Hadley Malcolm

USA TODAY

The U.S. has a confused consumer epidemic — more shoppers are seeking foods labeled "natural" despite not fully understanding what the claim means.

The percentage of people who regularly buy food labeled natural has grown from 59% in 2014 to 62% in 2015, yet confusion abounds, according to research out Wednesday from Consumer Reports. The study shows the majority of people don't know what they're paying for when it comes to natural labels. At the same time, pressure is mounting to define a term that's never been legally regulated.

At least 60% of people believe a natural label means packaged and processed foods have no genetically modified organisms, no artificial ingredients or colors, no chemicals and no pesticides, according to the study by Consumer Reports. And 45% think that natural is a verified claim. It's not.

In fact, none of those attributes is necessarily true, because use of the word is not regulated. At least, not yet.

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The report comes as the Food and Drug Administration takes a closer look this year at how the term is used, whether it should be defined and how. A public comment period is taking place through May 10, according to the FDA site.

"Natural" is a seemingly straightforward word that's taken on an increasingly confounding meaning as our food preferences and definition of health evolve. The FDA does not formally define the word, meaning its use isn't regulated by any law. A "longstanding policy" interprets it to mean nothing artificial or synthetic has been added to a food that wouldn't normally be expected in that food, according to the FDA website. But the policy isn't intended to address food production, processing or manufacturing methods.

Organizations, including Consumer Reports and the Grocery Manufacturers Association, have been urging the FDA to define the term in recent years, as shoppers have moved away from processed and packaged foods and food companies have pledged to phase out artificial ingredients.

The lack of federal oversight, some say, is leading shoppers to make value-based decisions that end up being meaningless.

"The problem with having all these misleading labels is it creates a lot of green noise in the marketplace," says Urvashi Rangan, director of food safety for Consumer Reports. "If we think about wanting better food-production systems, then we need to provide meaningful choice to people."

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Adding to the complexity of a potential national standard is the fact that what shoppers consider meaningful food purchases now includes a long list of health, safety and sustainability attributes. We're no longer buying solely based on taste and convenience, according to a report out this week from consulting firm Deloitte, in partnership with the Food Marketing Institute and Grocery Manufacturers Association.

So shoppers are on the lookout for certain words, and use them as purchase signals regardless of whether the claims are regulated or not, says David Just, a professor of behavioral economics at Cornell University.

"If there’s a health claim on the front of the package, that’s what we zero in on," he says. "They’re interpreting those as, 'This is going to have some different impact on the way my body functions after I eat it.'"

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Consumer Reports calls out seven products with "natural" claims that also contain artificial ingredients or chemicals, including a Kraft shredded cheddar cheese with cellulose powder and Del Monte fruit cups that contain artificial preservatives.

"They’re trying to capitalize on a market where they know consumers want these things," Rangan says. Del Monte did not respond to a request for comment. Responding on behalf of Kraft, an official with the International Dairy Foods Association said that natural cheese is a term that's "been used for decades to distinguish these types of cheese from pasteurized process cheese."

Ingredients like cellulose powder "are commonly used and approved for use in a variety of natural cheeses," said Cary Frye, vice president of regulatory and scientific affairs for the association.

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Due to the range of interpretation, though, defining the term "natural" may prove a challenging, if not elusive, task.

"From a food-science perspective, it is difficult to define a food product that is 'natural' because the food has probably been processed in some way," says Lauren Kotwicki, a spokeswoman for the FDA. Pointing out the potential to split hairs, Just says all food at the grocery store passes through human manipulation at some point, even if it's just that a human planted the seed.

It's not as if we're buying "naturally-occurring wild carrots or something," he says. "It’s really hard to come up with a definition that’s both intuitive and actually meaningful to the consumer."

Follow Hadley Malcolm on Twitter @hadleypdxdc.