In 1946, the Swedish government introduced state subsidies for municipalities that introduced nutritious school lunches free of charge for all pupils in primary school. The policy imposed strict nutritional standards on the meals served, which were to contain specified amounts of proteins, vitamins, calcium, and iron; adhere to a maximum fat content; and provide a third of the students’ daily caloric needs. These standards are similar to those introduced in more recent school meal programmes, such as the US School Meals Initiative for Healthy Children. Evaluating the Swedish school lunch programme constitutes a unique opportunity to improve our understanding of the long-term effects of such initiatives.
Despite the large potential gains of school meal programmes, and despite being around since the 1940s in Finland, Sweden, the UK, and the US, they have proven difficult to evaluate. The US school-lunch program, for instance, is federal, with little variation across areas, and commonly used quasi-experimental approaches are not easily applied (Hoynes and Schanzenbach 2015). It is therefore not clear how effective school meal programmes are relative to targeted programmes, such as the Food Stamp Program or the Head Start programme, in improving long-term outcomes (Hoynes et al. 2016, Niemesh 2015).
The lack of evidence is reflected in how different countries, especially in the EU, have adopted vastly different school meal policies. Sweden, Finland, and Estonia have long served nutritious school lunches to all pupils free of charge, while children in neighbouring countries, such as Norway and Denmark, bring their own packed lunches to school. France, Italy, and the UK serve school lunches according to nutritional standards, but the meals are means tested and come at a cost for most families. Germany has adopted a universal school lunch programme, but without any mandatory nutritional requirements.
We are aware of only one study that evaluates the long-term impact of school lunch provision. Using a change in the formula employed by the US federal government to allocate funding to states in the 1960s, Hinrichs (2010) studies the impact of the National School Lunch Program (NSLP) and finds large and positive effects on educational attainment. Hinrichs evaluates the effect of the NSLP before the 1995 nutritional guidelines were introduced; to date, no study has estimated the long-term impact of a policy that introduces school lunches with strictly controlled nutritional quality.1
In recent work (Lundborg et al. forthcoming), we provide evidence on the long-term benefits of universal school-meal policies. Specifically, we ask whether a policy that introduced nutritious school lunches free of charge for all pupils in Swedish primary schools between 1959 and 1969 improved children's economic, educational, and health outcomes throughout life.
In contrast to early-life programmes, school-based policies can reach a large share of children at a relatively low cost, and are therefore of particular interest. Policies that improve nutritional standards of school meals are especially interesting, since primary school is believed to be an important period for maintaining diets of high nutritional quality. Our study provides evidence that a universal programme offering school-aged children nutritious meals can be seen as an investment in their long-run human capital, with high internal rates of return.
The Swedish school lunch reform
We estimate the impact of the programme by using newly collected historical data on its gradual implementation across municipalities in Sweden between the years 1959 and 1969. During this period, 265 municipalities introduced the programme to a roughly equal number of municipalities each year. We have linked these historical data to administrative records that cover the population of primary school pupils, i.e. about 1.5 million pupils born between 1942 and1965. Using a difference-in-differences design, we estimate the impact of the school-lunch reform on a broad range of outcomes taken from income and education registers, the military enlistment register, the medical birth register, and hospitalization and mortality registers. Our main outcome – lifetime income – is calculated by summing up annual income between 1968 and 2011 using the Swedish income and taxation register.
We address several threats to our empirical design. We show that pre-treatment trends are parallel across early, mid, and late adopters of the reform, and our event-study estimates show that the effects of the programme arise for exposed but not for unexposed cohorts. Further, our results are robust to accounting for multiple-hypotheses testing, and to accounting for recent concerns that staggered difference-in-difference estimates may be biased in the presence of heterogeneity in the treatment effects over time or across groups.
Universal reform, universal effects
Using Sweden’s high-quality administrative data, we first show that both male and female pupils exposed to the programme became significantly taller, suggesting that improved nutrition is an important mechanism. Such positive effects of the reform were also manifested in large and positive effects on years of schooling and university attendance. Figure 1 shows that male and female pupils exposed for the full nine years became about 0.5 and 0.7 centimetres taller, respectively, and invested in 0.3 more years of schooling.
Figure 1 The effect of year of exposure to school lunches on height, schooling, and total income
a) Height return (cm)
b) School return (years)
c) Lifetime income return (%)
Our two most important findings concern lifetime income. We first show that the programme generated substantial long-term benefits: pupils exposed during their entire primary school period have 3% greater lifetime income compared to unexposed pupils (see Figure 1). Second, we find interesting heterogeneity in the effects: children from poor households benefit the most, although children from all households benefit to some extent. While pupils from poor households have 6% greater lifetime income compared to unexposed pupils, those from the other households still benefitted and have about 2% greater lifetime income (see Figure 2). Hence, applying the reform to all pupils led to universal effects.
Figure 2 The return to nine years of school lunches by household income quartiles
The height improvements, together with increased schooling, can also explain a large part of the effect of school lunches on lifetime income. We find no long-term effects on mortality, morbidity, sick leave, disability, or on health outcomes of children in the second generation. This is in line with the fact that the income effect is largest up to an individual’s mid-30s, and then gradually declines.
Nutrition and other possible mechanisms2
Long-run effects of school meal programmes can also arise through non-nutritional mechanisms, such as increased school attendance, improved household finances, and parental labour supply. To this end, we also collected and digitised data on school absence from municipality archives in Sweden, and show that the school lunch reform did not lead to any changes in school attendance rates, which were already high before the reform began. We also demonstrate that the reform led to small increases in parental labour supply and household income, but these effects are too small to explain our findings on lifetime income.
One reasonable interpretation of our results is that pupils became better equipped to absorb the material presented in school when eating a nutritious lunch every day. This interpretation is in line with the results in Belot and James (2011), where test scores among 11-year-olds increased within the first year of the introduction of nutritious meals, following the Jamie Oliver campaign in the UK. Similar results have been found in US high schools (Anderson et al. 2018).
Our results show substantial long-term economic beneﬁts of the Swedish school-lunch program. Moreover, the benefit-to-cost ratio of the programme is large – about twice the size of that of the Head Start programme (Kline and Walters 2016). The ratio for children from the poorest quartile of households is even larger, and in the same ballpark as those reported for highly selective welfare programmes such as the Perry Preschool Project and the Carolina Abecedarian Project, which both target children below age five from very disadvantaged backgrounds (Heckman et al. 2010).
We believe our results are relevant for Western countries today, even though the school-lunch programme was rolled out during the 1950s and 1960s. The programme was introduced in a wealthy country, where school children did not face food insecurity but where parents lacked knowledge about healthy food habits. The reform changed the nutritional content of the lunch meals and made pupils switch from less nutritious packed lunches or lunches at home. This is of relevance for many countries that plan to improve, or have improved, the nutritional content of food served in schools.
Anderson, M L, J Gallagher and E Ramirez Ritchie (2018), “School meal quality and academic performance”, Journal of Public Economics, 168: 81–93.
Belot, M and J James (2011), “Healthy school meals and educational outcomes”, Journal of Health Economics, 30(3): 489–504.
Butikofer, A, E Mølland, E and K G Salvanes (2018), “Childhood nutrition and labor market outcomes: Evidence from a school breakfast program”, Journal of Public Economics, 168: 62–80.
Currie, J and H Schwandt (2016), “Falling inequality in mortality in the US”, VoxEU.org, 2 July.
Heckman, J J, S H Moon, R Pinto, P A Savelyev and A Yavitz (2010), “The rate of return to the highscope perry preschool program”, Journal of Public Economics, 94(1–2): 114–128.
Hinrichs, P (2010), “The effects of the National School Lunch Program on education and Health”, Journal of Policy Analysis and Management, 29(3): 479–505.
Hoynes, H, D W Schanzenbach and D Almond (2016), “Long-Run Impacts of Childhood Access to the Safety Net”, American Economic Review, 106(4): 903–934.
Hoynes, H W and D W Schanzenbach (2015), “US Food and Nutrition Programs”, NBER Working Paper 21057.
Kline, P and C R Walters (2016), “Evaluating Public Programs with Close Substitutes: The Case of Head Start”, The Quarterly Journal of Economics, 131(4): 1795–1848.
Lundborg, P, D-O Rooth and J Alex-Petersen (forthcoming), “Long-Term Effects of Childhood Nutrition: Evidence from a School Lunch Reform”, Review of Economic Studies.
Niemesh, G (2015), “Ironing out deficiencies: Evidence from the United States on the economic effects of iron deficiency”, Journal of Human Resources, 50: 910–958.
Nunn, N and N Qian (2009), “Potatoes, the fruit of the earth”, VoxEU.org, 5 August.
Stewart-Brown, S (2012) “Are fruit and vegetables good for your mental health as well as your physical health?”, VoxEU.org, 11 November.
1 Butikofer et al. (2018) analyzed the long-term economic beneﬁts of a programme in Norway that replaced a hot meal at the end of the school day with a nutritious breakfast. We estimate the eﬀect of a universal programme that introduced nutritious school lunches to all pupils, whereas Butikofer et al. study a targeted policy that replaced a late meal with an earlier (and healthier) one, limited to children with particular needs for extra nutrition in urban municipalities.
2 See other VoxEU columns on nutrition and economic development (Nunn and Qian, 2009), nutrition and mental and physical health (Stewart-Brown 2012), and nutrition and mortality (Currie and Schwandt 2016).