Portion Sizes

My many friends who are doctors have long told me, “There are two things that are definitively and conclusively bad for you: smoking and obesity.” But unlike smoking, which is a fairly straightforward proposition (don’t smoke or be around smoke), tackling obesity is far more complicated, as an excellent special report in The Economist points out. In general, I agree with economists that the best way to encourage a decrease in consumption is through an increase in pricing; however, it’s hard to decide which calorie and form of calorie can be efficiently taxed to make a positive impact on obesity rates. Therefore, I support a piecemeal approach where, rather than tackle “the calorie” as an aggregate unit, we target sub-categories of calories. Specifically, I support the restriction of portion sizes for beverages that exceed a certain caloric threshold.

Mayor Michael Bloomberg took a lot of flack for restricting portion sizes for soft drinks in New York City. Many complained of paternalism or the nanny state, and saw it as an unnecessary incursion into personal liberties, as well as imposing onerous execution costs on store owners. I tend to be wary of reactive government intervention that seeks to score political points at the expense of effective action; but, as with the ban on smoking that changed social norms around smoking (contrast the atmosphere of Mad Men with how you might react today when you see a colleague sneak off for a  smoke), I believe this is a good step towards nudging consumers in the right direction for calorie management and consumption.

What solidified my support of Bloomberg’s plan was an unintentional experiment I ran on myself. I have been trying to drink more water - 8 8oz cups a day. I’m lucky enough to have a great water dispenser at my office. But I found I repeatedly missed that mark, drinking, at most, 4-5 cups a day. Then, I started bringing a 32oz Nalgene to work. I filled it once in the morning, once after lunch and voila - I have no problem drinking 8-10 cups a day. That simple. Nothing changed - my daily routine, my diet, my exercise - except for the size of the vessel I was drinking out of. While this is n=1, it’s indicative of human behavior - we eat (or drink) what we’re given. In the aggregate, it’s unlikely for every consumer who is forced to switch from 32oz of beverage to 12oz of beverage to replace those oz by purchasing a second or third beverage.

The impact of reducing your intake of sugary beverages is huge. Imagine if 20oz sodas were unavailable, and you had to make do with 12oz cans. Further assume that you drink two 20oz sodas a day. Saving 16oz of soda a day translate into 186 fewer calories per day. That’s one pound every 2.5 weeks or 20 pounds in a year! Even if you decide to add a third beverage to compensate, you still save 4oz of soda per day or 5 pounds per year. And, unlike the difficultly of effectively  substituting fruit for cheese or fish for beef, or an English muffin for a bagel, consumers are unlikely to face a trade-off with soda (or juice). It’s simply drink more or drink less, largely driven by how much is in front of you at any given time.

So kudos to Mayor Bloomberg and, as with the ban on smoking that eventually became de rigueur around the country, I hope that other cities and towns take note. A journey of a thousand steps just might begin with a smaller cup.