(AP) -- For seven years, Dr. Thomas Frieden has been the nagging conscience of the nation's biggest city, the man who made sure New Yorkers couldn't smoke in bars or eat french fries cooked in artery-clogging trans fats.
Now, the city's health commissioner will be taking his crusade against unhealthy living national as the head of the U.S. Centers for Disease Control and Prevention.
President Barack Obama announced Friday that he has picked the 48-year-old Frieden to lead the public health agency, where he will be faced with some immediate decisions on how to deal with the swine flu outbreak, including whether to produce a vaccine. Frieden also may play a role in health care reform.
The selection reunites Frieden with an agency where he worked as an infectious-disease detective at the beginning of his career.
New York's health commissioner is not usually a household name, but many New Yorkers quickly got to know Frieden after his appointment in 2002, when he began a series of not-so-gentle campaigns to get the city to live healthier.
In 2003 he pushed through a ban on smoking in almost all workplaces, a rule that instantly transformed nightlife in the big city.
Big increases in cigarette taxes followed, aimed at making the habit so expensive people would give it up. This spring the average price of a pack in New York topped $9.
Smokers were outraged, but the backlash was short-lived and the city claims the effort is working: About 350,000 fewer adult New Yorkers smoke now than in 2002.
"There is probably nothing any person will ever do to save as many lives as that one act of our legislature getting together here in the city and passing the smoking ban, and Tom deserves the credit," Mayor Michael Bloomberg said Friday.
Frieden followed that up with a pair of new rules aimed at obesity.
One banned restaurants from cooking with artificial trans fats, substitutes for natural fats such as lard. Fast-food companies all over the country wound up altering their recipes. Even McDonald's had to change the way it cooked french fries.
The city also began requiring thousands of chain restaurants to post the calorie content of their foods on the menu, saying diners deserve to know before they order that a blooming onion can have four times the caloric punch of a Whopper.
Critics complained that he was fostering a nanny state and infringing on privacy rights.
"This is like no-fun city," one smoker complained.
Frieden is unapologetic. Illnesses such as heart disease, he said, are now leading killers, cost taxpayers billions of dollars, and should be treated with the same urgency as an outbreak of a contagious illness like tuberculosis.
In a 2004 editorial in the American Journal of Public Health, he chided most public health agencies for being "asleep at the switch" on chronic disease.
"Local health departments generally do a good job of monitoring and controlling conditions that killed people in the United States 100 years ago," while doing little about modern-day threats like diabetes, he wrote.
It is unclear how Frieden's approach will play in the rest of America.
His support of needle exchange programs and condom distribution to help prevent the spread of AIDS (he distributed tens of millions of free condoms, proudly stamped with the city's NYC logo and the slogan "Get Some!") may not sit well with conservatives.
Civil libertarians have chafed at his attempts to force changes in our diets, including, most recently, a push to get restaurants to use less salt.
New York magazine's Web site greeted the news of Frieden's appointment with the headline, "Health Commissioner Thomas Frieden to Take Fun-Hating National."
The Center for Consumer Freedom, a group funded by restaurants and food companies, put out a statement decrying his selection, saying he was "an overzealous activist who doesn't give any consideration to the importance of personal responsibility or privacy."
But public health advocates praise Frieden as someone who lets science, not politics, guide his decision-making.
Jeff Levi, executive director of Trust for America's Health, called him someone "who has the courage to shake up the status quo if science and evidence show that change needs to happen."
News of Frieden's appointment came as he was dealing with a flare-up in the swine flu virus in several city schools.
Thousands of people have become ill in the past few weeks, but Frieden has been reminding citizens in televised briefings that this flu, so far, appears no more or less dangerous than the garden-variety strains that sicken people each winter.
The outbreak has allowed Frieden to call on some of his earlier experience. After graduating from Columbia University's medical school, he worked in the CDC's epidemiologic intelligence service, then led New York's attempt to contain the spread of drug-resistant TB in the mid-1990s.
Frieden spent five more years fighting TB in India before his appointment as city health commissioner.
He will begin at the CDC in June. His appointment does not require Senate confirmation.
©2009 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
Explore further: Penis transplant offers hope to victims of botched circumcisions