The National Institutes of Health scientist Kevin Hall pioneered the first study to definitively prove that ultra-processed foods — like chicken tenders and prepackaged snacks — drive us to overeat and gain weight.
Yet at home, he doesn't avoid convenience foods and sometimes buys ultra-processed snacks for his kids.
Hall said his strategy is not as contradictory as it seems if you understand the nutrition science behind his choices.
What we know — and don't know — about ultra-processed foods
Six years ago, Hall was the first to definitively show that ultra-processed foods can lead people to eat more food (about 500 calories a day) and gain weight.
This was a big deal: Before that, scientists could only draw connections between ultra-processed diets and long-term health outcomes. There wasn't a definitive cause-and-effect relationship established between ultra-processed foods and poor health.
Hall's team at the NIH kept study participants in a laboratory setting, fed them a strictly prepared diet of ultra-processed or fresh foods, and analyzed what effects different diets had on their health.
Since then, research on UPFs has snowballed. Ultra-processed foods have become the poster child for everything that's wrong with American diets, with politicians on both sides of the aisle pledging to crack down on them.
Do not let perfect be the enemy of good, Hall says
Hall is not advocating that people cut out all UPFs, and he doesn't want to tell people what to eat.
"I don't stand on my soapbox to claim to know all the answers," he said.
Scientists still don't know exactly why ultra-processed foods are so bad for us. More importantly, he said that we don't know yet whether all ultra-processed foods are, by definition, bad for people.
The NOVA scale — used to differentiate between unprocessed, processed, and ultra-processed foods — only looks at how food was prepared. It does not account for nutritional value.
Is a can of ready-to-heat chili just as unhealthy as a jelly doughnut? They're both ultra-processed, but one contains meat, beans, and non-starchy veggies. The other has sugar, maybe some butter, refined flour, and lots of oil.
At home, Hall tries not to let perfect be the enemy of good. He makes educated guesses about which ultra-processed foods are better for his health while also being a realist about convenience.
Like many nutrition and longevity professionals, he prioritizes non-starchy vegetables, whole grains, fruits, legumes, and beans. He also stocks chicken nuggets in his freezer for nights when the kids need a quick dinner. Goldfish crackers are not forbidden.
He also avoids buying ultra-processed foods with a lot of added sugar, saturated fat, or sodium.
"Would it be better if you had made the homemade version of that?" Hall said. "Maybe. It's possible that there's some weird additive or some ingredient in that food that is not good for you. We don't have the science on that yet, but applying what we do know, I think you can still make educated choices."
Plastic packaging doesn't mean it's bad for you
Canned and frozen foods can be great options for busy folks trying to eat healthier. And they're not all ultra-processed.
"People kind of mistake processed and ultra-processed," Hall said.
"There is some degree of confusion. It's typically people using these rules of thumb: If it comes in a can or a box or a package and has plastic around it, it's ultra-processed. I'm sorry, they put cucumbers in plastic at my supermarket, they're not ultra-processed!"
That kind of rigid thinking leads people to fear foods like canned beans, tinned fish, or frozen vegetables, pantry staples that can make it easier to cook at home and regularly eat foods that are great for longevity.
"There's so many canned beans that are just like, seasoned," Hall said. "They don't have some weird additives associated with them. A lot of people don't realize those are just processed foods."
