Recent cross-sectional studies found higher consumption of energy-dense foods among children with short sleep duration; however, longitudinal studies examining changes in sleep and diet over time are needed.
This study aimed to investigate prospective associations between changes in objectively measured sleep duration and alterations in proposed dietary risk factors for obesity in 8-11-year-old Danish children.
Four hundred forty-one children recorded dietary intake during seven consecutive days, along with accelerometer measurements estimating sleep duration at baseline and after ~200 days.
Baseline sleep duration did not predict changes in dietary intake or vice versa (all P?=?0.69). However, 1-h lower sleep duration was associated with higher intake of added sugar (1.59 E%; P?=?0.001) and sugar-sweetened beverages (0.90 E%; P?=?0.002) after 200 days with no change in energy density of the diet (P?=?0.78).
Our results suggest that a negative change in sleep duration is associated with higher intakes of sugar containing foods/beverages.
To examine independent and combined cross-sectional associations between movement behaviors (physical activity (PA), sedentary time, sleep duration, screen time and sleep disturbance) and fat mass index (FMI), as well as to examine longitudinal associations between movement behaviors and FMI.
Cross-sectional and longitudinal analyses were done using data from the OPUS school meal study on 785 children (52% boys, 13.4% overweight, ages 8-11 years). Total PA, moderate-to-vigorous PA (MVPA), sedentary time and sleep duration (7 days and 8 nights) were assessed by an accelerometer and FMI was determined by dual-energy X-ray absorptiometry (DXA) on three occasions over 200 days. Demographic characteristics, screen time and sleep disturbance (Children's Sleep Habits Questionnaire) were also obtained.
Total PA, MVPA and sleep duration were negatively associated with FMI, while sedentary time and sleep disturbances were positively associated with FMI (P?0.01). However, only total PA, MVPA and sleep duration were independently associated with FMI after adjustment for multiple covariates (P0.05), but higher FMI at baseline predicted a decrease in total PA and MVPA, and an increase in sedentary time (P?0.001), even in normal-weight children (P?0.03).
Total PA, MVPA and sleep duration were independently associated with FMI, and combined associations of movement behaviors showed a synergistic effect with FMI. In the longitudinal study design, a high FMI at baseline was associated with lower PA and higher sedentary time after 200 days but not vice versa, even in normal-weight children. Our results suggest that adiposity is a better predictor of PA and sedentary behavior changes than the other way around.
1] Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark  Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.
Lack of sleep and increased consumption of energy-dense foods and sugar-sweetened beverages (SSBs) have all been suggested as factors contributing to the increased prevalence of overweight and obesity.
To evaluate whether objectively measured sleep duration (average and day-to-day variability) as well as parent-reported sleep problems are independently associated with proposed dietary risk factors for overweight and obesity in 8-11-year-old children.
In this cross-sectional study, data on sleep duration and day-to-day variability in sleep duration were measured in 676 Danish, apparently healthy children by an objective measure (actigraphy) for 8 nights, and the Children's Sleep Habits Questionnaire (CSHQ) was filled out by the parents. Diet was recorded using a web-based food record for 7 consecutive days. Fasting blood samples were obtained for measurements of plasma leptin and ghrelin levels.
Sleep duration (h per night) was negatively associated with energy density (ED) of the diet (ß = -0.32 kJ g(-1)), added sugar (ß = -1.50 E%) and SSBs (ß = -1.07 E%) (all P = 0.003). Furthermore, variability in sleep duration (10-min per night) was positively associated with SSBs (ß = 0.20 E%, P = 0.03), independent of sleep duration, and CSHQ score was positively associated with ED (ß = 0.16 kJ g(-1), P = 0.04). All of these associations were independent of potential confounders (age, sex, pubertal status, height, weight, screen time, moderate-to-vigorous physical activity and parental education and ethnicity).
Our study suggests that short sleep duration, high sleep duration variability and experiencing sleep problems are all associated with a poor, obesity-promoting diet in children.