People buy more soda when they are offered packs of smaller drinks instead of single servings of different sized drinks.
The finding came from a new study published in the journal PLOS ONE and was conducted by a team of experts, led by Brent M. Wilson, from the University of California, San Diego.
People who regularly consume sugary drinks are genetically more vulnerable to becoming obese or overweight, a study showed in 2012.
Obesity is a serious problem in the U.S., and in an effort to fight this rising epidemic, a measure was passed by New York City that restricted the sale of sugary drinks larger than 16 ounces.
The experts explained:
"The restriction, however, would not prevent larger-sized drinks from being sold as bundles of smaller-sized drinks... Previous work has shown that mandates intended to improve eating habits may have the unintended consequence of increasing consumption"
The investigators wanted to analyze the outcomes of limiting surgery drink sizes on people's soda consumption. They did so by offering participants three different menus.
One hundred undergraduate students from the University of California participated in the study - 76 of them were female and the average age of all subjects was 20.
The three menus given to participants included:
one menu which offered 16, 24, or 32 ounce sized individual drinks
a second menu which offered a 16 oz. drink, bundles of two 12 ounce drinks, or two 16 ounce drinks
a third menu which offered only individual 16 oz. drinks
When the volunteers made selections from these menus as they would in a fast food restaurant, more soda was purchased from the menu that offered packs of 12 oz. or 16 oz. drinks than when they were offered individual sodas of different sizes.
After observing the choices the subjects made, the researchers discovered that total business revenues increased when menus offered packs of drinks instead of just small sized drinks.
When drinks sizes are limited, the researchers explained, businesses may have a strong motivation to offer packs of many small drinks instead of just individual portions.
The results indicate that restricting larger servings of sugary beverages in an attempt to help people control portions has the opposite effect.
"Our research shows the New York City ban on large-sized drinks may have unintended consequences that policy makers need to consider. Sugary drinks are a major source of business revenue, and businesses will adjust their menus in order to maximize profits."
In order to help the fight against obesity in the UK, doctors are calling for a tax on all sugary soft drinks, a report from February of this year revealed in NEJM.