Why Americans Need Bloomberg's Big Gulp Ban NYC's mayor wouldn't be trying to outlaw giant sugary drinks if we hadn't lost all sense of a normal serving size A woman holds a large soda on a street in New York, May 31, 2012. Brownlee's latest book is Overtreated: Why Too Much Medicine is Making Us Sicker and Poorer. Last week, New York city mayor Michael Bloomberg announced a plan to ban sales of sugary beverages larger than 16 ounces. The ban would apply to both bottled soda and fountain drinks containing more than 25 calories per eight ounces, but would exempt alcohol, fruit juice, or any beverage that's at least half milk. That means that the city's 20,000 restaurants, coffee shops, food carts, movie theaters, and stadiums will no longer be able to sell empty calories in supersize portions. MORE: The New York City Soda Ban, and a Brief History of Bloomberg's Nudges Bloomberg has gotten a lot of flack from the beverage industry and free marketeers, but he's right to propose such a ban: we shouldn't really be drinking anything out of those bathtub-sized cups but water, and certainly not a 7/11 Double Gulp that contains 55 ounces and more than 700 calories. But huge has become the new normal. The fact that such a ban is even being proposed shows you how out of whack our sense of proportion has become. 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. The same thing has happened with hot drinks. Remember the Starbucks 8-ounce "short" cup of coffee? That's not on the menu anymore. If you walk in and ask for a small, you get a 12-ounce "tall." Small is tall. MORE: Meet Big Soda - as Bad as Big Tobacco The reason for all this supersizing is basic economics. When you go to a McDonalds or Wendy's, the cost of serving you is pretty much fixed because what they have to spend on the food is almost negligible compared to what they pay for their workers and floor space. However, if they can get you to pay, say, 25 cents more for 5 cents worth of soda, the franchise owner earns a tidy profit and you walk out the door thinking you've gotten an absolutely fantastic deal by paying only a few extra pennies for a drink that's as big as your head. 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. MORE: Let's Stop Being Passive About Fighting Obesity 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. Critics point out that such a ban might be difficult to enforce, and they have a point. If you desperately want a giant soda while you watch a movie or ball game, nobody's stopping you from getting three drinks, or going out for refills. But you will have to think twice about it, pay more for it, and the people around you might just might start staring. Remember, smoking bans changed social norms by making smoking seem less acceptable. If that's what it takes to make a dent in obesity rates, let's hope other cities follow Mayor Bloomberg's lead. Brownlee, author of Overtreated, is acting director of the New America Foundation's Health Policy Program.