Schools in Mexico have six months to implement a government-sponsored ban on junk food or face heavy fines, officials said Monday, as authorities confront what they call the worst childhood obesity problem in the world.

The rules, published on Sept. 30, target products that have become staples for two or three generations of Mexican school kids: sugary fruit drinks, chips, artificial pork rinds and soy-encased, salty peanuts with chili.

School administrators who violate the order will face fines equivalent to between $545 and $5,450, which could double for a second offense. That could amount to nearly a year’s wages for some.