Even though we know what we need to do to stay fit, staying healthy is a battle against endless temptation.
Should government have a say in keeping us healthy? New York City's health commissioner Dr. Thomas Frieden is in the middle of that debate. He's become nationally known for campaigns like one leading to a restaurant ban on artificial trans-fats, an ingredient linked to heart disease.
"We think that this will save hundreds of lives each year," he told Early Show medical contributor Dr. Emily Senay. "Interestingly, most of the chains took it out nationally. So it's had a national impact."
According to the most recent statistics from the Centers for Disease Control and Prevention, heart disease is the single biggest cause of death in the United States; cancer is second, followed by stroke, lower respiratory disease, accidents and diabetes.
As of early this year, about one adult in four is obese. That's down slightly from last year. And smokers are scarcer than they were ten years ago. A quarter of Americans smoked in 1997 and fewer than a fifth do today.
Dr. Frieden believes those statistics can get even better. His anti-tobacco commercials make even jaded New Yorkers take notice. And that's just part of the fight. Under Frieden's watch, New York has banned smoking on the job, and in restaurants and bars.
"We are not taking away anybody's freedom. We are protecting the freedom of the workers in the workplace," Mayor Michael Bloomberg said of the ban.
The ban has even made waves across the ocean. France, where cigarettes and wine go hand-in-hand with the good life, now has a similar law - as do some 20 states and more than a dozen countries.
"The fight for the smoke-free air act in New York City was not easy," Frieden said. "Although most people favored it, those who didn't were much louder than those who favored it."
Among New York smokers left out in the cold is Audrey Silk.
"Why do you have to make sure that I conform to your way of life?" she said. "I don't understand it."
When she's not rolling her own cigarettes, the former city cop is a vocal opponent of Frieden's bans. How vocal? She's founded a group called CLASH (Citizens Lobbying Against Smoker Harrassment) to fight smoker harassment.
"One day at six o'clock in the morning, the alarm will go off and you will all have to go to the middle of the street and do push-ups," she said. "Because apparently, they've determined that our bodies belong to the states."
But Frieden says it's an issue of life and death.
"And even though someone may say, 'Hey, I'd rather smoke in a restaurant,' your right to swing your fist ends at my nose," he said. "And your right to exhale carcinogens doesn't extend to my work place."
Needless to say, he doesn't smoke, and his diet would make most vegetarians green with envy.
But he's quick to say he is not perfect.
"I have a real sweet tooth," he said. "So what do I do? I limit what I eat. If I were left to my own devices, I'd have a whole pie."
But there's no limit on how he wants to change what New Yorkers eat. He wants fast food restaurants to post calories on their menus, right up there next to the price.
"It's very clear that people want the information," Dr. Frieden said. "Many people - not everyone, but many - will change what they do based on it. The bottom line here is, how can you save the most lives?"
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