More than 50 percent of Americans are overweight, and almost 27 percent are obese, says Dr. Suzette Jelinek, Extension network and marketing specialist. Tens of millions of Americans diet each day, yet 60 percent are inactive, meaning they get little or no regular exercise.

Children are as sedentary and overweight as adults, and that is dangerous, says Jelinek.

"How can any child have really good self-perception and self-esteem if he is heavy and isn’t able to participate in sports and physical activity and just be a kid? Studies show the more TV you watch, the heavier you’re going to be," she says.

Children form their attitudes about nutrition and exercise by watching their parents. So parents must model good eating and exercise habits for their children, she says. If kids learn good habits while they’re young, they are more likely to continue those good habits as adults.

"Unfortunately for small children, parents decide what they eat," says Dr. Barbara Struempler, Extension nutritionist. "And it’s very important that parents not make meals that are fried or high in fat. Parents must enforce the importance of fruits and vegetables over poor snack choices, like chocolate and candy. I’m a firm believer that the more calories you can get from food rather than empty calories from soft drinks, the better off you are. Choose milk for your child instead of a soft drink, or water instead of a soft drink. Hydrate your kids. Keep them properly hydrated so they can go out and play. Fruits can be refreshing as a snack. Low-fat popcorn or pretzels are great; there are other ways of giving them snacks besides foods high in fat. Parents must model good eating habits for their children. They can’t just give them a bag of chips and sit them in front of the TV."

Eating a lot of fast food isn’t good for children either, Struempler says.

"However, if you have to eat a lot of fast food, make better fast food choices," she says. "Eat more salads, check the fat grams before you feed your child, and don’t eat a lot of French fries with your meal. Have a small burger with a side salad. That’s going to be healthier for your child. Stay active, make healthy choices, but more than anything, model good eating habits for your kids."

Even teenagers need guidance when it comes to making wise food choices. Struempler says the teenage years are a critical time for bone-building. Unfortunately, far too many teens drink soft drinks instead of milk and miss out on much-needed calcium.

"Teenagers are drinking soft drinks instead of milk for snack and dinner and everything else," she says. "Sometimes even school systems have a soft drink machine. If you consider that teenagers lay down about 45-50 percent of the calcium they need during those teenage years, and all they’re doing is consuming soft drinks – that’s damaging. And that damage will show up eventually, because they are going to live a long time. I really tell people if they don’t do dairy products it’s going to be very hard for them to get enough calcium, so they may even consider calcium supplements."

Not only are kids not eating nutritiously, they aren’t moving enough either.

Dr. Robert Keith, Extension nutritionist, says kids today are much more sedentary than their parents were at their age.

"Fifty years ago, kids played games – they played football, played basketball," he says. "Now they play at games on the video – they play basketball on the video, they play football on the video. So they used to play outside and get all this exercise. Now they’re getting, in a sense, the same mental gratification of playing these games, but there’s no physical aspect to it. People really have to make a conscious effort to be physically active in addition to whatever they have at work or at school."

Kids need to spend more time engaging in physical activity and less time sitting in front of a television set, he says. At least 30 minutes of cardiovascular exercise, such as walking, jogging or riding a bicycle, five or six times a week will help kids lose weight and get healthier.