Lack of shut-eye contributes to the risk of obesity, according to many recent studies. In exploring childhood obesity, Johns Hopkins University researchers recently completed a meta-analysis of 11 studies that looked at children's sleep duration and their body mass. Not getting enough sack time, the scientists confirmed, disrupts hormone levels, which may lead to excessive weight gain.

Minimum sleep recommended for children:

Younger than 5 years: 11 hours

5–10 Years: 10 hours

Older than 10 years: 9 hours

Increase in odds of being overweight if the child sleeps less than the minimum recommended hours by:

1 Hour: 43 percent

1–2 Hours: 60 percent

More than 2 hours: 92 percent

SOURCE: Obesity, February 2008