Though constant steps have been taken to keep elementary students away from unhealthy and dangerous beverages, newer outlets and vending machines seem to pop up from nowhere, U.S researchers have found.

They have noted that over a three year period ending in 2009, more number of students have been exposed to sweetened beverages like sodas, higher-fat milk and sports beverages from stores at their schools. They feel removing such beverages could help fight obesity better.

"Elementary school students are still surrounded by a variety of unhealthy beverages while at school," said Lindsey Turner of the University of Illinois at Chicago, whose study appears in the Archives of Pediatrics and Adolescent Medicine.

"Sugar-sweetened sodas have been linked to childhood obesity. Because kids spend so much time in school, getting those beverages out of school should be a public health priority in our opinion," Turner said in a telephone interview.

U.S. elementary school administrators were mailed enquiring about students’ accessibility to high-calorie beverages over 2008 and 2009.

Researchers noted that number of vending machines however remained stable, over the three years, but access to stores rose unbelievably. By 2009, 61 per cent of them bought such drinks from vending machines as compared to 49 per cent, two years before.

"What we found was over time there was not a substantial decrease in sugary beverages, which is what we would have hoped to see," Turner said."We also found that school stores become more common, as did a la carte lines in lunch rooms."

Overall, she said 45 percent of public elementary school students could purchase some sort of beverage outside of the government meals program that did not meet national recommendations. That figure rose to 58 percent of students in private elementary schools, Turner said.

According to the American Heart Association, too much sugar often has harmful effects, and those that consume more sugar are more prone to strokes and diabetes. The association urges Americans to drastically cut down on sugar.

"I think at this point there still is a discrepancy between what we are actually recommending for children and what they are consuming," Dr. Alice Lichtenstein, a heart and nutrition specialist at Tufts University, said in a telephone interview.

The White House has in the past tried to support the cause of reducing childhood obesity. First Lady Michelle Obama this year issued 70-point plan to reduce childhood obesity.

The Center for Science in the Public Interest, a nonprofit health advocacy group based in Washington, urged Congress to pass the U.S. lawmakers to pass the Healthy, Hunger Free Kids Act when it returns for the lame duck session.

That bipartisan bill passed the Senate unanimously in August and includes a provision to get junk food and soda out of schools.