Being strict about your toddler's bedtime could help prevent him or her having problems with their weight later in life, according to a study.
Researchers in the US say that pre-school kids who manage to string out bedtime until after 9pm may be twice as likely to be obese later in life.
Lead researcher Sarah Anderson, associate professor of epidemiology at Ohio State University of Public Health, says in a statement: "For parents, this reinforces the importance of establishing a bedtime routine."
Obesity is a growing problem among children in the UK. Around a third of children are now overweight or obese. These conditions can set people up for disabling health problems later in life, including heart disease and type 2 diabetes.
Health campaigners are urgently waiting for the government's long-delayed strategy for tackling childhood diabetes.
Professor Anderson and her colleagues relied on data from 977 children who were part of an existing health study that began in the early 1990s. They categorised the children, with a typical age of 4-and-a-half, according to 3 different bedtime regimes:
8pm or earlier
Between 8pm and 9pm
The researchers then linked their bedtime habits to whether they were obese when they were teenagers, with an average age of 15.
They found that the results were quite striking and that:
Only 10% of the children with the earliest bedtimes were obese when they were teenagers
16% of the children who went to be after 8pm and before 9pm became obese
23% of those who went to bed after 9pm became obese by the time they were teens
Establishing a Routine
The research revealed that half of the children went to bed between 8pm and 9pm, while earlier and later bedtimes were divided equally between the other kids.
The researchers also examined how mother and child spent their time before bedtime and discovered that the children who went to bed later and whose mothers were least involved before bedtime were at highest risk of being obese later in life.
The study is published in The Journal of Pediatrics.
Although the researchers say that putting a young child to bed early does not guarantee they will fall asleep immediately, parents do have greater control about bedtime than when their child gets up in the morning. This can be particularly key when the child has older siblings who may be up making a noise getting ready for school and waking the rest of the household, they say.
The study comes with a caveat. "It's important to recognise that having an early bedtime may be more challenging for some families than for others," says Professor Anderson. "Families have many competing demands and there are trade-offs that get made. For example, if you work late, that can push bedtimes later in the evening."
Bedtime in Preschool-Aged Children and Risk for Adolescent Obesity, S Anderson et al, The Journal of Pediatrics
Press release, Ohio State University