Menu ENN Search

WASH interventions and their effects on the nutritional status of children

Summary of research1

Location: Global

What we know: Water, sanitation and hygiene (WASH) interventions are frequently implemented to improve health and reduce infectious diseases and may be linked to child development outcomes, including nutrition.

What this article adds: The strength of evidence linking WASH with child nutrition was investigated in a review of fourteen 14 randomised and non-randomised studies from ten low- and middle-income countries. The (poor quality) evidence suggests a small benefit of short-term WASH interventions in children under five years of age;, specifically solar disinfection of water, provision of soap, and improvement of water quality, in children under five years of age. The gap in rigorous evidence will be bolstered by ?ve large RCTs underway. Q; outstanding questions remain on long-term adherence, optimal timing and required duration of WASH interventions for optimal impact.

Globally, an estimated 26% of children (165 million) under the age of five years (165 million) suffer from chronic undernutrition manifested as stunting, and 8% (52 million) suffer from acute undernutrition manifested by extreme thinness or wasting.; Tthe largest numbers of undernourished children live in South Asia and Subsub-Saharan Africa. The two immediate causes of childhood undernutrition are inadequate dietary intake and infectious diseases such as diarrhoea. The integral role in health of safe water, sanitary disposal of human waste and personal hygiene has long been recognised. Water, sanitation and hygiene (WASH) interventions, such as provision of clean piped drinking water, enhanced facilities for excreta disposal and the promotion of hand-washing with soap, are frequently implemented to improve health and reduce infectious diseases and may be linked to child development outcomes. The objective of this review is to assess the strength of evidence linking WASH interventions with measures of child nutritional status and to identify research gaps.

The review includes evidence from randomised and non-randomised interventions designed to (i1) improve the microbiological quality of drinking water or protect the microbiological quality of water prior to consumption; (ii2) introduce new or improved water supply or improve distribution; (3iii) introduce or expand the coverage and use of facilities designed to improve sanitation; or (iv4) promote hand-washing with soap after defecation and disposal of child faeces, and prior to preparing and handling food, or a combination of these interventions, in children aged under 18 years.


Two review authors independently sought and extracted data on childhood anthropometry; , biochemical measures of micronutrient status; , and adherence to, attrition of and costs of the study interventions either from published reports or through contact with study investigators. The authors calculated mean difference (MD) with 95% confidence intervals (CI) and conducted study-level and individual-level meta-analyses to estimate pooled measures of effect for randomised controlled trials (RCTs) only.


Fourteen studies from ten low and middle-income countries involving a total of 22,241 children at baseline, and nutrition outcome data for 9,469 children, are included in this review. All studies included children under ?ve years of age years of age at the time of the intervention. The review included five cluster-randomised controlled trialsRCTs, (RCTs), one three-year follow-up of a cluster-RCT, and eight non-randomised studies with comparison groups. Studies included various WASH interventions either singly or in combination that aimed to improve the quality and quantity of water, and improve sanitation and hygiene.

Study duration ranged from six6 to 60 months. Measures of child anthropometry were collected in all 14 studies and nine studies reported at least one of the following Z-z score anthropometric indices: weight-for-height (WHZ), weight-for-age (WAZ) or height-for-age (HAZ). None of the included studies were of high methodological quality as the nature of the intervention was not masked from any participants.

Study-level and individual participant data (IPD) meta-analysis was limited to data from five cluster-RCTs with durations of 9-9 to 12 months. Meta-analysis including 4,627 children identified no evidence of an effect of WASH interventions on WAZ (MD 0.05; 95% CI -0.01 to 0.12). Meta-analysis including 4,622 children identified no evidence of an effect of WASH interventions on WHZ (MD 0.02; 95% CI -0.07 to 0.11). However, meta-analysis including 4,627 children showed that WASH interventions (specifically solar disinfection of water, provision of soap and improvement of water quality) had a slight but significant effect on HAZ   in children under 5 years of agefive (MD 0.08; 95% CI 0.00 to 0.16). In sub-group analysis of data from cluster-RCTs, there was some evidence to suggest a difference in effect by gender and age group, with girls more responsive than boys in weight and height growth to WASH interventions; height growth more responsive to WASH interventions in children under 24 months of age; and weight growth more responsive to WASH interventions in children aged 25-60 months of age. 

Adherence to study interventions was reported in only two studies (both cluster-RCTs) and ranged from low (< 35%) to high (> 90%). Study attrition was reported in seven studies and ranged from 4% to 16.5%. Intervention cost was reported in one study in which the total cost of the WASH interventions was USD 15 per /inhabitant. None of the studies reported differential impacts relevant to equity issues such as gender, socioeconomic status and religion.


The authors conclude that available evidence from meta-analysis of data from cluster-RCTs with an intervention period of 99-12 months is suggestive of a small benefit of WASH interventions (specifically solar disinfection of water, provision of soap, and improvement of water quality) on length growth in children under five years of age years of age. The quality of evidence is generally poor and the overall estimates presented are based only on meta-analyses of data from interventions of relatively short duration (99-12 months) from only a small selection of WASH interventions. These estimates are therefore not applicable to the effect that wider WASH interventions may have on child nutritional status.

The authors also conclude that this review has identified the paucity of rigorous evidence evaluating the effect of WASH interventions on child nutritional status. There are ?Five large RCTs are underway, which will contribute significantly to the existing evidence base linking WASH interventions to child nutritional status outcomes (see Box 1). Further research questions relate to the mechanism of action of the WASH interventions. There is no evidence on long-term adherence to WASH interventions, the optimal timing of interventions in childhood or the required duration of interventions to have the greatest impact on childhood nutrition outcomes.

Box 1: RCTs underway on WASH interventions and nutrition outcomes

Clasen T., Boisson S., Routray P., Cumming O., Jenkins M., Ensink J.H.J., et al. The effect of improved rural sanitation on diarrhoea and helminth infection: design of a cluster randomised trial in Orissa, India. Emerging Themes in Epidemiology 2012;9 (1):7.

Johns Hopkins Bloomberg School of Public Health. Sanitation, Hygiene, Infant Nutrition Ef?cacy Project (SHINE).

Innovations for Poverty Action. WASH Benefits Bangladesh: A Cluster Randomized Controlled Trial of the Benefits of Water, Sanitation, Hygiene Plus Nutrition Interventions on Child Growth.; Innovations for Poverty Action.

WASH Benefits Kenya: A Cluster Randomized Controlled Trial of the Benefits of Sanitation, Water Quality, Handwashing, and Nutrition Interventions on Child Health and Development.

Global Scaling Up Handwashing Project

Global Scaling Up Sanitation Project. 


1 Dangour, A.D.,; Watson, .L,; Cumming, O.,; Boisson, S.,; Che,, Y.,; Velleman,, Y.,; Cavill, S.,; Allen, E.,; Uauy, R. (2013) Interventions to improve water quality and supply, sanitation and hygiene practices, and their effects on the nutritional status of children. Cochrane Database Syst Rev, 8. CD009382. ISSN 1469-493X.

More like this

NEX: The effect of interventions to improve water quality and supply, provide sanitation and promote handwashing with soap on physical growth in children (Cochrane review)

Alan D Dangour et al. Cochrane Library 2013, Issue 7 Available online In low-income countries an estimated 165 million...

FEX: Independent and combined effects of improved WASH and improved complementary feeding on child stunting and anaemia in rural Zimbabwe

Summary of research1 Location: Zimbabwe What we know: Stunting and anaemia remain prevalent in children; plausible interventions have shown limited or inconsistent...

FEX: Upcoming research shared at ACF research conference

At the ACF research conference, November 6th, 2016, experiences were shared from a number of studies where final results will be made available in 2017. A snapshot of what to...

FEX: Association of early interventions with birth outcome and child linear growth in low-income and middle-income countries

View this article as a pdf Research snapshot1 The first 1,000 days of life represent a critical window for child development. Pregnancy and the exclusive breastfeeding (EBF)...

FEX: The current state of evidence and thinking on wasting prevention

Summary of research1 Background ENN produced a report, through the MQSUN+ programme, that synthesises existing evidence and stakeholder opinion on what works to prevent...

FEX: The WASH benefits and SHINE trials: interpretation of WASH intervention effects on linear growth and diarrhoea

View this article as a pdf Research snapshot1 Globally, stunting is the most prevalent form of child undernutrition and is only modestly responsive to dietary interventions....

FEX: Complementary food hygiene: An overlooked opportunity in the WASH, nutrition and health sectors

Summary of research1 Location: Global What we know: Poor food hygiene may account for a substantial proportion of diarrhoeal diseases and contribute to malnutrition among...

FEX: Nutrition-sensitive WASH programming to improve the nutritional status of women and children in Nepal

View this article as a pdf By Keshab Shrestha, Dhruba Dhital, Yubraj Shrestha, Dipak Raj Sharma and Dr Kenda Cunningham Keshab Shrestha is water, sanitation and hygiene...

FEX: The cost of a knowledge silo: A systematic re-review of water, sanitation and hygiene interventions

Summary of research1 By Michael Loevinsohn Michael Loevinsohn is a research fellow at the Institute of Development Studies, UK. An ecologist and epidemiologist, he has worked...

FEX: Evaluation of an integrated health-nutrition-WASH project to reduce malnutrition prevalence in children under two in Bangladesh

By Monsurul Hoq and John Brogan Monsurul Hoq was working as a Statistician Epidemiologist during the study. He has experience in monitoring and evaluation of community-based...

FEX: Impact evaluation of child caring practices project on stunting in Ethiopia

Summary of research1 Location: Ethiopia What we know already: Health, nutrition and water, sanitation and hygiene programmes impact on child nutrition. Evaluation of impact...

FEX: Letter on inadequate coverage of SAM in Lancet Undernutrition Series, by Susan Shepherd

SAM inadequately addressed in the Lancet Undernutrition Series Dear Editor, In 2003, The Lancet captured and focused attention on saving children’s lives with the publication...

FEX: Effect of a community-led sanitation intervention on child diarrhoea and child growth in rural Mali

Summary of research1 Location: Mali What we know: Community-led total sanitation (CLTS) is being scaled up, but there is limited evidence on child health impacts. What this...

FEX: Introduction to the special issue

The most recent Lancet series on maternal and child undernutrition (Bhutta et al, 2013) calculated that even with 90% coverage of specific nutrition interventions (addressing...

FEX: Impact evaluation of WASH in nutrition intervention on morbidity and acute malnutrition in Niger

View this article as a pdf Lisez cet article en français ici By SaïdouTamboura, Dr Moussa IssaLende and Lucia Pantella Tamboura Saïdou has worked in...

FEX: Role of nutrition in integrated early child development

Research Location: Global What we know already: Early child development (ECD) is a key predictor of future social capital and national productivity. Worldwide, 250 million...

FEX: Impacts of WASH on acute malnutrition: from available scientific evidence to informed action

View this article as a pdf Research snapshot1 Many of the 4.5 billion people who do not have access to improved sanitation or the 2.1 billion people who do not have access to...

Blog post: Research on multi-sectoral programming: reflections on a cash and WASH, nutrition integrated approach

Cliquez ici pour lire en français Some time ago I had the opportunity to attend a regional event for sharing multi-sectoral nutrition approaches, organized by ACF and...

FEX: Lipid-Based Nutrient Supplement Research Network Meeting

By Sarah Style Sarah Style is part of the ENN team working with UNHCR on the Anaemia Control, Prevention and Reduction Project In April 2011, the International Lipid-Based...

FEX: Water, livestock, and malnutrition findings from an impact assessment of Community Resilience to Acute Malnutrition programme in Chad

Summary of conference abstract and report By Anastasia Marshak, Helen Young and Anne Radday View this article as a pdf Presented at the ACF research conference, November...


Reference this page

Editors (). WASH interventions and their effects on the nutritional status of children. Field Exchange 51, January 2016. p50.



Download to a citation manager

The below files can be imported into your preferred reference management tool, most tools will allow you to manually import the RIS file. Endnote may required a specific filter file to be used.