Circadian dinner timing and BMI among adults in a Brazilian national survey

Aims To examine if the Time elapsed between Dinner and the Midpoint of sleep (TDM) is associated with BMI and obesity. Methods Participants (n = 1303) were part of a virtual exploratory, population-based survey. To evaluate differences in BMI associated with TDM we performed linear and quantile regression analyses. Logistic regression models were fitted to assess ORs (95%CI) of obesity associated with TDM. Restricted cubic splines were also used to study the shape of the association. Results We found a dose-response association between TDM and BMI, which decreased by 0.22 kg/m2 for each additional hour of TDM, with stronger and higher effects in the highest percentile of BMI. By increasing TDM, the odds of obesity decreased [OR (95%CI):0.87 (0.78,0.97); P = 0.01]. These associations were independent of age, gender, marital status, weekly duration of physical activity, and the largest meal of the day. Conclusions Because we found that having dinner farther from the midpoint of sleep was significantly associated with BMI, our data reflect the pertinence of assessing the circadian meal timing, along with the energy intake and the quality of meals, in nutritional recommendations and obesity prevention and treatment.