Kids love staying up late - whether it's an extra bedtime story, a special TV programme, or even just playing with a tablet. But that little indulgence could lead have more harmful effects than just bleary eyes the next morning, with a new study finding that late nights could equal flawed dietary habits.
The study, published in the International Journal of Obesity, found that toddlers who accrue less than ten hours of sleep per day tend to carry more weight than those who manage to sleep thirteen or more hours per day. The former group tended to consume one-tenth more calories than the latter group, accumulating to around 105 additional kcals per day.
Researchers from the University College London compared data from 1,300 sets of twins by first observing their sleeping patterns at the age of 16 months and then monitoring their food consumption in the five months following. The study was borne of an increased interest in childhood obesity, with researchers basing their thesis on a lack of sleep lifting the risk of obesity. The link between the two is now more apparent, with a lack of sleep leading to the increased consumption of calories, hence resulting in higher body mass. The lack of sleep was also thought to increase irritability and low mood in young children, resulting in parents placating them with more food.
"We know that shorter sleep in early life increases the risk of obesity, so we wanted to understand whether shorter sleeping children consume more calories," said researcher Dr. Abi Fisher, of the Health Behavior Research Centre at UCL.
"Previous studies in adults and older children have shown that sleep loss causes people to eat more, but in early life parents make most of the decisions about when and how much their children eat, so young children cannot be assumed to show the same patterns," she added.
Sleep loss has long been acknowledged as detrimental to adult's weight management, with interrupted circadian rhythms thought to be connected to a fluctuation in hormonal levels. Tam Fry, from England's National Obesity Forum pointed to the relationship between parenting techniques and toddler's weight. "When adults don't get enough sleep they snack more and feed themselves with comfort food. It's slightly different with babies but they become irritable so parents give them more food to soothe them believing it's an act of love," said Fry.