Blue Cross and Blue Shield of Minnesota launched a pull-no-punches television campaign earlier this month that calls on overweight parents to look at their own food choices and own up to their part in raising pudgy children with equally poor eating habits.

In New York City, Mayor Michael Bloomberg has been lauded -- and skewered -- for using his bully pulpit to outlaw trans fat in restaurants and, more recently, to ban supersized sodas in theaters and fast-food joints.

Barbara Loken is taking note of the shifting tides in the obesity fight. Loken, a marketing professor at the University of Minnesota's Carlson School of Management, is an expert in branding and consumer psychology.

She has spent decades studying how advertisers, the media, public health officials and laws can affect consumer behavior. She said many of the lessons learned in curbing smoking rates are being applied to the nation's obesity epidemic.

QYou sense that the time is right to make headway in addressing obesity. Why?

AThe perception is changing -- whether it's school kids getting more nutritious lunches, or putting a tax on soda. Look at what Bloomberg has done in New York. He's setting limits on the size of soda. That's something that never would have been done 10 years ago.

I used to go into my classrooms and talk about smoking literature. Students would say, "Oh yes, of course we needed the Clean Air Act. Airports and restaurants are so much nicer now." But if you asked them about regulating soda pop or any junk food, they'd say, "Absolutely not! You have to be able to have choice in what you eat." But this last year I asked my students, and a lot thought there should be a tax.

QWe're well aware of the obesity problem and what we're supposed to do about it. Why haven't these messages taken root?

AThese are deep-seated behaviors that are difficult to change. You can't just pound people with messages. The messages have to get people to a state of readiness, so that cessation programs or quit lines or Internet programs are more useful.

So if you're doing a campaign to get people to eat better, you have to make sure that the local grocery store has fruits and vegetables, or introduce little markets of your own. Then people are more likely to listen to the message and act on it. If you just give them the message and the food is unavailable or it's too expensive or unfamiliar, it probably won't work.

QHow do public health officials, the health care industry and others use marketing tactics to move people to action?

AIt's important to make the message top-of-mind. When I have a pedometer, I think about walking more.

Mass media -- TV, radio, billboards -- can work on its own, but it is more effective when combined with other elements, such as community programs, immunization in schools, free screenings and public policy.

There are studies that looked at states that used buckle-up campaigns without seat belt laws, and states that implemented the laws without the marketing. Each is less effective on its own than if you combine them.

Same with tobacco control. Taxes and public health messages had an impact, but even more important was the Clean Air Act. It just made it more difficult to smoke for much of the day.

QMany companies have spent money on wellness programs and money-back incentives to get people to lose weight, eat better, exercise more, stop smoking. Is there proof that these programs work?

AThat's a huge debate in all of psychology about what works better, rewards or punishment. Think about raising your kids. Is it better to punish them or reward them? Some people feel on the one hand it's better to spank and give a slap now and then. Others think, No, you should never do that. The same is true for incentives in the workplace. Some people are more receptive to rewards, some to punishment. There are certain contexts where rewards might be more effective. We need more research.

QWhat about concrete actions: putting in walking paths or building an on-site clinic?

AAnything you can do to make it easier for consumers to exercise and get healthy foods makes a huge difference. People may have good intentions to exercise, but there's no way to do it until they get home from work.

I worked on a health project at the [U of M] School of Public Health with Henry Blackburn, an internationally known cardiologist. We would be in meetings with people from the National Institutes of Health coming in, and about half the room was standing up or walking around. This was in the 1980s. They knew that it's better to get up and stretch and walk around the room. I hadn't ever seen that before or after.

QEven a good message can go wrong if consumers sense that a company's motives aren't sincere, right?

AResearch on corporate responsibility suggests that it's a good thing to tie your brand with a cause. A lot of consumers are skeptical, though -- there was a campaign in the United Kingdom, where PepsiCo sponsored an anti-obesity campaign, and it didn't work very well.

But if consumers are less familiar with the company, their ratings go up. So if Philip Morris does an anti-smoking campaign, some consumers might not even associate Philip Morris with cigarettes.

Jackie Crosby • 612-673-7335