Adults aren't the only ones who may suffer from obesity if sleep-deprived. Harvard has released a study that indicates babies and toddlers who sleep less than 12 hours each day are more likely to be overweight by the time they walk up the front steps for their first day at preschool. Too much Dora the Explorer could worsen the problem; the children who watched the most TV and slept the least were found to be at the greatest risk of obesity.

The research began at six months of age, when mothers reported how much of the day their baby spent sleeping, both at nap time and during the night. The mothers then reported the same information at one and two years of age. They also reported the amount of television the toddlers were watching starting at age 2. After using the information to find an average pattern for the first two years of a child's life, the researchers found that seven per cent of children who slept 12 hours or longer per day were obese by the time they reached three years old. Of the children who received less than 12 hours of shut-eye per day, 12 per cent were obese by age three. Of the children studied, 17 per cent of those who slept less than 12 hours and watched at least two hours of television each day, were overweight by age three.

"The two (behaviors) are acting independently. In combination, they are particularly risky," said the study's lead author, Dr. Elsie Taveras of Harvard Medical School.

The detailed results of the study can be found in the April edition of Archives of Pediatrics & Adolescent Medicine.

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