Candy, soda, pizza and other snacks compete with nutritious meals in nine out of 10 schools, a government survey has found.
Already plentiful in high schools, junk food has become more available in middle schools over the past five years, according to the Government Accounting Office, the investigative arm of Congress.
"Parents should know that our schools are now one of the largest sources of unhealthy food for their kids," said Sen. Tom Harkin, the Iowa Democrat who asked for the study.
Obesity among children and teenagers more than doubled in the past three decades, according to the government-chartered Institute of Medicine. Obese kids will become adults with chronic health problems, said Harkin, the ranking Democrat on the Senate Agriculture Committee.