The relationship between diet and sleep in 2-y-old children: Results from Growing Up in New Zealand

Objectives: This study aimed to examine the relationship between dietary practices and sleep in young children.Methods: In this study, 2-y-old children (n = 6327) and their mothers were enrolled at birth and during preg-nancy, respectively. The study obtained maternal demographic, health, and lifestyle data during late preg-nancy. Parents reported the 2-y-old child's dietary practices on a food frequency questionnaire, as well as sleep duration and night-waking frequency. Measures of dietary intake quantified servings per day for each food group (grouped as low/moderate/high intake). Sleep measures were as inadequate sleep when <11 h sleep in a 24-h period and increased night waking when waking >2 times per night. Multivariable logistic regression analyses examined associations between toddler diet and sleep, which were described using adjusted odds ratios (ORs) and 95% confidence intervals. Results: In this study, 2-y-old children (n = 6288) slept for a mean of 12.3 hours (standard deviation: </n>1.5 hours) over a 24-h period, with 734 children (12%) getting <11 h of sleep in 24 h. Increased night waking occurred in 1063 children (17%). Compared with low intake, high soft drink/snack/fast food intake was asso-ciated with inadequate sleep (OR: 1.37) and increased night waking (OR: 1.34). High milk/cheese/yoghurt intake (OR: 1.55) was associated with increased odds of night waking, but moderate (OR: 0.81) or high (OR: 0.78) vegetable intake was associated with decreased odds of night waking. Exposure to screens (OR: 1.28) and heavy maternal cigarette smoking (OR: 2.20) were also associated with inadequate sleep and increased night waking, respectively.Conclusions: At age 2 y, higher consumption of soft drinks/snacks/fast foods is associated with shorter, more disrupted sleep. Conversely, higher vegetable consumption is associated with less disrupted sleep. Dietary modifications may improve toddlers' sleep.(c) 2021 Elsevier Inc. All rights reserved.