Temporal patterns of energy intake and physical activity and cross-sectional associations with body weight status in children and adolescents: results from the Portuguese National Food, Nutrition and Physical Activity Survey 2015-2016.

Temporal energy intake (EI) and physical activity (PA) patterns may be associated with obesity. We aimed to derive and characterise temporal EI and PA patterns, and assess their cross-sectional association with weight status, in 6-to-14-year-old Portuguese participants of the National Food, Nutrition and Physical Activity Survey 2015-2016. We extracted times and EI of all eating occasions from two 1-d food diaries/24-h recalls, while types and times of PA from 4-d PA diaries. We derived EI patterns (n 714) and PA patterns (n 595), using, respectively, a hierarchical and K-means cluster analysis, considering the average proportion of total daily EI (%TEI) and PA intensity (%TPA), within each 2-h interval across the 24-h day. Patterns were labelled based on the 2-h intervals of %TEI/TPA peaks. We assessed the association between patterns and overweight or obesity (BMI z-score ≥ +1 sd) using adjusted logistic regressions (OR (95 % CI)). Three EI patterns emerged: 1 - 'Early afternoon and early evening'; 2 - 'Early afternoon and late evening'; and 3 - 'Late morning, early and mid-afternoon and late evening'. EI Pattern 3 v. Pattern 1 was negatively associated with overweight or obesity (0·49 (0·26, 0·92)). PA Pattern 1 - 'Late morning, mid-afternoon and early evening' v. Pattern 2 - 'Late afternoon', was not associated with weight status (0·95 (0·65, 1·38)). A daily EI pattern with more and even %TEI peaks at earlier daytime periods, rather than fewer and higher, may be negatively associated with overweight or obesity amongst this population whereas the identified PA patterns might have no relationship.