Breakfast skipping and timing of lunch and dinner: Relationship with BMI and obesity

To determine whether breakfast-skipping, late-lunch, and late-dinner eating are cross-sectionally associated with higher BMI and obesity. Also, to identify obesogenic behaviors and circadian-related variables, associated with late eating.

Participants(n = 776) were part of exploratory, population-based research, with data collection in a virtual environment. They were grouped into breakfast-eaters (first meal until 10:00) and skippers (first meal after 10:00), and the population median for the lunch and dinner timing was used to stratify participants into early (lunch/dinner-time before 12:34/20:55) and late (lunch/dinner-time after 12:34/20:55) eaters. Student's t-test and chi-square test were performed to assess differences in characteristics and lifestyle traits between groups. Logistic regression models were used to assess differences in obesity between groups. Linear regression analysis was conducted to determine the association of the clock time of meals with BMI. Analyses were adjusted for potential confounders variables.

BMI raised of 0.74 Kg/m2 for each additional hour of lunch-time [95 %CI= 0.31;1.18,P ≤ 0.001]. Breakfast-skippers [OR(95 % CI):1.84(1.02;3.31);P ≤ 0.05] and late-lunch eaters [OR(95 % CI):1.61(1.04;2.49),P ≤ 0.05] had higher odds of having obesity, compared with breakfast-eaters and early-lunch eaters, respectively. These associations were independent of age, gender, diet quality, physical activity duration, and region. No statistically significant differences were found in the comparison between early and late-dinner eaters.

Our results suggest that skipping breakfast and eating late-lunch are associated with BMI and higher odds of having obesity. Insights into the obesogenic behaviors/characteristics related to breakfast-skipping and late-eating may be helpful for future nutritional recommendations and obesity prevention and treatment.