By Dr. Mallika Marshall

BOSTON (CBS) – According to a study in The BMJ, school-based obesity intervention programs for young children may not help that much.

Researchers looked at a year-long program for about 1,200 five- and six-year-olds at more than 50 state-run schools in England and found that the body mass index (BMI) scores for the children had not changed significantly by the end.

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There were also no significant differences in the amount of calories consumed, levels of physical activity, or blood pressure.

The program included 30 minutes of physical activity at the end of each day, cooking classes for parents and children as well as educational materials.

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Critics say there were some problems with the design of the study, but the researchers say their results suggest schools cannot lead the charge when it comes to weight loss or obesity prevention in young kids.

Schools can certainly have a positive influence and reinforce healthy behaviors but can’t do it alone, they say.

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Good habits need to begin at home supported by positive messaging in the community, in the media and by the food industry itself.

Dr. Mallika Marshall