CHICAGO (CBS) – Lawmakers in San Francisco made headlines this week for their ban on providing toys with the McDonald’s Happy Meal.

But now in Chicago, an advocacy group has issued a call to go a step further than even that.

The Washington, D.C.-based Physicians Committee for Responsible Medicine, which advocates vegan diets, issued a letter to Mayor Richard M. Daley Thursday. The group is calling for a moratorium on the construction of new fast food restaurants in Chicago.

In the letter, Susan Levin, the group’s director of nutrition, called for Mayor Daley to declare a “public health emergency” and “work with the City Council” to ban new fast food restaurants.

“This step is urgently needed because Chicago’s high-fat, meat-heavy diets are literally breaking hearts,” Levin wrote. She went on to quote the Illinois Department of Public Health as saying cardiovascular disease killed almost 8,400 Chicago residents in 2003.

The letter said the group conducted a survey of the six largest cities in the country, and found Chicago has the second highest number of fast-food restaurants per capita, behind Houston. The survey indicated that even Los Angeles has only two thirds as many McDonald’s store as Chicago despite having a larger population, the letter said.

In 2008, the city of Los Angeles placed a moratorium on new fast food restaurants in low-income neighborhoods with high obesity rates and already high concentrations of such businesses.

The Physicians Committee for Responsible Medicine urged Mayor Daley to do the same for the whole city.

“It’s time to tackle Chicago’s heart disease problem head-on. A moratorium on new fast-food restaurants could be a critically important step in fighting this epidemic,” the letter said. “Please move quickly – lives depend on you taking swift and decisive action to improve Chicago’s eating habits.”

The Physicians Committee for Responsible Medicine promotes an end to animal research, preventive medicine, and a vegan diet.

In September, the group made headlines – and infuriated McDonald’s – with a commercial that openly blamed the Oak Brook-based fast food chain for causing “high cholesterol, high blood pressure (and) heart attacks.” The ad showed a deceased man lying under a sheet on a mortuary trolley, with a half-eaten “Big Mac” still in his hand.

The commercial mocked McDonald’s slogan, saying, “I was lovin’ it,” and told viewers, “Tonight, make it vegetarian.”

McDonald’s blasted the ad, which was produced for the Washington, D.C., market.

“This commercial is outrageous, misleading and unfair to all consumers,” McDonald’s said in a statement in September. “McDonald’s trusts our customers to put such outlandish propaganda in perspective, and to make food and lifestyle choices that are right for them.”

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