NEW research by psychologists at the University of California-San Diego indicates that the ban on large sizes of sugar-sweetened drinks that was passed in New York City earlier this year -- but found illegal -- almost certainly would have backfired.
The ban actually would have encouraged people to buy more soda and consume more calories than they would have without the restriction, according to the research, which was published in a Public Library of Science journal.
It also would have encouraged purveyors to "bundle" drinks to increase revenues, according to the research.
The ban was proposed by New York City Mayor Michael Bloomberg and enacted through the New York City Board of Health, all members of which were appointed by Bloomberg (Feedstuffs, Oct. 1, 2012).
It would have prohibited delis, restaurants, street carts, movie theaters and sports stadiums from serving sugary drinks in containers larger than 16 oz. It defined "sugary drinks" as those with more than 25 calories per 8 oz.
However, a coalition of beverage, restaurant and theater interests sued to block the ban's implementation, and New York Supreme Court Judge Milton Tingling granted the injunction last month (Feedstuffs, March 18).
The California psychologists recruited 100 students at the university and set up a concession stand offering pizza, popcorn and sodas, the latter in bundled and single-serving options.
In one trial, the students could choose 16 oz., 24 oz. or 32 oz. drinks for $1.59, $1.79 and $1.99, respectively.
In a second trial, the students could buy one 16 oz. drink for $1.59, or they could choose from a bundle of two 12 oz. drinks for $1.79 or two 16 oz. drinks for $1.99.
In a third trial, the only choice was a 16 oz. drink for $1.59.
The researchers said students ordering from the bundled menu bought more ounces of soda than in either of the other two options (Figure 1). In addition, they said the concession stand's revenues were significantly higher when bundled drinks were offered (Figure 2).
David Just, an economist at Cornell University who was not involved in the California study, said the findings fit with natural behaviors.
Most people preparing to buy a soda will buy the regular size, he said. However, when people are prevented from exercising choice, "they're going to display 'reactance' -- a determination to circumvent the policy."
Most vendors "are all too willing to comply" with that attitude, he said.
The study is available at www.plosone.com.