Researchers say that poor eating habits and a lack of exercise start as early as when children move from preschool to elementary school.

Parents reported that children had relatively good eating habits and physical activity levels from ages 2 to 5, but parents of 6- to 12-year-olds said their kids had less healthful diets and leisure-time activities.

The results came from a study of 184 children by researchers at the University of Tennessee.

Parents of older children said they drink more sweetened drinks and salty or sweet snacks. They also ate with parents less often.

The older children also watched significantly more TV on weekends than the younger ones, according to a news release on the study, which did not give specifics on the differences.

Author Dr. Hollie A. Raynor said that not all the news was good for the younger children.

"Although preschool-aged children engaged in more healthful behaviors according to parent recall, the preschool-aged children only met two dietary recommendations, fruit and low-fat dairy intake. All other parent-reported eating and leisure-time activity patterns did not meet current recommendations," she wrote. "Surprisingly, other than fast-food consumption, this study found few parent-reported eating and leisure-time behaviors related to weight status, which may be a consequence of the overall poor diet quality and relative inactivity reported in this diverse sample."

The study was published in the January/February 2009 issue of the Journal of Nutrition Education and Behavior.