A public-relations firm backed by meat producers has unleashed a savage marketing campaign that claims plant-based meat alternatives are unhealthy, "ultra-processed imitations" similar to dog food.

The campaign rolled out in recent weeks from the industry-funded firm Center for Consumer Freedom, according to The New York Times. So far, it has included full-page ads and opinion pieces in mainstream newspapers, including The New York Times, USA Today, and The Wall Street Journal. All the marketing material raises health concerns about trendy meat alternatives, such as the Impossible Burger and Beyond Burger.

One ad posed the question "What's hiding in your plant-based meat?" Another directed readers to take the quiz "Veggie Burger or Dog Food?"

In an op-ed, the managing director of the Center for Consumer Freedom, Will Coggin, labeled meat alternatives as "ultra-processed" foods and noted that a recent study led by the researchers at the National Institutes of Health linked ultra-processed foods to weight gain.

Something to chew on

The negative marketing campaign comes amid soaring popularity of meat alternatives, which threaten to slice into the meat market's sales and profits. In recent months, big players in the meat industry had tried a different—some might say hypocritical—tactic to compete with the new comers—that is, they released their own lines of meat alternatives . Now, the industry wants consumers to think such alternatives are unhealthy.

Whether meat alternatives really are healthier than meat is a complicated question that likely depends on how you eat them, according to a Harvard nutrition researcher who spoke to the Times. It may depend on what meats you're replacing, how often you eat them, and what you eat them with. Researchers are now working on metabolic studies comparing eating beef burgers to alternatives to try to get at the question.

In the meantime, there have been studies on "ultra-processed" foods—and they have found problems, as Coggin mentioned in the op-ed. In fact, several studies in recent years have found associations between ultra-processed foods and obesity, as well as metabolic syndromes and other health problems.

That said, researchers do not fully understand that link. It's unclear if factors like nutritional content, palatability, lifestyle factors, or some combination of those can explain why ultra-processed foods often correlate with poor health outcomes.

Moreover, there is no universal definition of what "ultra-processed" foods are. A common classification system used by researchers called NOVA defines them as "multi-ingredient industrial formulations and include sugar sweetened beverages (SSBs), packaged breads, cookies, savory snacks, candy, ice cream, breakfast cereal, and pre-prepared frozen meals." But the definition has been revised and refined over recent years, muddling research on the foods.

It's worth noting that plant-based meat alternatives were not included in the ultra-processed diet that researchers gave to study participants in the NIH-led study—a morsel Coggin did not mention in his op-ed.

For now, the big players in the alternative-meat world seem unfazed by the biting marketing campaign. Pat Brown, CEO of Impossible Foods, told the Times it wasn't the company's goal to convince consumers that Impossible Burgers are the healthiest food out there, just that they're "better for you and better for the planet" than a "cow burger."

He also said that the negative campaign from the meat industry was a sign of their success. "It's hard to imagine a stronger endorsement," he said.