"Childhood obesity very often leads to adult obesity. This puts them at greater risk of developing obesity-related cancers in adulthood," said study lead author Bernard Fuemmeler, Professor and Associate Director for Cancer Prevention and Control at the Virginia Commonwealth University.
‘Improper sleep in children is a risk factor for obesity and this puts them at greater risk of developing obesity-related cancers in adulthood.’
For the study, researchers enrolled 120 children, with an average age of eight, whose mothers had participated in the Newborn Epigenetic Study both pre-birth and during early childhood.
To track the sleep-wake cycle, the children wore accelerometers continuously for 24 hours a day for a period of at least five days.
They found that shorter sleep duration, measured in hours, was associated with a higher BMI z-score (body mass index adjusted for age and sex).
Each additional hour of sleep was associated with a .13 decrease in BMI z-score and with a 1.29 cm decrease in waist circumference.
More fragmented rest-activity rhythms and increased intradaily variability -- a measure of the frequency and extent of transitions between sleep and activity -- were also associated with greater waist circumferences.
The study results, to be presented at Obesity and Cancer: Mechanisms Underlying Etiology and Outcomes, indicate that while sleep duration is important, examining markers of sleep quality may also be useful in designing childhood obesity prevention strategies.
"Today, many children are not getting enough sleep. There are a number of distractions, such as screens in the bedroom, that contribute to interrupted, fragmented sleep. This, perpetuated over time, can be a risk factor for obesity," Fuemmeler said.
"Because of the strong links between obesity and many types of cancer, childhood obesity prevention is cancer prevention."