The hidden factor in childhood obesity

Childhood, and adult, obesity is a topic of real concern and although much of the emphasis is on diet and exercise there could be a third, hidden, factor. A recent study done in Auckland, New Zealand, has revealed that young children who sleep less than nine hours a night have triple the risk of being overweight and have about 3% more body fat than children who get nine hours or more.

Although duration of sleep changes with the seasons, we sleep more in winter than summer for instance, but the New Zealand findings from a study of 519 seven-year-olds showed a definite link year-round between lack of sleep and obesity. On average, children in the study slept just over 10 hours a night, and those who went to bed after 9 p.m. were likely to sleep less. Again, on average, they had up to 40 minutes less sleep per night than children who went to bed earlier. These children’s weight gain is not because they are up raiding the refrigerator to pile on the pounds, but because the time the body needs for important maintenance processes has been reduced. The study also saw a link between lack of sleep and emotional instability such as mood swings or surliness, and indeed it can be seen in adults who don’t get enough sleep too.