Koca T, et al. – This study was planned to analyze breakfast habits, dairy product consumption, and physical activity and their relations with body mass index (BMI) in schoolchildren and adolescents. Evidence indicated that skipping breakfast was associated with overweight/obesity in schoolchildren and adolescents. Whereas, milk consumption offered a protective effect.

• This study included children aged 6–18 years.
• Height and weight were measured, and a BMI z–score was calculated for each child.
• By a self–report questionnaire, breakfast consumption frequency, intake of milk and other dairy products, physical activity habits, and mothers’ employment status were evaluated.
• To estimate the association between these habits and BMI z–scores, multiple linear regression analysis was applied.
• In total 7116 children were enrolled, 3445 (48.4%) female, with a mean age of 11.7 ± 2.7 years (5.8–18.9).
• Of these, 62.6% had breakfast every day.
• Collected data revealed that boys ate breakfast daily significantly more often than girls (64.5 and 60.7%, respectively;p < 0.001).
• The percentage of children eating breakfast daily decreased with age (79.1% at 6–11 vs. 52.1% at 12–18 years, p < 0.001).
• Sixty–four (0.9%) children consumed no dairy products.
• Findings displayed that milk intake was negatively and significantly associated with BMI z–score (β = – 0.103, p < 0.001).
• Cheese consumption and the mother being employed were positively and significantly associated with BMI z–score (β = 0.517, p < 0.001, and β = 0.172, p < 0.001, respectively).
• Children engaging in physical activity had higher BMI z–score values than others (0.22 ± 0.01 vs. 0.12 ± 0.02, p < 0.001).