Monday, June 4, 2012

Changing unhealthy habits requires changing environments

New York City Mayor Michael Bloomberg's recent proposal to ban sales of sugary beverages larger than 16 ounces has encountered opposition not only from soda manufacturers, but many others who are skeptical that such a ban would make any difference in the explosion in obesity rates. According to the Centers for Disease Control and Prevention, in 2010 the percentage of state residents classified as being obese ranged from 21% (Colorado) to a staggering 34% (Mississippi). By comparison, in 1990 no more than 15% of residents of ANY state were obese! But will banning the sale of extra-large sodas address this problem, the way that public smoking bans have helped to drive down smoking rates? In "Why Americans Need Bloomberg's Big Gulp Ban," TimeIdeas columnist Shannon Brownlee argues that the answer is yes:

When I was a kid, Coca-Cola came in 6-ounce glass bottles, and that seemed like plenty. It wasn’t all that long ago that a 12-ounce soda was considered perfectly sufficient—even large. But walk into any pizzeria or deli these days and you’ll have a very hard time even finding 12-ounce cans of anything. 20-ounce plastic bottles are now considered the standard single-serving size. ... As a result, we can no longer gauge what’s an appropriate amount of calories we should be drinking. The average American guzzles 52 gallons of soda, sweetened fruit juices, sports drinks, energy drinks, and sweetened tea and coffee per year. These drinks account for a third of the 156 pounds (pounds!) of added sugar each of us consumes on average each year. The ban on large drinks, on the other hand, could reset our notion of what a normal beverage serving looks like, and that could make all the difference. 

On the Washington Post's WonkBlog, Sarah Kliff reviews Bloomberg's accomplishments as a self-styled "public health autocrat": making NYC the first city to ban smoking in restaurants and bars, ban trans-fats in restaurant foods, and require chain restaurants to prominently post calorie count information. Numerous cities and states have since followed Bloomberg's lead, and the Affordable Care Act, if not struck down by the Supreme Court, will require calorie labeling at chain restaurants all over the country.

Critics argue that these well-intentioned initiatives infringe on freedom of choice and haven't been shown to improve health-related habits. For example, one study found that low-income people in NYC were no more likely to choose lower-calorie foods after the policy went into effect. This and other studies suggest that it takes more than data to affect food choices. After all, you may not know that a Big Mac with Cheese packs 704 calories and 44 grams of fat, but unless you're from another planet, you probably knew that it isn't good for you. On the other hand, when the Massachusetts General Hospital redesigned its cafeteria by implementing a simple color-coded scheme (red for unhealthy, yellow for less healthy, and green for healthy) and making healthy foods easier to see and reach, sales of healthy items (especially beverages) rose substantially. Changing the environment accomplished what calorie labeling couldn't.

Kudos to Mass General, but outside of deep-pocketed Harvard, where will the money come from to redesign hundreds of thousands of cafeterias? In the June issue of The Atlantic, David Freedman argues that obese and overweight people can change their microenvironments - and successfully change unhealthy eating and exercise behaviors - with the help of mobile technologies:

Today, for absolutely nothing, would-be weight-losers can download many of the key elements of a Skinnerian behavior-modification program directly to their phones and computers. One of the most popular options is Lose It, an app and Web site that allows users to pick a goal weight and a time line for reaching it, and then formulates a daily calorie count accordingly. Lose It then lets users track their eating and physical activity, which they can do by holding their phones up to a food package’s barcode, or by tapping the screen a few times at the start and end of a walk (the app offers a range of activity categories, including guitar strumming, household walking, and sex). Lose It uses this data to provide clear, graphic feedback on users’ daily progress—you might see at a glance that having dessert will send your numbers into the red, but that if you walk for 20 minutes after dessert, you’ll go back into the green.

As yet it remains uncertain if weight-loss apps will be able to replicate the results of more traditional, labor-intensive weight-loss interventions. And it's still reasonable to assume that strategies to stabilize, and eventually, reverse, national obesity rates will need to change obesity-promoting environments on the individual and community levels. The first step to a healthy weight may be disappointment at the inability to buy one's usual big sugary soda; the second one may be deciding, on second thought, not to purchase a soda at all.