Junk Food Bans Can't Ensure Healthy Eating

My latest Calgary Herald column looks at the junk food ban soon to be in place in Calgary Public Schools:

Much like the allegedly sinister foods we're aiming to vanquish from Calgary schools, perhaps sweeping bans could also find their way onto a list marked "choose least often."
The Calgary Board of Education is proceeding with a plan to rid public schools of junk food by the start of 2012. That will mean removing sugary and salty snacks from vending machines, and removing such offerings from school cafeterias. Catholic schools are removing junk food from vending machines next week.
However, for as much as this discussion revolves around schools and children, perhaps we should more precisely identify the target of such policies: high school students. The very same high school students who, in many cases, are holding down part-time jobs and driving themselves to school, or making preparations for post-secondary education. It is at the high school level where students typically have disposable income or are at the age where they are trusted enough to be sent to school with money, rather than a packed lunch.
Certainly, by the time a child reaches high school, nutritional patterns and eating habits are going to be fairly well established, and it's hard to see how these policies are going to have much impact.
Clearly, though, many expect the bans to make a difference. So far, the evidence is less than encouraging. For example, a study published in July in the American Journal of Public Health found that junk food bans in school did lead to a reduction in the consumption of soft drinks, particularly among certain minority groups. However, the same study found the bans led to no decline at all in students' body mass index.
A major study in 2009 by the non-profit RAND Corp. found that banning the sale of junk food in schools had no significant effect on BMI, had no significant effect on overall consumption of health food, and found no evidence of broader effects on behaviour or academic outcomes.
And what's to say these policies promoting healthy food actually lead to healthier eating? Surely juice is healthier than soda, but why are the 41 grams of sugar in a cup of grape juice more acceptable than the zero grams of sugar in a Coke Zero?
In a profile on celebrity chef Jamie Oliver - who has become a major activist for healthy food in schools - Reason magazine found that one of Oliver's own recommended "healthy lunches" contained more calories and fat than not one, but two McDonald's Happy Meals, including soft drinks.
There is also a financial side to all of this. For one, removing the products means losing that revenue. It seems to me that such additional revenues could help toward the availability and quality of physical education, which might make more of a difference than removing the snacks.
Secondly, will offering healthier meals in the school cafeteria make those meals more expensive? Will that mean an even greater burden on schools on top of lost revenue? Or will that cost be passed on to the students, making it even more likely they'll avoid such fare?
If a 17-year-old can find a way to cheaply satisfy his hunger, he'll do so. There's a reason Kraft Dinner is a staple of many high school and university students' diets.
One might still argue, however, that banning junk food sends "the right message." But does it? It seems to me that a policy devoid of any creativity and flexibility, and based on an inherent mistrust of teenagers, entails some poor messaging.
Indeed, a little flexibility and creativity could go a long way. Cornell University's Brian Wansink has done some fascinating research on how to guide young people toward healthier choices. For example, one study showed that by simply labelling carrots as "X-Ray Vision Carrots," young children consumed significantly more of them.
Wansink and colleagues also showed that by combining that approach with some changes in menu selection and the layout of the cafeteria, students will make healthier choices.
As they put it, "children can be presented healthy and unhealthy items and be led to willingly choose the good."
That's what we all want. But by simply removing junk food, we're ensuring it won't happen. Let's rethink the junk food ban.