By Mike Pomranz
Updated August 28, 2015

According to a new study out of NYU, only about 20 percent of people correctly understand the meaning of a “serving size” on nutrition labels. Now some experts are speculating that this confusion is set to get worse with the FDA planning to implement changes to serving sizes on many foods next year.

For the record, a serving size is defined by the government as “an amount customarily consumed” (a definition that was not particularly easy to find via a Google search). Since the way people consume food has changed over the years (we’re eating more), changing labels to reflect these new “customary amounts” makes sense in theory. In fact, it’s the only way to keep serving sizes in line with their official definition.

However, rather than a reflection of how much they actually eat, many Americans believe that a serving size is a recommendation of how much they should eat. Owing to this misconception, experts fear larger serving sizes—like doubling a serving of ice cream from half a cup to a full cup—will actually increase the amount people eat.

Researchers in the NYU study found that larger serving sizes on nutritional labels regularly caused people to consume more and serve more to others. In one experiment, people given mini chocolate chip cookie packages marked with a serving size that had been doubled said they wanted to eat twice as many cookies as people who were given the original packaging. The research team found similar results when asking people about doling out Goldfish crackers or lasagna to others.

“Basically, in all those studies, we find that the increased serving sizes of the proposed label lead consumers to serve more product to themselves and others, which is potentially very troubling because excessive consumption is a key contributor to obesity," Steven Dallas, a doctoral student of marketing at NYU, who led the research, was quoted as saying. Harvard’s Behavior Science and Regulation Group agrees, warning that consumers might think these new serving sizes have been “endorsed.”

Of course, it’s also possible that having nutrition labels better reflect what people are really eating will serve as an eye opener for how many calories they are really consuming. Though if consumers don’t understand the meaning of a “serving size,” will they understand all the information listed below it?

[h/t Live Science]