Why do scientists disagree so much about ultraprocessed foods? A new study suggests there may be another piece of the debate worth paying attention to: researchers' connections to the food industry.
Researchers reviewed 69 academic articles published from 2009 through 2025 that either criticized Nova, the system widely used to classify ultraprocessed foods, or discussed potential benefits of these foods. They found that 91.3% of the articles included at least one author they identified as having a food industry relationship.
That's a striking number, but it needs context. The study does not show that industry connections caused researchers to reach particular conclusions. And having a relationship with a food company or industry organization doesn't automatically make someone's scientific argument wrong.
Nova sorts foods into four groups based on how and why they're processed. Its ultraprocessed category includes many packaged snacks, candy, sweetened drinks and ready-to-eat foods. Researchers frequently use the system to study possible links between diets high in ultraprocessed foods and health.
But Nova is also debated. One concern is that foods placed in the same ultraprocessed category can be very different nutritionally. Scientists are still trying to understand how much processing itself matters and how much of the health risk seen in studies might be explained by other differences among foods and diets.
The new systematic review, published in the American Journal of Public Health, didn't try to settle that debate. Instead, the researchers looked at who was publishing criticism of Nova and arguments about possible benefits of ultraprocessed foods.
Of the 232 authors included in the review, 68.5% had some type of food industry relationship identified by the researchers.
Some relationships were disclosed in the articles, while others were found through publicly available online information. Because the full study is not publicly available, however, there are important details that are not disclosed, including exactly what types of connections researchers counted in each category and whether relationships found elsewhere would have been required to be disclosed by a particular journal.
The researchers also found that articles involving authors with industry relationships were more likely to include arguments defending or promoting potential benefits of ultraprocessed foods than articles in which they identified no industry ties.
That doesn't tell us why.
A connection to the food industry doesn't prove that a company influenced a scientist's work. It also doesn't tell us whether a criticism of Nova is scientifically sound. Instead, knowing about those relationships gives readers another piece of information to consider alongside the research itself.
“This study is not saying that criticism of Nova is illegitimate. Some of those criticisms identify real ways the system can be improved,” study author Erica LaFata, a research scientist at Oregon Research Institute, said in a news release. “But readers should know who is shaping that debate.”
The review also looked beyond individual researchers. It found that 65.2% of the articles appeared in journals associated with nutrition societies that reported partnerships with the food industry.
Again, that finding doesn't show that an industry partnership influenced what a journal published. Instead, it adds to the researchers' broader argument that financial and professional relationships should be visible when people are weighing competing claims about food and health.
The authors make a stronger argument in their conclusion. They point to the tobacco industry's documented history of using scientific debate to cast doubt on evidence about smoking and suggest the food industry “may be following a similar playbook.”
This study alone can't establish that.
It found industry relationships among many of the researchers publishing criticism of Nova, along with differences in the kinds of arguments appearing in articles with and without identified industry connections. It did not show that food companies directed those arguments or deliberately created scientific disagreement.
And disagreement does exist for reasons beyond industry involvement. Nova has limitations worth studying, just as the growing evidence connecting high consumption of ultraprocessed foods with poorer health deserves serious attention. Both can be true.
For readers, that's perhaps the most useful way to view the new findings. Funding and industry relationships can provide important context when judging nutrition research, particularly when those connections aren't obvious. But they can't tell us whether a scientific claim is true.
That still comes down to the evidence.
Funding details for the review were not available but there were not reported conflicts of interest.