Shorter sleep among adolescents is associated with lower fruit and vegetable consumption the following day.
The international journal of behavioral nutrition and physical activity 2023 ; 20: 12.
Winpenny EM, Rowthorn H, Hollidge S, Westgate K, Goodyer IM, Brage S, van Sluijs EMF
DOI : 10.1186/s12966-023-01420-6
PubMed ID : 36750845
PMCID : PMC9906927
URL : https://ijbnpa.biomedcentral.com/articles/10.1186/s12966-023-01420-6
Insufficient sleep has been associated with weight gain and metabolic dysregulation, with one suggested mechanism being through reduction in diet quality. Experimental evidence supports a causal effect of sleep timings on diet but this may not be applicable to a free-living adolescent population. In this analysis we use daily measures of sleep timings and diet quality, to examine the effect of sleep duration and timing on diet quality the following day among free-living adolescents.
The ROOTS study is a prospective cohort recruited from secondary schools in Cambridgeshire and Suffolk (UK). Participants (n = 815) at mean age 15.0y (SD 0.3y) completed a diet diary and wore a combined heart rate and accelerometer device over 4 consecutive days. Sleep duration and timing (midpoint) were derived from acceleration and heart rate traces, while daily energy density and fruit and vegetable intake were calculated from dietary data. Analyses were performed at day-level (1815 person-days). Multilevel random effects models were used to test associations between sleep each night and subsequent day diet, with daily sleep and diet measures nested within individuals and schools, and adjusted for day-level and individual-level confounding variables.
Adolescents slept a mean of 7.88 hrs (SD 1.10) per night, reporting a mean energy density of 2.12 kcal/g (SD 0.48) and median energy-adjusted daily fruit and vegetable intake of 137.3 g (IQR 130.4). One hour shorter sleep duration was associated with lower intake of fruit and vegetables (-6.42 g, 95%CI -1.84, -10.99) the following day. An association with higher dietary energy density (0.016 kcal/g, 95%CI 0.034, -0.002) the following day was observed but did not reach statistical significance. Sleep timing was not associated with either fruit and vegetable intake (-2.52 g/d, 95%CI -7.66, 2.62) or dietary energy density (-0.001 kcal/g, 95%CI -0.022, 0.020).
Our observational findings from a free-living adolescent population support the experimental evidence for a causal role of sleep on diet, with shorter sleep duration at night leading to a small decrease in diet quality the following day. These findings support experimental evidence to suggest inclusion of sleep duration as one component of interventions designed to improve diet quality and weight status in adolescents.
We know that poor sleep or not enough sleep is linked to weight gain and poor heart health, and studies have suggested that this may be related to poor diets and high caloric intake. However, although trials of severe sleep restriction show increases in appetite and energy intake, we don’t have good evidence on this topic from adolescents who are choosing their own sleep patterns. This study used daily data on sleep duration and diet from adolescents (age 15) from the ROOTS cohort study, a sample recruited from secondary schools in Cambridge in 2005-2007. We studies how sleep each night influenced the amount of fruit and vegetables consumed, and the overall energy density of the food consumed on the following day.
Our analysis found that shorter sleep at night was followed by a lower intake of fruit and vegetables the next day, and a higher overall energy density of food. However, the timing of sleep (whether people went to bed and woke up later or earlier) was not relevant for fruit and vegetable intake or energy density of food.