential for the human brain to develop to its full potential, should be accessible and affordable everywhere. This will assist parents who don’t receive much income due to a lower-paying jobs. By making these foods more accessible and affordable, parents who struggle with putting food on the table will have a chance to give their children the right foods they need. 

Helping educate parents and providing healthy food options are ways to support families at risk of having children with malnutrition, which is very important for brain development. If the treatment is done in time, the malnourished children will have less severe, long-lasting effects. When observing the MRI information of children over six months old, the MRI observations found that cerebral atrophy and ventricle dilation were common encounters seen in the abnormal MRI findings. After six months of treatment, only one 

participant was still found to have abnormal findings in their cerebral atrophy (Bhargava & Singh, 2020). This study highlights the importance of treating children with malnutrition in the early stages of their life as this allows their brains to develop without malnutrition disturbing their development. 

Finally, it would be beneficial to add special assistance in schools to areas of the world with high rates of malnourished children. Even though there can be actions taken to eliminate the likelihood of malnutrition worldwide, there still needs to be a concern for those who are already malnourished. If the educational systems were simplified in these areas of low SES, where many children suffer from undernourishment, this would allow the children more time to process the information being taught. It is crucial to educate these children properly as they will be the next generation of workers in these underdeveloped countries, and they will dictate the number of malnourished children in the future. 

Conclusion

Undernutrition in adolescence is a global problem in many underdeveloped countries. Malnutrition is demonstrated in many forms, such as stunting, wasting, being underweight, or iron deficiency anemia. Malnourished children are more likely to encounter cognitive complications, which is shown through IQ tests and performance in school. However, undernourished children don’t only face mental consequences; they also experience physical changes, which are exhibited through stunting. Malnourished children who suffer some cognitive or developmental issues have a likely chance that they will suffer through the same problems as adults. Since the first few years of a child’s life is very important for childhood development, disruptions in this process can lead to long-lasting repercussions such as weakened cognitive function.

The impact of malnutrition on an individual's whole life highlights the need to establish interventions that can reduce the number of people diagnosed with malnutrition as a child. Providing nutritious meals in areas with high malnutrition rates can assist children who don’t have access to proper food. This lack of resources can originate from low family SES or uneducated parents who do not know what they should be feeding their children. In both of these cases, it would also be beneficial to hold educational lectures for parents describing what types of foods and food groups developing children need to grow to their fullest potential. Moreover, there should be places that screen for signs of malnutrition in areas that are heavily populated with malnourished children. For example, screening children for anemia in the early years of their life can identify if that child is showing signs of malnutrition. With the information from the screening, children will have the opportunity to be given the proper foods and can be monitored for improvement in the resolution of anemia. 

Interventions are only the start of what can be done to help malnourished children. This problem is prevalent around the world, which indicates that this problem needs to be solved quickly since these undernourished children are the people who will be responsible for the activities of the world in only a matter of years. Malnutrition is an issue that children worldwide, especially in underdeveloped countries, are going through, and this problem needs to be fixed.

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