NEW YORK (AP) – When Mayor Michael Bloomberg sat down to eat lunch with children during a school visit several years ago, he was disgusted by the soggy, greasy fries and other junk on their plates.

He directed his education commissioner to begin revamping school menus, and by the next fall, fat-laden meals were being replaced by healthier versions. That same year, 2003, the city began handing out free nicotine patches and the mayor won his crusade to outlaw smoking in bars and restaurants. Now the city is going after fatty foods in bodegas, restaurants and company cafeterias.

Experts say the health-conscious Bloomberg has targeted unhealthy lifestyles unlike any other administration before him.

“It’s more aggressive than we’ve ever seen in the past,” said Dr. Allan Rosenfield, dean of Columbia University’s Mailman School of Public Health. “There’s a willingness to take on unpopular but important issues.”

More than 53 percent of New Yorkers are overweight or obese — lower than the ballooning national 65 percent, but far too high, according to Bloomberg and his health commissioner, Dr. Thomas Frieden. An unhealthy weight increases the risk of diabetes, high blood pressure, cancer and heart disease, which is New York City’s worst killer.

Last summer, the health department launched a campaign against trans-fats. Often used by restaurants and in packaged foods, trans-fats are thought to cause cholesterol problems and increase the risk of heart disease.

After restaurant inspectors found that 30 percent of the city’s 30,000 eateries were using oils that contain trans-fats, the department began calling for a citywide “oil change.” Officials sent letters to food service establishments, and started training food handlers about trans-fats during their safety program on food-borne illnesses, which is required for all restaurants.

The city plans another survey this spring to measure the results of the project.

Officials next want to tackle portion sizes.

Towering pastrami sandwiches, bagels with gooey schmears of cream cheese and pizza slices that spill over paper plates may be the city’s culinary landmarks, but the health department says the Big Apple is out of control.

“Today probably the biggest hazards from what you eat are not food poisoning but the caloric load, so we’re trying to use the structure that we’ve developed over many years to monitor restaurants, to also reach out to them with education on how they can prepare food in a more healthy fashion for their clients,” said Dr. Lynn Silver, an assistant health commissioner.

Leaders of the state restaurant association — who opposed the smoking ban — have so far supported the health department’s dip into nutritional education, but are eyeing it cautiously.

“It’s one thing for them to recommend, it’s another if they start saying, ‘you must do this,'” said Charles Hunt, who heads the New York City office.

With nutrition, Bloomberg has so far stopped short of citywide measures as aggressive as the smoking ban. But his obsession with weight and eating should not be underestimated.

Bloomberg, who is 5-foot-8 and a former smoker, keeps a close eye on his own waistline. In 2001, he gained some weight during his first campaign and transition into City Hall, and was horrified when he saw an unflattering photograph of himself in the newspaper.

Aides said Bloomberg tacked the clipping next to his desk as inspiration to lose the weight, which he did.

The 63-year-old mayor runs for nearly an hour every day on a treadmill at his Upper East Side home. He limits himself from eating too many unhealthy takeout lunches, and consumes a lot of salads, often snacking on popcorn.

Bloomberg’s weaknesses are red wine, hot dogs and the occasional hamburger. If he overindulges, there’s a price to pay: He has a weight-loss wager with longtime friend Peter Grauer, the CEO of Bloomberg LP. They weigh in every six weeks, and whoever is over his goal weight — Bloomberg’s is 169 — must fork over cash to charity.

The mayor’s administration is also beginning a venture to change workplace nutrition. Officials are working with some of the city’s biggest employers, including Consolidated Edison and large hospitals, to shape up their cafeteria food and vending-machine snacks.

The health department is even cleaning up its own diet, and recently banned sugary junk like doughnuts and soda from the list of fare workers can buy for department meetings.

“We have been seeing a lot more fruit trays, vegetable trays, whole-wheat bread, healthy sandwiches — so we’re working on practicing what we preach,” Silver said.

Next week, the department is launching a drive to improve the offerings on the shelves of the city’s bodegas. These corner stores are often the primary sources for groceries in many neighborhoods, particularly in low-income areas, and officials have found that many of these shops don’t stock healthy staples like low-fat milk and fruits and vegetables.

The pilot program, which includes promotional posters, will push the sale of 1 percent milk at a handful of bodegas in Harlem, the South Bronx and Brooklyn.

City officials say the new focus on lifestyle health issues may be yielding encouraging results: In 2004, the number of deaths from heart attacks dropped significantly. And they say the number of smokers in New York City has dropped by nearly 200,000 since 2002.