# Associations between exposure to nutrition, WASH interventions and children’s academic performance in Ethiopia: a systematic review and meta-analysis

## TL;DR

This study finds that combining nutrition and WASH interventions improves academic performance in Ethiopian schoolchildren, especially for those with breakfast skipping or iodine deficiency.

## Contribution

The study is the first to evaluate the combined effects of nutrition and WASH interventions on academic performance in Ethiopian schoolchildren.

## Key findings

- Combined nutrition and WASH interventions significantly improved academic performance with a large effect size of 2.05.
- Subgroup analyses showed stronger effects for students who skipped breakfast or had chronic iodine deficiency.
- The study highlights the importance of integrating nutrition and WASH programs into school health initiatives.

## Abstract

Poor nutrition and inadequate WASH (water, sanitation, and hygiene) practices significantly impact children’s health, nutrition, and cognitive development, especially in low-income settings. These factors further aggravate the incidence of undernutrition, weaken the immune system, increase susceptibility to illnesses and reduce cognitive performance. Evidence on the effectiveness of existing WASH interventions is needed.

This review evaluated the effectiveness of nutritional and WASH interventions on the academic performance of children in Ethiopia.

A systematic search of Cochrane, DOAJ, Google Scholar, and PubMed (2010–2024) was conducted using MeSH terms and keywords related to WASH. Two independent reviewers screened studies and extracted data. Eligible studies included cross-sectional and cohort studies on Ethiopian schoolchildren with quantifiable academic outcomes. The JBI SUMARI was used to assess bias, and the GRADE approach was used to evaluate evidence quality. The meta-analysis used a random-effects model in Stata and reported pooled RRs with 95% CIs. Subgroup and sensitivity analyses examined moderators such as study design, intervention type, and sample size.

A total of 19 studies, 16 cross-sectional (n = 16) and three prospective (n = 3) cohort studies with a total of 9034 participants, were included. The random effects model revealed a significant improvement in academic performance among students receiving both nutrition and WASH, with a pooled large positive effect size of 2.05 (95% CI: 1.26, 2.28; I2=). In the subgroup meta-analysis, the effect of the intervention was more positive among those who skipped breakfast (3.47, 95% CI: 0.47, 6.47), chronic iodine deficiency (4.49, 95% CI: 4.08, 4.90), food insecurity (2.810, 95% CI: 1.281, 4.339), and underweight (0.61, 95% CI: 0.46, 0.75).

Despite moderate variability and some risk of bias, the evidence supports the integration of comprehensive nutrition and WASH programs into school health initiatives. Future research should focus on long-term effects and cost-effectiveness.

This systematic review and meta-analysis were registered in the International Prospective Register of Systematic Reviews (PROSPERO) under the ID CRD42024567265.

The online version contains supplementary material available at 10.1186/s12889-025-26107-4.

What is already known?

• Malnutrition (including undernutrition), breakfast skipping, iodine deficiency, poor hand washing practices, inadequate sanitation, and related diseases are key factors that impact cognitive development and academic performance.

• Previous studies in low-income countries, including Ethiopia, have confirmed these associations.

What are the findings of this study?

• Few or no high-quality studies have been conducted to evaluate the effects of nutrition and wash interventions on Ethiopian schoolchildren's academic performance.

• While many studies have examined nutrition or WASH separately, none have explored their combined effects—particularly among school-age children in Ethiopia.

What are the implications of the new findings?

• Our research revealed that WASH and nutrition have a major influence on Ethiopian students' academic achievement.

• Skipping breakfast and having a chronic iodine shortage have detrimental effects on learning, impairing focus and cognitive function.

The online version contains supplementary material available at 10.1186/s12889-025-26107-4.