Katya Still Life

Told Ya So: It’s the Ultra-Processed Food

Kevin Hall is a bit of a myth buster. In a number of studies, he has put popular ideas about obesity and nutrition under the microscope of objective data. And by doing so, he proved them wrong. But in a new study published yesterday, he proved himself wrong about ultra-processed food.

In a carefully controlled study, he randomized people to consume either whole, unprocessed foods or ultra-processed foods. He didn’t expect to see a big difference. His results, appearing yesterday in Cell Metabolism, showed just the opposite – a big difference favoring the whole, unprocessed foods.

Years of Mere Associations

This is great news. For years, we’ve had only speculation about an association between ultra-processed food and obesity. But now we have rigorous experimental evidence to explain it in a small and very well controlled study.

Hall et al found that people receiving meals of ultra-processed foods gained significant weight in this 2-week trial. The meals of whole, unprocessed foods led to weight loss. The researchers carefully matched the meals between the two groups. Calories per serving, energy density, sugar, salt, fat, and fiber were all equivalent.

However, people ate more of the ultra-processed foods. They did this even though they rated the different meals equally pleasant and familiar. Something about the ultra-processed food seems to be driving overconsumption.


Folks who have been complaining for some time about the dangers of big food pushing ultra-processed junk food are feeling vindicated. It’s great when presumptions prove to be true. Dariush Mozaffarian was effusive in describing the study:

These are landmark findings that the processing of the foods makes a huge difference in how much a person eats.

Putting people in a controlled setting and giving them their food lets you really understand biologically what’s going on, and the differences are striking.

Barry Popkin said this presents an important challenge to the global food industry:

Let’s see if they can produce ultra-processed food that’s healthy and that won’t be so seductive and won’t make us eat so much extra. But they haven’t yet.

More Work to Do

However, Hall cautioned that we have much more to learn about ultra-processed foods. He is planning important follow-up research to understand why these foods have these effects. Simply demonizing processed foods may not bring better health outcomes. Hall reminds us:

We’re talking about foods that make up more than 50 percent of people’s diets, and they can be very attractive to people who have limited time, money, skills and access to ingredients that they can use to make meals from scratch. For people who are working two jobs just to make ends meet and have a family to feed, a frozen pizza looks very good at the end of the day.

Food is a complex and important part of our lives. The prospect of getting a better handle on objective truth about how it can affect our health is genuinely encouraging.

Click here for the study. For further perspective, click here and here.

Katya Still Life, painting by Zinaida Serebriakova / WikiArt

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May 17, 2019

3 Responses to “Told Ya So: It’s the Ultra-Processed Food”

  1. May 17, 2019 at 9:59 am, Allen Browne said:

    Yup – this is dynamite. We are getting closer to understanding the problem.

    But it’s not the food processors fault – the advantages to ultra processed foods are real in every day life to the producer and to the consumer. They just happen to be bad for health.

    Nice to see we are getting further and further from blaming the patient.

    A new chapter is beginning.


  2. May 17, 2019 at 10:25 pm, Mary-Jo Overwater said:

    I still believe that in addition to funky ingredients, there’s something about the packaging of ultra processed foods that contributes to how these items drive metabolic and appestat changes. Would like to see a study that might be able to disentangle that out.

  3. May 28, 2019 at 1:19 pm, Doina Kulick said:

    The food industry is adding countless additives to their processed foods. Most of these additives have not been studied for their long term effects on human metabolism. A recent study for example showed that calcium propionate used in baked goods to maintain freshness increases norepinephrine resulting in increased glucagon in humans.
    Most recently FDA approved the use of allulose ( a low calorie epimer of fructose) in foods at dose hundreds time more than the amount this rare monosaccharide occurs in natural foods. Again no adequate safety studies for allulose used at this high dose. A long term animal study feeding rats allulose over 18 months show increase in the size of the liver, kidney and pancreas in these animals.
    When will the food industry, USDA and the FDA stop experimenting on people?
    When will the profits of food industry become irrelevant in the face of a sicker and sicker nation?