WEDNESDAY, Nov. 19, 2014 (HealthDay News) -- New federal mandates controlling the types of meals served at U.S. schools may actually promote eating habits tied to obesity and diabetes, a new study suggests.
Although it's now required that school meals contain less fat and more whole grains, fruits and vegetables, there are no rules on added sugar or extra carbohydrates, researchers from Johns Hopkins Bloomberg School of Public Health explained.
The researchers found schools are mainly serving processed whole grains, which are easily converted into sugar during digestion. Meanwhile, many schools are serving canned fruit, fruit juice and flavored milk, items that contain added sugar, the study found.
The study's authors said that expanding federal school meal rules to include an increase in the amount of whole grain and whole food products served, as well as limits on added sugar and processed foods, could help ensure kids are eating the right carbohydrates.
They also recommended that an independent panel of experts reevaluate school meal restrictions to ensure saturated fats are not being replaced with processed carbs.
"The low-fat craze in the last two decades has caused Americans to transition to a high-carb, low-fat diet," said Sadie Barr, a student in a joint MPH-MBA program at Johns Hopkins University's Bloomberg School of Public Health and the Carey Business School in a Hopkins news release.
"This [change] has been strongly linked to obesity, diabetes and other diet-related diseases, in large part because the majority of the carbs we have been eating are processed. School lunches, even with these new regulations, still largely reflect this diet," Barr said.
School meals have significant implications for children's health. More than 30 million children participate in school breakfast and lunch programs, according to the researchers. That means school meals may account for more than half of the calories those children consume daily, the researchers said.
The Healthy, Hungry-Free Kids Act (HHFKA) -- passed in 2010 -- extended already existing rules about healthier school meals to students in all grades.
The newer law requires school meals to consist of 51 percent whole grains, according to the researchers. The legislation also requires that more fruits and vegetables be offered to students. Meanwhile, the saturated fats found in school meals must be limited to less than 10 percent of total calories. Students must only drink 1 percent or fat-free milk. Flavored milk must be fat-free, the researchers reported.
For the study, Barr and her colleagues examined the new school regulations and compared current school meals with the foods served to students in the school year beginning in the fall of 2009. They also analyzed the group of schools that had already voluntarily established healthier food programs.
The study, scheduled for presentation Tuesday at the American Public Health Association's annual meeting in New Orleans, showed the lunches served at schools that chose to adopt the healthier meal standards contained more than 54 percent carbohydrates -- slightly more than schools that didn't participate in the voluntary program. These carbohydrates were mostly processed. These meals, the researchers noted, are very similar to the meals now served under the new federal requirements.
"The one thing I found shocking is that the HHFKA regulation requirements make no mention of carbohydrates. The word 'fat' is mentioned perhaps hundreds of times. But the word 'carbohydrate' is not mentioned once," said Barr. "They didn't recognize that primary macronutrient. Requiring grains served to be at least 51 percent whole is a step in the right direction, but isn't enough to ensure that the meals served will be more whole and less processed, which would be more advantageous to health."
The U.S. Department of Agriculture provides more information on child nutrition programs.