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 wasting. This report is one output of a multi-phase scope of work, commissioned and funded by the UK Department for International Development (DFID) on “adopting a strategic, evidence-based approach to wasting prevention” and follows a briefing paper produced by ENN titled “The aetiology ofwasting”.2 The current report set out to answer the following questions: What do we know about wasting prevention? What is the emerging evidence? What are the evidence gaps and key questions which cannot currently be answered? What new evidence will be available in coming years?
Methodology
A detailed review of the evidence from both published and grey literature and from semi-structured interviews with stakeholders was conducted between December 2017 and February 2018. The prevention of wasting was considered across the main intervention contexts (humanitarian and development, those with low and high levels of wasting/low and high levels of stunting), along a ‘continuum’ of severity (moderate and severe wasting and prevention of relapse). The review looked at the evidence for so-called nutrition-specific and nutrition-sensitive actions.
In total 235 studies and articles from the literature search were included in the review, of which 55 were randomised control trials, 23 were protocols/ongoing studies and 17 were systematic reviews. Fifty-seven grey literature documents were reviewed and 46 experts/key stakeholders were interviewed.
Results
Historically there has been more of a focus on research into the prevention of stunting, while the prevention of wasting has been a more neglected research area. This is largely because the focus on wasting has been on treatment. Encouragingly, the review found that the volume of studies relating to wasting prevention has increased in recent years. However, the evidence base for the prevention of wasting is both mixed and largely inconclusive.
The interventions with the largest body of evidence include the use of supplementary food products, cash-based interventions, behaviour change to improve infant and young child feeding, and where interventions are combined. There is a lack of research on whether interventions targeted towards women and girls preconception and during pregnancy prevent wasting (see box 1 below).
The stakeholders consulted felt confident in stating that acute periods of food insecurity and/or episodes of disease outbreak contribute to wasting, and that well designed early interventions will have a preventive effect in such contexts. Despite an inconsistent evidence base, a holistic approach based on the UNICEF Conceptual Framework and context-specific causal analysis was advocated, through a range of interventions to tackle both the immediate and underlying drivers of undernutrition. It was felt that this should be complemented by an improved understanding of the epidemiology and aetiology of wasting to better identify and target children at highest risk.
Stakeholder opinion also suggested that much less is known about the prevention of wasting in non-humanitarian contexts or in areas with persistently high levels of wasting. Key gaps in the understanding of the aetiology of wasting were highlighted, including: kwashiorkor/ nutritional oedema; the relationship/overlap between stunting and wasting; differences relating to age and geography; the role of interventions preconception; the relationship between maternal nutrition and health status and child nutrition status; the extent to which wasting in infants under six months of age reflects non-nutritional factors (such as low birth weight); and mechanisms behind relapse after successful treatment for wasting. Other gaps included the role of infection and gut microbiota and the longer-term health and development impacts of childhood wasting.
Many stakeholders observed that there is an absence of a single organisation with an overall leadership role for wasting prevention. The divisions and silos which characterise wasting were also highlighted as a concern.
Box 1: Summary of state of evidence by intervention area
Breastfeeding
There is very little evidence of the impact of interventions to promote exclusive and continued breastfeeding on the prevention of wasting. Results are modest or difficult to attribute to an increase in breastfeeding alone.
Complementary feeding
Little evidence of the impact of complementary feeding interventions on preventing wasting was found. Some systematic reviews highlight the benefits, but studies including clear wasting outcomes are lacking.
Micronutrient supplementation
Only small impacts on wasting prevention were observed when using zinc supplements, despite some high-quality systematic reviews and clinical trials in this intervention area.
Nutrition counselling and nutrition education
A number of randomised clinical trials (RCTs) in this intervention area showed positive effects on the prevention of wasting, although many still fail to demonstrate a clear impact.
Deworming
Treating children known to have worm infection may have some nutritional benefits for the individual. However, despite some good quality studies, direct effects on preventing wasting have not been proved.
Maternal education, women’s empowerment and gender
Results predominantly from association studies and programme evaluations suggest that women’s empowerment interventions and education could have a positive impact on infant feeding and wasting.
Health
Few clear studies consider the relationship between health interventions and prevention of wasting. Only a few well designed studies found a limited impact on wasting reduction.
Water, sanitation and hygiene (WASH)
There is currently very little evidence as to the direct effect of WASH interventions in the prevention of wasting, with the exception of some studies on sanitation.
Agriculture and other livelihoods
Only limited impacts have been observed, suggesting that more needs to be done to link increased agricultural production with improving child nutritional status. Robust evidence relating to the impact of livelihoods interventions on wasting prevention is also lacking.
General food distribution (GFD)
Although a number of studies have shown an impact of GFD on wasting, it is difficult to attribute this to the intervention alone.
Cash transfers (CTs)
There is a growing body of well designed trials that are demonstrating a strong positive preventive effect of CTs on wasting.
Food supplementation
The highest number of studies was identified in this intervention area and evidence is growing quickly: well designed RCTs and systematic reviews have demonstrated the effect of food supplementation in preventing wasting, but questions around their cost-effectiveness and sustainability remain.
Combinations of interventions
The review found that a combination of interventions may be more effective at preventive wasting than separately implemented interventions, particularly when targeted to the same population.
The review identified numerous ongoing studies in the area of wasting prevention and some which are pending funding. Further evidence is anticipated in the coming years relating both to aetiology/epidemiology of wasting and effectiveness of various nutrition-specific and nutrition-sensitive interventions. Stakeholders stressed the importance of longer-term funding to facilitate research which encompasses the full 1,000 days window and a need for more longitudinal studies, including consideration of where existing data can be used (e.g. retrospective cohort studies). The need to improve the evidence base on drivers and effective approaches to wasting prevention through well designed programme monitoring and evaluation activities was also highlighted and several stakeholders supported the idea of a research prioritisation exercise.
ENN’s continued work in this area
ENN is continuing its focus on wasting prevention through the MQSUN+ mechanism by working with a team of experts to carry out a research prioritisation exercise on wasting prevention. This work will conclude in July 2019. Information on how you can participate in the exercise is available here.
ENN also continues to generate research publications and short briefs about the links between wasting and stunting (WaSt). Information about the WaSt project can be found here.
Endnotes
1ENN (2018) The current state of evidence and thinking on wasting prevention: MQSUN+ report. www.ennonline.net/resources/wastingpreventionreport2018
2ENN (2018) The aetiology of wasting: MQSUN+ report. www.ennonline.net/resources/aetiologyofwasting
More like this
Resource: The Current State of Evidence and Thinking on Wasting Prevention
A synthesis of published, grey literature and stakeholder opinion on what works to prevent wasting produced by the ENN, through the MQSUN+ project. This report compliments...
Blog post: Wasted opportunity? What we do know about preventing wasting
Today, over 50 million children are wasted, which comes with an elevated risk of death. Even more, wasting prevalence hasn't declined in recent years. The United Kingdom's...
Wasting Prevention Survey - Introduction
Background The global burden of wasting (50.5 million children 0-59 months of age)1 is a major global public health crisis and progress in reducing levels towards World Health...
en-net: Request for contributions of grey literature on wasting prevention
Dear all, ENN is currently conducting a review on behalf of DFID (via MQSUN+) on the prevention of wasting. Nutrition-specific and nutrition-sensitive activities to prevent...
Wasting Prevention
Donors: DFID funded MQSUN+ facility Collaborators: MQSUN+/PATH; Rebecca Brown and Jose Luis Álvarez Morán (ENN Consultants) ENN project lead and contact: Carmel...
Resource: Multi-sectoral Nutrition Programming – Exploring Impact
Executive Summary Multi-sector nutrition programmes (MSNPs) have gained increasing prominence over the last two decades in order to address the many direct and underlying...
FEX: The effects of food systems interventions on food security and nutrition outcomes in low- and middle-income countries
View this article as a pdf Report summary1 There is a significant global focus on improving food systems to address malnutrition and food insecurity in low- and middle-income...
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: Research priorities on the relationship between wasting and stunting
Summary of research* Location: Global. What we know: There is global momentum to bring down levels of undernutrition. Wasting and stunting frequently co-exist, but are often...
FEX: A review of research methods used to study specialised nutritious foods
View this article as a pdf By Kristine Caiafa, Maria Wrabel, Devika Suri, Ye Shen, Shelley Walton, Beatrice Lorge Rogers and Patrick Webb. All authors are affiliated with the...
FEX: Effects of nutrition interventions during pregnancy on low birth weight
Summary of research1 Location: Global What we know: Low birth weight (LBW) is a major underlying cause of infant mortality and childhood morbidity; LBW is greatly affected by...
Resource: Strengthening the Humanitarian Development Nexus for Nutrition in Protracted Crises
Introduction and Methods This synthesis report is based on a desk review on 'Strengthening the Humanitarian and Development Nexus [HDN] for Nutrition' and four country case...
FEX: Special Section: Research for Nutrition Conference - Editorial
Myriam Ait Aissa leads the Action Against Hunger Research and Analyses Department, which overall aim is to produce evidence for better action. Before joining Action Against...
FEX: Kwashiorkor – reflections on the ‘revisiting the evidence’ series
View this article as a pdf Lisez cet article en français ici By Merry Fitzpatrick, Gerard Bryan Gonzales, Alexandra Rutishauser-Perera and André Briend Merry...
FEX: Nutrition in emergencies: Do we know what works?
Summary of paper1 Location: Global What we know: Nutrition action in emergencies is well accepted and attracts significant resources. There is a lack of evidence on what are...
FEX: Livestock and nutrition: Summary of a discussion paper for the Livestock Emergency Guidelines and Standards
View this article as a pdf By Kate Sadler Dr Kate Sadler is a public nutritionist with over 20 years of experience in the design, management, evaluation and research of...
Resource: Antimicrobial and micronutrient interventions for the management of infants under 6 months of age identified with severe malnutrition: a literature review
Background Infants under 6 months (U6M) contribute a significant proportion of the burden and mortality of severe malnutrition globally. Evidence of underlying aetiology in...
en-net: Announcing a New Research Prioritisation Exercise for Improving Wasting Prevention
ENN are embarking on a research prioritisation exercise, for the UK Department for International Development (DFID) through the MQSUN+ project, on the critical subject of...
FEX: Research gaps and priorities in nutrition in emergencies
View this article as a pdf Eilise Brennan is a Nutritionist at Emergency Nutrition Network (ENN) Natalie Sessions is a Senior Nutritionist at ENN This views piece summarises...
Resource: ‘Wasting Reset’: wasting prevention, early detection and treatment to catalyse action and accountability- Solutions from the prevention of wasting working group
In recent years, whilst there has been an increase in interest and investment aimed at reducing wasting, including strong support from national governments, the pace of...
Reference this page
The current state of evidence and thinking on wasting prevention. Field Exchange 59, January 2019. p29. www.ennonline.net/fex/59/wastingprevention
(ENN_6226)