Ultra-processed foods are undergoing increased scrutiny as Health and Human Services Secretary Robert F. Kennedy, Jr. and his supporters blame these often tasty snacks for contributing to chronic diseases in the U.S.

But what is ultra-processed food? There still isn’t a universal definition.

While many ice creams, chips and sodas are considered ultra-processed, there’s also a wide array of other foods that can be included in a healthy diet that fall into the same category, such as tofu, some canned fruits and vegetables, protein bars, cereals and nut milks.

“These are all quite processed and some of them can be classified as ultra-processed foods but because of their nutrient profiles, they might be better for us and not associated with the worst health outcomes,” said Michele Polacsek, professor of public health at the University of New England and an expert on promoting healthy food choices.

Does that mean these foods will be targeted, too? Probably not, said Marion Nestle, a nutrition expert and emeritus professor at New York University.

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“That would be impossible because of the way that Americans eat,” she said, as research shows over 70% of American calories come from ultra-processed foods.

Ultra-processed foods, or UPFs, are foods that have been made by food companies using manufactured ingredients, rather than actual foods. If you’ve ever taken a look at some food labels, you may not recognize many of the ingredients listed. These are likely ultra-processed ingredients that are used to make food “taste better, look better and last longer on the shelf,” Nestle said.

Research has shown UPFs replace healthier foods and encourage people to eat more calories, Nestle said. Ultra-processed foods have been linked to about 30 health conditions, including obesity, diabetes, heart disease, certain cancers and mental health disorders, according to a 2024 study published in the British Medical Journal.

In May, Kennedy and his “Make America Healthy Again” commission targeted ultra-processed foods in a 69-page report.

The U.S. Department of Health and Human Services announced the administration is seeking information and data to help develop an official definition for ultra-processed foods, according to a July 23 statement.

While it’s a good first step, Polacsek said not all UPFs are the same and there isn’t enough data to determine which ingredients or processes in packaged foods lead to negative health outcomes.

“We don’t have all the evidence we need,” she said. “We need a lot more research on this.”

It would be a mistake to create policy based on the data available on ultra-processed foods, Polacsek said. But if the administration makes policy decisions based on a universal definition, she hopes agencies will also allocate funding to research how it’s impacting public health and the food industry.

In the meantime, Nestle recommends minimizing the amount of ultra-processed foods you eat but also reminds consumers that some contain nutrients that can be incorporated into a healthy diet.

In a 2023 study, researchers at the U.S. Department of Agriculture led a study that showed how it was possible to build a healthy diet with 91% of the calories coming from ultra-processed foods. However, study authors noted the diet was particularly high in sodium and didn’t contain enough whole grains.

“The basic principle of healthy eating is variety,” Nestle said. “If you eat a lot of different kinds of food, and most of them are minimally processed, you’re doing fine.”

“Food is one of life’s greatest pleasures, it’s really important to enjoy what you eat.”

Adrianna Rodriguez can be reached at adrodriguez@usatoday.com.