As many school districts across the country implement initiatives that ban the sale of junk food and promote the intake of healthy foods, a new study suggests that these strategies may be ineffective and unnecessary.

Nutritionists at Pennsylvania State University tracked the body mass indexes of 19,450 students from fifth through eighth grade and they could find no correlation at all between obesity and attending a school where sweets and salty snacks were available.

The research included analysis on students in schools where junk food was sold and in schools where it was banned, writes Nicholas Bakalar at the New York Times.

Jennifer Van Hook, the lead author and a professor of sociology and demography at Penn State, said:

“Food preferences are established early in life.

“This problem of childhood obesity cannot be placed solely in the hands of schools.”

This comes after the implementation of the Healthy Hunger-Free Kids Act, which aims to improve the quality of meals served to students in the nation’s cafeterias.

However, officials from school districts from across country roundly criticized the proposed guidelines as many states face extensive fiscal difficulties.

“The cost of complying with the regulations could go as high as $6.8 billion, with $4.1 billion of that covering the additional expense of school breakfasts. The federal government will provide only $1.6 billion in additional funding on implementation, so many districts will be forced to raise meal prices to cover the rest.”

Critics also pointed out that the new restrictions on starches and salt content will make it difficult to produce meals that meet the standard and still be delicious enough for students to enjoy.

Sally Spero, San Diego Unified School District’s food planning supervisor said:

“I know this is well-intended. I’m concerned about unintended consequences: That schools would stop serving breakfast because it would be too expensive, or that kids would stop eating lunch because it doesn’t taste good.”

The study, which suggests that these programs may be ineffective, is thought to give greater weight to these concerns.