Girls who devote much time to the Internet, get too little sleep or regularly drink alcohol are more likely to turn overweight than their peers. To examine whether or not spending prolonged hours at the Internet, getting insufficient sleep, and regular alcoholic consumption promote weight gain, researchers followed 5,036 girls aged between 14 and 21 years. They were surveyed regarding the number of recreational hours per week they spent on the Internet, which ranged from 1 to 5 hours, to more than 16 hours, as well as how long they slept each night (anywhere from 5 hours or less, to 9 hours or more) and how much alcohol they usually drank (ranging from none to two or more drinks per week). After a follow-up of a year, it was found that the more time girls spent on the Internet, the more their body mass index (BMI) increased, particularly among girls younger than 18 years. Similar patterns were seen when the researchers looked at alcohol consumption and sleep. Those who reported sleeping for 5 hours or less tended to gain more weight than those who got a standard 8-hour sleep. And girls and women who had 2 or more alcoholic drinks per week put on more pounds than those who drank the least. Spending hours on the Internet contributes to weight gain by taking time away from physical activity. Lack of sleep may make people too tired to be active during the day and sleep deprivation also affects hormones and metabolism in a way that might promote weight gain. Meanwhile, alcohol contains a significant amount of calories, and research suggests that people usually don't adjust for liquid calories by eating or drinking less throughout the rest of the day. The findings suggest that replacing recreational Internet time with sleep and by avoiding alcohol young women can stay fit and loose weight.
The Journal of Pediatrics
July 2008