Mayor Thomas M. Menino is casting doubt on discussions to banish unhealthy fats from restaurant kitchens, saying it would be difficult for Boston to enforce a ban similar to the one recently enacted in New York City.
The mayor said last week that battling obesity ranks among his leading public health priorities, but in an interview he questioned whether a ban on ingredients known as trans fats was the best way for the city to contribute to that fight. For a prohibition to be meaningful, Menino said, it must be easily enforceable.
"We in government a lot of times say we're for things, but how do we monitor" a ban on trans fats, the mayor asked.
A restaurant "could have a sign that says 'We have no trans fats,' " Menino said. "But do we have enough inspectors in the city to go around and inspect these places?"
New York's health agency this month ordered restaurants to eliminate trans fat, a substance linked to higher rates of cardiovascular disease. The measure inspired health agencies across the nation -- including the Boston Public Health Commission -- to consider adopting similar bans.
Last week, John Auerbach, Boston's top health official, traveled to New York to meet with his counterpart there to better understand how the city made its decision to ban trans fat and how it intends to enforce the rule.
Auerbach said in an interview that he has had only preliminary discussions with Menino about a ban.
The mayor's support would be crucial: Menino, both as mayor and, earlier, as a city councilor, has championed an array of often controversial health campaigns.
In the 1990s, he successfully advocated for a needle exchange program in the city to prevent HIV and hepatitis transmission. More recently, he withstood the taunts of tavern owners as he led the effort to prohibit smoking in bars and restaurants.
Trans fats, which are usually artificial, have been shown to increase the bad form of cholesterol and, by extension, the risk for heart disease. The fats are commonly used in commercially produced cakes, cookies, pies, margarine, and fried foods.
Typically, they are used to extend shelf life, and some chefs say they enhance the texture of certain food.
With so few successes in the effort to shrink the nation's bulging waistline, public health authorities have seized on banning trans fats as a way to attack medical conditions associated with obesity.
"These trans fats are killing us and, ultimately, these things are on the way out from kitchens," said Geoffrey Wilkinson, executive director of the Massachusetts Public Health Association, a confederation of local and state health officials.
State Representative Peter J. Koutoujian, a Waltham Democrat and chairman of the House Committee on Public Health, has filed legislation that would ban trans fats statewide. But the proposal by Koutoujian does not dictate how a prohibition would be enforced, leaving that up to cities and towns.
During his visit to New York, Auerbach explored the intricacies of how New York intends to monitor its rule, which will be phased in starting in July.
He won a pledge from Dr. Thomas R. Frieden, New York's public health commissioner, that Boston authorities can attend training sessions for New York restaurant inspectors who will be responsible for tracking down trans fats.
Auerbach said that he shares the mayor's misgivings about enforcement, but that the trip to New York -- which also took him to a doughnut factory that has abandoned trans fats -- proved enlightening.
"I was kind of thinking they would need to go through cupboards and look for small amounts of margarines or other oils that might have trans fat," Auerbach said. "But they were more inclined to be looking for the large containers of trans fat oil --the kinds that would be used for frying or in large quantities that are very clearly marked."
At some restaurants in Boston and New York, owners are already converting from trans fats to other, healthier ingredients.
Menino, for instance, had lunch one day last week at a fish restaurant that has forsaken trans fats. And Koutoujian knows of a popular spot in his hometown that has done the same.
Koutoujian predicted that "more restaurants will move in this direction, just because of the public debate."
Stephen Smith can be reached at email@example.com.