More recently, these companies have faced lawsuits for inappropriate marketing. For example, the Center for Science and the Public Interest (CSPI) recently warned Kraft Foods that it would be sued for misleading advertising if it continued to market its Crystal Light lemonade and iced tea mixes as natural. Stephen Gardner, CSPI's director of litigation, estimates this is just one of 50 ongoing legal battles over the marketing of unnatural foods as “natural.”

The FDA has been problematically ambiguous on the issue, according to Gardner, but the website states the organization “has not objected to the use of the term if the food does not contain added color, artificial flavors, or synthetic substances.”

“The companies know what they’re going to get sued for, but that doesn’t stop them from trying,” he said.

For their part, Caroline Krajewski, a corporate affairs representative from Kraft, stated that “We believe all our labels comply with the law and are not misleading.” She cited a separate recent case brought against Kraft's Crystal Light iced tea and lemonade mixes for misusing the word natural that was dismissed by a federal judge in California.

This case is unrelated to CSPI’s warning, Gardner said. He added he believes Crystal Light’s violation is obvious — lemon flavor is plausible, but “there’s no such thing as lemonade flavor,” so it’s impossible to market such an item as a natural product.

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The number of claims on the front of packages has been increasing over the past ten years as interest in organic, natural, and whole food has grown, said Kristin Kirkpatrick, MS, RD, wellness manager of nutrition services for the Cleveland Clinic’s Center for Lifestyle Medicine. Annual sales of foods that claim to be natural are over $40 billion in 2013. That puts the "natural" claim just behind fat-free/low-fat when it comes to money-making potential.

For food companies, claims like "natural" feature prominently on the front of packaging, hoping to catch the consumer’s eye, Kirkpatrick said. “They want to seduce you into not wanting to turn it around and see the label,” Kirkpatrick said, noting that nutrition panels are almost always on the back or side of packaging.

According to Smith, the prominent natural claims work. "Admittedly, the label makes me less inclined to check the ingredients," she said.

In addition to Crystal Light, here are some foods sporting a "natural" claims you should ignore:

Nature Valley Bars: CSPI is currently in the middle of litigation over the “100% natural” claim on their packaging. The bars contain high fructose corn syrup and maltodextrin. Gardner added that he also thinks the “Nature Valley” name is disingenuous, but won’t fight it in court. A Nature Valley representative said the company doesn’t discuss pending legislation.

CSPI is currently in the middle of litigation over the “100% natural” claim on their packaging. The bars contain high fructose corn syrup and maltodextrin. Gardner added that he also thinks the “Nature Valley” name is disingenuous, but won’t fight it in court. A Nature Valley representative said the company doesn’t discuss pending legislation. IZZE Soda: In 2013, CSPI convinced Pepsi to take “all-natural” off the fruity soda product. However, IZZE still describes the product as “Sparkling Juice, and all-natural blend of pure fruit juice and sparkling water.”

In 2013, CSPI convinced Pepsi to take “all-natural” off the fruity soda product. However, IZZE still describes the product as “Sparkling Juice, and all-natural blend of pure fruit juice and sparkling water.” Trader Joe’s “All Natural”: The law firm Shook, Hardy & Bacon is currently pursuing a case against a number of Trader Joe’s products — including cookies, biscuits, cheese, apple juice and fruit jellies — that carry an “all natural” stamp, but contain synthetic ingredients such as xanthan gum, sodium citrate, ascorbic acid and potassium carbonate. Trader Joe’s has agreed to settle, but the final approval isn’t until July 2014.

The law firm Shook, Hardy & Bacon is currently pursuing a case against a number of Trader Joe’s products — including cookies, biscuits, cheese, apple juice and fruit jellies — that carry an “all natural” stamp, but contain synthetic ingredients such as xanthan gum, sodium citrate, ascorbic acid and potassium carbonate. Trader Joe’s has agreed to settle, but the final approval isn’t until July 2014. Buitoni Pastas and Sauces: These Nestle products use the “all natural” label, but contain synthetic ingredients like xanthum gum, soy lecithin, and disodium phosphate. A consumer brought a lawsuit against the company in 2013, but a California judge dismissed it on the grounds that there is no definition for “all natural,” basically proving our point that it’s a worthless moniker.

These Nestle products use the “all natural” label, but contain synthetic ingredients like xanthum gum, soy lecithin, and disodium phosphate. A consumer brought a lawsuit against the company in 2013, but a California judge dismissed it on the grounds that there is no definition for “all natural,” basically proving our point that it’s a worthless moniker. Kix Cereal: Kix boxes brag that the product is “made with All Natural Corn,” but thefederal court of New Jersey is currently hearing a case over whether this is a legitimate claim, since the corn is actually genetically modified.

Kix boxes brag that the product is “made with All Natural Corn,” but thefederal court of New Jersey is currently hearing a case over whether this is a legitimate claim, since the corn is actually genetically modified. Kashi: Parent company Kashi is still facing litigation from CSPI over “natural” claims they’ve made on Kashi products, some of which CSPI argues actually contain more artificial ingredients than natural ones. Many Kashi products no longer sport the “natural” claims, but several are still described as being made with “natural” ingredients. For example, Kashi Chocolate Almond Butter cookies contain “natural ingredients for a home-baked taste you can feel good about indulging in.”

In order to not fall into the trap, if you’re looking for natural products, Gardner and Kirkpatrick suggest bypassing labels and going straight to ingredient lists. Look for ingredients that you recognize, and be suspicious of anything you don’t. Remember, the front of the package is trying to sell you, but the back will give you the facts.

Gardner said he hopes the FDA adopts a clear definition of natural and starts enforcing the labeling itself, but until then, give "natural" claims the attention they deserve: none.