While studies have highlighted a link between breakfast consumption and cognitive performance, evidence for how breakfast influences academic outcomes is mixed. This study explored the association between student breakfast skipping and academic achievement.

This cross-sectional investigation employed population data. Self-reported breakfast consumption was used to categorise students as never, sometimes and always breakfast skippers. Scores on five standardised literacy and numeracy tests were used to classify students to have low or high achievement according to national minimum standards. Poisson regression analyses estimated the relative risk (RR) of low academic achievement among students across breakfast skipping categories, adjusting for student, family and community-level confounding.

Government schools in South Australia.

Participants included 28 651 students in grades 5, 7 and 9 (aged 8–16 years).

Overall, 32·3 % of students reported never skipping breakfast, 57·6 % reported sometimes skipping and 10·1 % reported they always skip breakfast. Students who sometimes and always skipped breakfast had an increased risk of low achievement on all five tests, after adjustment for confounding. Greatest risk for low achievement was on numeracy (RR = 1·78, 95 % CI 1·64, 1·94) and reading (RR = 1·63, 95 % CI 1·49, 1·77) among students who always skipped breakfast. Students who sometimes skipped breakfast were also at increased risk for low achievement, though not as higher risk as that among students who reported skipping breakfast every day.

Results suggest breakfast consumption plays an important role in academic success. Supports to promote regular student breakfast consumption may be one mechanism through which education stakeholders and policymakers can strengthen academic achievement.

Research on the consequences of breakfast skipping among students tends to focus on academic outcomes, rather than student well-being or engagement at school. This study investigated the association between breakfast skipping and cognitive and emotional aspects of school engagement.

Cross-sectional study using data from a population-level survey of children and adolescents’ well-being and engagement at school. Linear regression with adjustment for confounders was used to estimate the effect of breakfast skipping on school engagement.

Government schools (i.e. public schools) in South Australia.

The participants were students, Grades 4–12, who completed the Wellbeing and Engagement Collection in 2019. The analysis sample included 61 825 students.

Approximately 9·6 % of students reported always skipping breakfast, with 35·4 % sometimes skipping and 55·0 % never skipping. In the adjusted linear regression models, children and adolescents who always skipped breakfast reported lower levels of cognitive engagement (β = −0·26 (95 % CI −0·29, −0·25)), engagement with teachers (β = −0·17 (95 % CI −0·18, −0·15)) and school climate (β = −0·17 (95 % CI −0·19, −0·15)) compared with those who never skipped breakfast, after controlling for age, gender, health, sleep, sadness and worries, parental education, socio-economic status and geographical remoteness.

Consistent with our hypothesis, skipping breakfast was associated with lower cognitive and emotional engagement, which could be due to mechanisms such as short-term energy supply and long-term health impacts. Therefore, decreasing the prevalence of breakfast skipping could have a positive impact on school engagement.