Most of us know by now that obesity in adults is a growing problem, but less attention has been paid to the expanding waistlines of the younger generation.

According to a study conducted by Weight Watchers International Inc. and the American Health Foundation, 25% of American children are now officially overweight, and the youngest are especially at risk.

The American Dietetic Association (ADA) found that 14 percent of six- to 11-year-olds weighed more than they should, as did 12 percent of 12- to 17-year-olds. These extra pounds are more than just a passing phase; another ADA study suggests that half of obese adolescents will become fat adults.

"Obesity among children is increasing at an alarming rate, and the health consequences are very severe," confirms Karen Miller-Kovach, RD, chief scientist for Weight Watchers, who cites that the dramatic increase in Type II diabetes in teenagers is just one of the serious medical problems linked to the trend.

What's behind the growing number of chubby children? Simply, "lack of exercise accounts for more than 50 percent of the problem," says Miller-Kovach. And despite the popular belief that fast food is at the root of our collective portliness, she adds, just 30 percent of the problem is due to overeating or choosing the wrong types of foods.

Instead, experts point to cutbacks in school physical education programs, less time spent outdoors and more time playing video games or sitting in front of a computer, and even the rise in street crime, which makes parents uneasy about letting kids do things such as ride their bikes around the block.

So what can we do to help kids stay fit for the long haul, without making them anxious or weight-obsessed? There's no one-size-fits-all answer, says Miller-Kovach, but there are a few basic guidelines. Monitoring your child's every bite, for instance, is a tactic that's likely to backfire. " And you absolutely do not want to create a closet eater," she continues, which can happen when parents are overbearing about eating.

Rebecca Unger, M.D., an attending pediatrician at Children's Memorial Hospital, suggests keeping an eye on your child's height and weight without talking to him or her about being on a "diet." Instead, she suggests, "Talk about fitness and being healthy."

More ideas:

Put the squeeze on juice.

Many parents consider juice to be a healthful drink, and they serve it to kids in lieu of low-fat milk or water. But juice is high in sugar and calories. In fact, the American Academy of Pediatrics reports that many children wind up getting the majority of their calories from beverages, when they'd be better off getting them from fresh fruit and other healthful solid foods.

Toss the scale.

Instead of focusing on your child's weight, pay attention to other measures of fitness, such as whether he or she can walk a flight of stairs without feeling out of breath.

Check the medicine chest.

Sharon L. Hirsch, M.D., attending physician at Children's Memorial Hospital in Chicago and assistant professor in the department of child psychiatry at Northwestern University Medical School, says that, while rare, some prescription medications used to treat depression, autism and other conditions can cause weight gain. If your child is on medication and has gained weight despite a fairly active lifestyle, ask your pediatrician about this possible connection.

Get 'em moving.

Assign calorie-burning chores, such as walking the dog or mowing the lawn; or suggest active entertainment, such as bowling or a game of catch.

Don't use food as a reward.

Instead of candy and ice cream sundaes, Dr. Hirsch suggests that parents use stickers or new sports equipment to celebrate kids' accomplishments.

Practice what you preach.

Whether you look in the mirror and call yourself fat or you skip the gym to surf the Net, chances are your kids are watching you closely. Help them learn how to live a healthy lifestyle by practicing what you preach.

Help teach our children the importance of proper nutrition and fitness. Parents you may learn something too!
Check out Fitness and kids downloadable e-book "Fighting childhood obesity"