Summer may be a time to enjoy outdoor fun in the sun, but unfortunately for many children, it is a time when the lack of a regular routine results in them packing on extra pounds.

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"Sometimes, kids aren't in camp and they aren't doing anything but sitting around, eating the wrong foods and not getting enough physical activity," said Dr. Felicia Stoler, nutritionist and exercise physiologist with the New Jersey Dietetic Association. "It's important for parents to keep their children active. That doesn't mean sitting inside on the couch watching TV. That means getting outside, going to the parks, beaches or to any other venues where they are taking part in physical activity. New Jersey has many activities that kids can take part in that don't cost anything."

Federal health statistics find that about one-third of children and teens in the United States are either overweight or obese. Putting on extra weight can cause health issues later in life. A number of recently published studies found that weight gain accelerated among kids during the summer months, often in children who were already overweight. In one study, researchers found that children's body mass index growth was more than twice as fast during the summer months.

"For some of those kids, just having gym in school is just enough, and when school is not in session, they aren't getting that regular activity," Stoler said.

Summer is the perfect time to take advantage of the produce that New Jersey is famous for, according to Stoler.

"Get fruits and vegetables, don't drown them in butter or fry them and make good food choices while increasing physical activity," she said.