April 7 (HealthDay News) -- Schools that serve healthier foods, offer nutrition education and reward students for nutritious eating habits can make a major difference in preventing childhood obesity, according to a Temple University study.

Schools that implemented such a multifaceted nutrition program reduced the number of overweight children by 50 percent, the study, published in the April issue of Pediatrics, found.

"The increasing prevalence and serious consequences of childhood obesity have pushed us to find solutions that go beyond the clinic and reach greater numbers of children," lead author Gary Foster, director of Temple's Center for Obesity Research and Education, said in a prepared statement. "We focused on school, because children spend most of their lives there and eat at least one if not two meals there."

In the study, five Philadelphia schools introduced a School Nutrition Policy Initiative that included:

• Eliminating less healthy snacks and sodas available at school or replacing them with better options, such as water, low-fat milk or 100 percent fruit juice.
• Training teachers to teach about nutrition and giving students 50 hours of nutrition education during the year.
• Rewarding kids with raffle tickets to win prizes when they practice healthy snacking.
• Encouraging parents and students to purchase healthy snacks outside of school, and challenging the kids to eat better and be more physically active.

Over the course of two years, researchers followed students in grades 4 through 6 at these schools and five control schools, measuring the weight, height and physical activity of all 1,349 study before and after the study period.

Only 7.5 percent of students in schools with the new nutrition policy became overweight, compared with 15 percent of student who became overweight in the control schools. The nutrition policy appeared even more effective in preventing black students from becoming overweight when comparing the two groups of schools.

Despite the success, researchers expressed concerns that some students in School Nutrition Policy Initiative schools still gained weight. They suggested that stronger or additional interventions are needed, such as increasing physical education time, instituting more aggressive nutrition policies, and finding ways to change the nutrition environment outside of schools.

The researchers also recommend that prevention programs begin even earlier than fourth grade, as the prevalence of overweight children in grades 4 through 6 is already at 41.7 percent.

SOURCE: Temple University, news release, April 7, 2008