Environmental Risk Factors Associated with Child Stunting: A Systematic Review of the Literature

Abstract

Background:Stunting, a form of malnutrition characterized by impaired linear growth in the first two years of life, affects one quarter of children globally. While nutritional status remains the key cause of stunting, there is evidence that environmental risk factors are associated with stunting.Objective:The objective of this review is to explore the current literature and compile the environmental risk factors that have been associated with stunting. Further, we seek to discover which risk factors act independently of nutritional intake.Methods:A systematic search of the literature was performed using PubMed, EMBASE, Scopus, TOXNET, and CINAHL. A search of the grey literature was conducted. Papers were included in this review if they examined an association between childhood stunting and exposure to environmental risk factors.Findings:We included 71 reports in the final analysis. The included studies showed that foodborne mycotoxins, a lack of adequate sanitation, dirt floors in the home, poor quality cooking fuels, and inadequate local waste disposal are associated with an increased risk of childhood stunting. Access to safe water sources was studied in a large number of studies, but the results remain inconclusive due to inconsistent study findings. Limited studies were available for arsenic, mercury, and environmental tobacco, and thus their role in stunting remains inconclusive. The identified research did not control for nutritional intake. A causal model identified solid fuel use and foodborne mycotoxins as being environmental risk factors with the potential to have direct effects on childhood growth.Conclusions:A diverse range of environmental risk factors are, to varying degrees, associated with stunting, demonstrating the importance of considering how the environment interacts with nutrition. Health promotion activities may be more effective if they consider environmental factors alongside nutritional interventions.

Water, food, and the dual burden of disease in Galápagos, Ecuador

“…Contrary to a large literature linking water quality to UND/ID (Günther & Fink, ; Vilcins, Sly, & Jagals, ) and more limited literature linking water quality to OWT/NCD (Liu, Balasubramaniam, & Hunt, ; Ritter, ; Ritter, ), we found no individual effects of either water access or quality in our main analysis. Access to drinking water has been linked to reduced morbidity from infectious illnesses (Bivins et al, ; Gamper‐Rabindran, Khan, & Timmins, ) and, less consistently, with a reduced risk of child stunting (Vilcins, Sly, & Jagals, ). Our previous work in the Galápagos similarly found no significant associations between water quality or access and stunting or diarrheal morbidity among children, suggesting that these measures are either too crude to capture pathogen exposures or that other factors are buffering children from stunting in this context (Nicholas et al, under review).…”

“…Similarly, the components of the dual burden also tend to be inversely associated with income in LAC. Obesity, hypertension, and diabetes have all been found to be higher with lower income (Fleischer, Roux, Alazraqui, & Spinelli, ) and lower income is a well‐established risk factor for stunting and undernutrition (Vilcins, Sly, & Jagals, ). Interestingly, place of birth, our measure of migration status, was also associated with the dual burden.…”

“…First, our measures of water access and quality are based on a limited number of survey questions and then dichotomized due to the non‐normality of their distributions. Such measures have been criticized for masking potential variability within “improved” and “non‐improved” sources of water and for not addressing potential sources of contamination introduced during water usage (Vilcins, Sly, & Jagals, ). We chose to dichotomize our water quality variable into purchased water vs all other treatment sources (ie, boiling, using filters, adding chlorine, etc) based on literature showing inconsistent adherence to water treatment recommendations (Arnold & Colford Jr, ; Brown & Sobsey, ).…”

“…These changes in diet have outpaced water and sanitation improvements in many LAC (Willaarts, Garrido, Soriano, Molano, & Fedorova, ), which suffer from limited water access and poor water quality. Contaminated drinking water is associated with undernutrition and increased morbidity from infectious conditions, including diarrhea and urinary tract infections (Günther & Fink, ; Hunter, MacDonald, & Carter, ; Vilcins, Sly, & Jagals, ). Contaminated water also plays a role in the development of small intestine bacterial overgrowth and subclinical environmental enteropathy, both of which can contribute to underweight and stunting in children (Brown, Cairncross, & Ensink, ; Donowitz & Petri Jr, ) and micronutrient deficiencies in children and adults (Guerrant, DeBoer, Moore, Scharf, & Lima, ).…”

Four papers on child growth modelling

“…While the project has much broader potential, it began with and still has a primary focus on child growth and development. Such a focus is well warranted, since even with all today's modern advances in science and health, approximately a quarter of the world's children suffer from impaired growth due to nutritional deficiencies and other environmental factors . The project has created and continues adding to an impressive repository of data from studies conducted all over the world.…”