NNIW93 - Global Landscape of Nutrition Challenges in Children

The WASH Benefits Bangladesh , WASH Benefits Kenya and Sanitation, Hygiene, Infant Nutrition Efficacy (SHINE)  – Zimbabwe trials were cluster-randomized trials to test the independent and combined effects of improved water and sanitation/hygiene (WASH) and improved infant and young child feeding (IYCF) on child linear growth and hemoglobin concentration.

The trials were designed as “proof of concept" studies [4, 5]: the goal was to implement our best effort to minimize fecal ingestion in the WASH arms and optimize infant diet in the IYCF arms. The WASH Benefits trials had 7 arms (water chlorination, sanitation [pro-vision of an improved latrine], handwashing with soap [provision of two handwashing stations and soap], these 3 interventions together – WASH, IYCF (complementary feeding counseling and provision of 20g small quantity lipid-paste nutrient supplement [LNS]), WASH + IYCF, and a double-sized control arm which was passive in Bangladesh and active in Kenya. SHINE was a 2 × 2 factorial trial with 4 groups: WASH, IYCF, WASH + IYCF, and Standard of Care (SOC). Together the trials enrolled more than 19,000 pregnant women and measured their infants (15,500) at 18 months (SHINE) or 24 months (WASH Benefits) of age. 

The link between poor maternal nutrition and suboptimal infant and child outcomes is well established, but underlying mechanisms are not well understood [1]. Modifications to the developing offspring epigenome (Fig. 1) are a plausible mechanism for the transmission of intergenerational signals that could extend to effects of paternal nutrition mediated by epigenetic modifications in sperm.

One widely studied epigenetic mark involves the addition of methyl groups to DNA. DNA methylation (DNAm) marks are faithfully copied across cell divisions and can influence gene expression without altering the underlying DNA sequence. DNAm plays a key role in establishing and maintaining cellular identity. The DNAm must, therefore, be extensively remodeled in the very early embryo where embryonic cells are first reset to a pluripotent state, prior to the establishment of cell type-specific marks following separation into the embryonic germ layers at gastrulation.

Undernutrition affects almost 25% of all children under the age of 5 worldwide and underlies almost half of all child deaths. Child under nutrition is also associated with long-term growth deficits, in addition to reduced cognitive potential, reduced economic potential, and elevated chronic disease risk in later life. Dietary interventions alone are insufficient to comprehensively reduce the burden of child undernutrition and fail to address the persistent infectious burden of the disease. Although the role of infections is well recognized in the pathogenesis of undernutrition, an emerging body of evidence suggests that commensal microbial communities, known as the microbiome, also play an important role [1].

Protein is an important component of specialized foods to treat moderate acute malnutrition (MAM) and severe acute malnutrition (SAM). This is because wasting, the physiologic process that leads to acute malnutrition, is in large part reduction in the lean and functioning tissues of the body. It is generalized wasting of all organ systems that makes the wasted child more vulnerable. Protein is a category that represents all amino acids, the building blocks of almost all of the functional features of human cells. 

In addition to regions where vegetarian and vegan diets have a long cultural- and religion-based tradition, these diets have recently become more and more prevalent in Europe and other western countries. Furthermore, it is estimated that the prevalence of vegan-nourished adolescents and adults in Western Europe countries ranges from around 0.2 to 3% [1]. Reliable population-based numbers on vegan-fed infants and young children are as yet not available.

Vitamin B12 deficiency is common in vegetarian and economically deprived populations of the world. India provides a striking example. Unlike in the Western populations, this is not due to defects in the intrinsic factor-mediated gastrointestinal absorption but due to smaller intake of the vitamin in the diet. In nature, B12 is produced only by prokaryotes (microbes) and animals who eat microbes bring it in the food cycle. Smaller intake of animal origin foods is, therefore, a major cause of B12 deficiency. This may be driven by religious and cultural beliefs or poverty. Therefore, vegans and vegetarians and members of certain religions (Jain and Hindus) are at higher risk.

Cow’s milk has a stimulating effect on growth in young children. This has been shown for linear growth [1, 2], and it might also have an effect on accretion of lean body mass. The strongest evidence comes from intervention studies in low-income countries. The effect seems to be through a stimulation of IGF-I and insulin. There are several components of cow’s milk that are suggested to have a stimulating effect on growth [3]. The high-protein-quality score with a high content of especially the essential amino acids is likely to play a key role. Furthermore, the high content of lactose may act as prebiotics having an effect on the gut microbiota and a positive effect on mineral absorption [4].

The nutrient requirements of young infants are higher per unit body weight than at any other time of life. Those who are exclusively breastfed (EBF) consume on average about 750 mL/day between 1 and 6 months. There are substantial differences in daily milk intake among infants; on average the range is about 570–900 mL, but in reality it is even wider than this. It is assumed that milk intake is predominantly influenced by infant demand. But whether those who habitually consume less milk also have proportionately lower intakes of all nutrients has not been systematically studied – perhaps nutrients are more concentrated in milk of mothers who produce smaller volumes.

Almost 300 million children under 5 years are anaemic worldwide [1]. Iron deficiency has traditionally been considered to account for half of these cases. International policy makers recommend universal distribution of iron-based interventions – either iron supplements or iron-containing multiple micronutrient powders to alleviate the burden of anaemia in young children. More recent analyses indicate that the burden of anaemia attributable to iron deficiency is less than originally anticipated.

Reducing all forms of malnutrition represents a great challenge in many countries and recognizing population intake deficiencies is the first step to solve this problem. In this context, food composition tables or databases (FCT/FCDB) are an essential tool for dietary assessments as they provide the information required to convert food consumption data into energy and nutrient intakes [1–3].

Worldwide, fewer than one-third of children aged 6–24 months receive adequate dietary diversity and only about half receive a sufficient number of meals each day. Such suboptimal complementary feeding practices put millions of infants at risk for stunting and developmental delays. Food insecurity and/or limited access to high-quality foods continue during the preschool age years with implications for poor development and increased risk of facing the dual or even triple burden of malnutrition associated with protein-energy malnutrition, micronutrient deficiencies, as well as overweight or obesity.

Strategies to improve the adequacy of dietary intakes in young children have focused on improving both dietary quality and quantity of food consumed. While access to quality food that will meet the nutrient needs of young children remains a problem in many resource-poor settings, the importance of initiation and maintenance of sustained behavior change has been recognized as foundational to improving child feeding practices especially during the first 2 years of life. 

The first two years of life are a critical period to promote proper nutrition and dietary behaviors for optimal growth and development. Yet, almost 700 million children worldwide are suffering from malnutrition [1]. While undernutrition remains a significant problem, there continues to be an increase in the number of children who are becoming overweight as we undergo the nutrition transition. This transition is causing a shift in both dietary intake and physical activity that can impact childhood growth and development. Thus, there is a need to identify recommendations and interventions that will adequately prevent both the under- and overnourishment of children starting in infancy. 

Malnutrition during the first years of life has immediate adverse health consequences and impairs long-term health and capacities [1]. Children born small and those who become undernourished in early life are at higher risk of dying and are more susceptible to illness. Poor linear growth – stunting is associated with several physical and cognitive con- sequences and affects over 150 million children worldwide, one-third of whom live in India. Over 50 million children are wasted, half of whom live in South Asia, yet 5.4 million of the world’s 38.3 million overweight or obese children also live in South Asia. There is growing evidence that overweight in early life may be associated with the risk of noncommunicable diseases later in life.