Losing sleep can raise levels of hormones linked with appetite and eating behaviour.

In one study, people who slept only four hours a night for two nights had an 18 per cent reduction in leptin, a hormone that tells the brain there is no need for more food, and a 28 per cent rise in ghrelin, which triggers hunger.

Since the brain is fuelled by glucose, it is suspected the brain seeks simple carbohydrates when distressed by lack of sleep. It has been found that people tend to replace reduced sleep with added calories.

The researchers were particularly interested in the ratio of the two hormones - the balance between ghrelin and leptin.

After four hours of sleep, the ratio of ghrelin jumped 71 per cent compared with a night when the men slept nine hours.

The sleep-deprived men chose sweets, biscuits and cake over fruit, vegetables or dairy products.

A second study found that the less people slept, the more they weighed, using a measure called body mass index, which scales weight to height. A special GKA Body Mass Indicator (BMI) can be found on the GetKidsActive.com website here.

For more information on how you can help yourself and your family out by staying physically active and starting a new Active lifestyle contact us here at GKA on