By: Stephanie von Hinke, PI ESSGN
Wartime rationing during and after World War II is often remembered as a period marked by scarcity, strict regulation and unpalatable diets. Yet a large body of research suggests that, in many respects, it had surprisingly positive effects on population health. By restricting access to food and prioritizing nutritional balance, rationing reduced dietary inequalities and ensured that people across the income distribution consumed similar quantities of key nutrients. Infant mortality fell, nutritional deficiencies declined, and overall dietary balance improved (Ministry of Health, 1946; Burnett, 2013).
Against this backdrop, one short period stands out. On 24 April 1949, rationing of confectionery (that is, chocolate and sweets) was suddenly and unexpectedly abolished. After seven years of confectionery rationing and restricted consumption, this caused a surge in average confectionery intake, with demand far outstripping supply. The confectionery industry struggled to respond, leading to some shops running out of stock and closing for business (Zweiniger-Bargielowska, 2000). The result was that, less than four months after the sudden derationing of confectionery, it was reinstated.
Given what we now know about sugar and health, this brief national surge in sugar consumption raises an obvious question: did it affect us in the long run? As a researcher studying the economics of health and dietary choice, I am particularly interested in questions like this. One key challenge in nutritional research is isolating the effects of specific foods or nutrients: when access to or availability of one food changes, people inevitably substitute to other foods. The rationing system however, which largely eliminated individual choice, removed this possibility. In effect, government policy created near-ideal conditions for studying the long-term consequences of early-life nutrition.
The 1949 derationing allowed us to examine a specific and important question: how does exposure to sugar in the womb, through the mother’s diet, affect offspring’s health and human capital later in life? To answer this, we combined micro-econometric methods with insights from genetics and data from the UK Biobank. Depending on the outcome studied, our analyses covered between 36,000 and 84,000 individuals born around the derationing period and observed in later adulthood.
What we found was perhaps unexpected: those exposed to more confectionery in the womb had slightly better outcomes in older age. On average, they had marginally lower body mass index, consumed less sugar in their 50s and 60s, and completed almost two additional months of education. Furthermore, individuals with a “genetic propensity” for a sweet tooth benefited more from derationing, with an even larger reduction in sugar consumption later in life (van den Berg et al., 2025).
One way to interpret these findings is through the lens of fetal programming, which posits that long-term outcomes improve when the prenatal environment is better aligned with the postnatal one. In this context, a high-sugar prenatal environment may better “program” the fetus to cope with a postnatal environment characterized by an abundance of sugar. This effect may be stronger for those who are genetically predisposed to high sugar consumption. Indeed, individuals who are genetically inclined to consume little sugar may not need “programming” to regulate their intake.
There are, however, alternative and complementary explanations. Because individuals inherit their genetic propensity for sugar consumption from their parents, our estimates may partly reflect additional confectionery exposure driven by parental preferences. This too is consistent with fetal programming though, in that the prenatal environment more closely matches the environment encountered later in life, reducing mismatch and improving long-run outcomes.
An alternative explanation is that access to confectionery boosted pregnant women’s happiness, which, in turn, could have led to an improvement in bonding with the newborn and hence more favorable offspring outcomes. In this case, the nutritional value of confectionery is not of prime relevance.
So what do these findings imply and what do they not imply? First, they do not suggest that high-sugar diets during pregnancy are advisable today. Post-war diets were generally more nutritionally balanced than modern diets, and the increase in sugar intake was temporary. What the study does show, however, is that conditions in the womb can have measurable effects many decades later. We show that even modest changes during pregnancy can leave a long shadow, underscoring the profound importance of the prenatal period for health, education, and public policy.
References:
van den Berg, G., S. von Hinke, A. Wang. 2025. Prenatal sugar exposure shapes late-life human capital and health. PNAS Nexus, 4(10), pgaf301. https://doi.org/10.1093/pnasnexus/pgaf301
Burnett, J. 2013. Plenty and want: A social history of food in England from 1815 to the present day. Routledge.
Ministry of Health. On the state of the public health during six years of war, 1946.
Zweiniger-Bargielowska, I. 2000. Austerity in Britain: Rationing, controls, and consumption, 1939-1955. OUP Oxford.
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