School starting age and nutritional outcomes: Evidence from Brazil

Abstract

Recent studies reported that the age of primary school enrolment is a major driver of educational achievement and adult income, but its impacts on childhood health and nutrition remain largely unknown, particularly in developing countries where childhood stunting and overweight coexist. In Brazil, children are supposed to enrol in primary school the year they turn 6. Using a database of middle school students in Brazil based on a 2015 survey, I implemented an instrumental variables strategy using quasi-exogenous variations in the students' birthdates to isolate the impact of late primary school enrolment (i.e., older than 6 when enrolled) on height-forage and body mass-for-age indicators. Overall, late enrolment has protective effects against hazardous weight gain (− 0.14 z-score unit) but significantly increases the risk of moderate stunting (by 1.5% points). Heterogeneity in family backgrounds may explain these results. Indeed, delayed school enrolment is particularly detrimental for the nutritional status of students from underprivileged settings. In terms of public policy, rather than changing school starting age, this study highlights the importance of focusing on pathways to fight both stunting and overweight conditions in Brazilian children.

The effect of school-entry age on health is understudied in low- and middle-income countries: A scoping review and future directions for research

“…The three of the four articles from Türkiye were published between 2017 and 2019, when the country implemented legislative changes to school-entry age ( Gökçe et al, 2017 ; Öner et al, 2018 , 2019 ). The remaining studies used data from Brazil, Mexico, and Vietnam ( Caudillo, 2019 ; Caye et al, 2020 ; Levasseur, 2022 ; Nguyen & Lewis, 2019 ). All the LMIC studies included therefore were from upper-middle-income economy countries, except Vietnam which is lower-middle-income economy country ( Nguyen & Lewis, 2019 ).…”

“…There were no low-income economy country studies, and no published studies identified from the African continent. The exposure was generally defined as being young-for-grade ( Caudillo, 2019 ; Caye et al, 2020 ; Gökçe et al, 2017 ; Gümüş & Yürümez, 2021 ; Nguyen & Lewis, 2019 ; Öner et al, 2018 , 2019 ), with the exception of one quasi-experimental study from Brazil ( Levasseur, 2022 ), which defined the exposure as late enrollment compared to peers in the same grade (as opposed to early enrolment). In terms of outcomes, all 8 studies assessed health outcomes among children and youth aged between 0 and 22 years ( Caye et al, 2020 ).…”

“…In terms of anthropometric measurements, the evidence is more mixed. Instrumental variable estimates from Brazil suggest that being young-for-grade increased the probability of being overweight (defined as a BMI above 25 kg/m 2 ) but reduced the probability of being stunted (defined as height-for-age below 2 z-scores) in adolescence ( Levasseur, 2022 ). Specifically, being young-for-grade reduced the probability of being stunted by 1.5 percentage points.…”

“…Higher vulnerability to negative school exposures such as bullying among early starters ( Ballatore et al, 2020 ; Crothers et al, 2010 ) may also explain adverse mental health and potential weight gain ( Bauman et al, 2013 ; Black et al, 2011 ). In Brazil, the effect of delayed school enrollment was particularly detrimental for the nutritional status of students from underprivileged settings ( Levasseur, 2022 ). Late school entry may, for example, increase total childcare expenditures and reduce parental labor supply and earnings so that fewer household resources may be available to invest in food and nutritious ingredients ( Fig.…”

“…These existing studies on neurodevelopmental and mental health outcomes focus on drawing parallels with HICs and minimal research has been conducted on outcomes which are unique to LMICs. Only two studies, for example, assessed sexual and reproductive health outcomes ( Caudillo, 2019 ; Nguyen & Lewis, 2019 ) and only one study assessed nutritional outcomes, such as malnutrition ( Levasseur, 2022 ). The few studies that were available from MICs generally point to a negative association between being young-for-grade and health outcomes in childhood and adolescence, including in Mexico, Vietnam, and Türkiye ( Caudillo, 2019 ; Gökçe et al, 2017 ; Gümüş & Yürümez, 2021 ; Nguyen & Lewis, 2019 ; Öner et al, 2018 , 2019 ).…”