A version of this article originally appeared on Transportation Nation.

Subway and bus ads are the latest battleground between New York Mayor Michael Bloomberg’s health department and soda makers. The newly formed New York City Beverage Association is taking a huge mass transit ad buy as part of a $1 million campaign to rebut the city’s claim that soda is unhealthy.

For months, the city has been running public service announcements linking sugary drinks to mountains of fat and waterfalls of sugar, including a graphic video (below) that claims drinking a can of soda a day can add 10 pounds in a year by showing a man pouring fat out of a can of soda and drinking it.

Health Department Commissioner Thomas Farley elaborated on those objections in a statement to Transportation Nation: “Americans are literally drinking themselves fat, consuming 200-300 more calories daily than 30 years ago, with the largest single increase due to sugary drinks.”