March 26, 2026

Ultra-Processed Foods: The Study That Changed Everything (And What It Missed) | Ep 26

Show Notes
Transcript

The average American gets over 55% of their calories from ultra-processed foods… and for years, many have suspected this plays a major role in weight gain and metabolic dysfunction.

But here’s the shocking part…

The first randomized controlled trial to actually test this didn’t happen until 2019.

Led by top NIH researcher Kevin Hall, the study compared ultra-processed vs. unprocessed diets—matched for calories, protein, fat, sugar, and fiber.

Same macros. Same calories.

And yet…

Participants gained weight on the ultra-processed diet
…and lost weight on the unprocessed diet

So what’s really going on?

In this episode, we break down:

What the study actually proves (and what it doesn’t)
Why participants eating ultra-processed foods consumed ~500 more calories per day
The overlooked role of hunger hormones like ghrelin and PYY
Why this study doesn’t fully settle the “calories in vs. calories out” debate
And the one insight almost no one is talking about

We also explore the real-world implications—cost, convenience, and why ultra-processed foods dominate modern diets.

If you care about fat loss, metabolic health, or the future of nutrition science… this is a conversation you don’t want to miss.

#UltraProcessedFoods #MetabolicHealth #WeightLoss

WEBVTT

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The average American consumes fifty five percent of their total calories in the form of ultraprocessed foods.

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Ultraprocessed foods have long been suspected of being at least somewhat responsible for the rise in obesity and metabolic dysfunction in the United States and much of the developed world.

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Incredibly, the first randomized controlled study to examine the question do ultraprocessed foods cause weight gain?

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It occurred in 2019, just a few short years ago.

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And the study concluded, perhaps not surprisingly, that ultraprocessed foods, when compared to unprocessed foods, do lead to weight gain.

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In what is generally considered the most important study on the subject, performed by the top U.S.

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government nutrition scientist at the time, a gold standard study, a randomized controlled study, researchers randomly assigned participants into two groups.

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They fed one group a diet consisting of ultra-processed foods, and the other a diet consisting of unprocessed foods.

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Now, before you guess what happened, let me add an important detail.

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Each diet, both the ultra-processed and the unprocessed, were designed with the same calories, same protein, sugar, fat, fiber, and other important micro and macronutrients.

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Still, at the end of the time on the ultra-processed diet, participants had gained about two pounds from their baseline body weight.

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Those on the unprocessed diet, they've lost about two pounds.

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Now, as a skeptic of ultra-processed foods, as someone who is a big believer in the power of whole foods, of real foods, you might assume that I'd view this study as a slam dunk, a home run, irrefutable proof that science is finally coming around to something that many of us have concluded a long time ago.

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But that's not the case.

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Because there are some important limitations with this study that make certain associations a bit weak.

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Limitations I find a bit puzzling.

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And perhaps more importantly, one of the most important insights that I think we actually can take away from this study that I've never heard anyone talk about.

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But we're going to talk about all of this today.

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With that, I'd like to welcome you to another episode of Unconditional with Norby Shickle.

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It's great to be back behind the mic.

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If you've been with me before, it's great to speak with you again.

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If you're new to the show, welcome to you too.

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We've got an exciting episode, and we're going to talk ultra-processed foods.

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And we're going deep here.

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Okay, we're getting into maybe the most important study ever performed on ultra-processed foods.

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And more than that, this is a conversation that hits on a few topics that we've touched on a bit before.

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But we're going to continue to chip away at this, right?

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These are questions related to the value of science with respect to human health and nutrition, unpacking the benefits of, and yes, there are many and costs associated with ultra-processed foods.

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And I guess what you could call a degree of skepticism on my part for what's often referred to as calories in, calories out, or energy balance, or the law of thermodynamics as an explanation for weight gain and metabolic dysfunction.

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Now, I am happy to admit my bias right from the start.

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Okay, this is a perspective which has been informed by my own experience.

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Okay, a lot of you already know this, but at one point in time, in my adult life, I should say, I was nearly 50 pounds heavier, okay, officially obese based on BMI.

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I was overweight, inflamed, and I was getting worse every year.

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But a few simple, powerful diet and lifestyle changes not only enabled me to lose the weight, but also to get lean, to get ripped, and to continue to feel better every year.

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I mean that literally.

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But it's also a perspective which has been shaped by reading the work of people like Dr.

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Weston A.

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Price.

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And I'll say not simply reading and listening to what other people say about his work, but actually reading his own words, Nutrition and Physical Degeneration, a book in which I believe is maybe the most important book written on human nutrition ever.

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Okay, full stop.

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You know, truly without equal.

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Price's travels and study of the incredible health of people following what he referred to as a primitive diet, what today we probably would refer to as an ancestral diet or a traditional diet.

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I might even call a whole foods, right, nutrient-dense diet.

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But that book is incredible.

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And it's also a perspective which has been shaped by simply paying attention to the world around me, including the health, longevity, and vitality of the people alive today.

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And it's hard not to notice that the modern world is struggling when it comes to health and fitness.

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We've gone through a lot of these stats before, but with 70% of the adult American population as obese or overweight, with an estimated 40% of us diagnosed with cancer at some point in our lives, 23% of us diagnosed with a mental disorder, and nearly 30 million Americans medicated for depression, all of which has occurred despite the greatest rise in technology and medicine the world has ever seen.

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It just seems blindingly apparent to me that something is off, it's something fundamental is off.

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And while I'm very grateful to be living in a world of wired science and medicine, we would be very wise to think very critically as individuals, because science changes all the time.

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And I remind you, that is a feature, okay, not a bug.

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Within my lifetime, the number of times that the consensus scientific opinion has been flipped completely on its head, it's too many to count, right?

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From the food pyramid to seed oils to our understanding of herd immunity.

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Is it possible that our very understanding of calories, what's described as the quote, energy of a food based on thermal heat generated when lit on fire, which let's just pause for a second and reflect on the fact that that is a very, very different process than how a body extracts energy from a food.

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Although it would be kind of cool if we did.

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But is it possible that our very understanding of calories as we know it may one day be accepted as incomplete?

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Maybe.

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But either way, whether you were in the calories don't count camp or in the law of thermodynamics camp, we don't need to resolve that now.

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Okay, we're going to plow ahead and we're going to discuss one of the most important studies in nutrition science ever.

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And it deals with the question of ultra-processed foods and weight gain.

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Do ultraprocessed foods lead to weight gain?

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And this study was performed by a guy named Kevin Hall.

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For those who listened to my episode on carbs versus fat, episode 24, I highly recommend checking that out if you haven't.

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But if you did listen to that episode, this name will be familiar.

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He's the lead author on another study, which has also been described as one of the most important studies on human nutrition, okay, a study which examined low carb versus low-fat diets and the effect on weight loss and fat loss.

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Now, both of these studies, the study I'm going to talk about today and the study from two weeks ago, they're both randomized controlled trials, okay, which makes them somewhat unique from the perspective of nutrition because randomized control is considered the gold standard when it comes to medicine, but there aren't that many of them in nutrition.

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Like they're very expensive to do.

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So Kevin Hull is no lightweight, okay?

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He was the leading nutrition researcher at the NIH at the time.

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So I want you to keep that in mind as we dive into the study on ultra-processed foods and whether these foods lead to weight gain.

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Now, before we get into the study, let's touch on the stakes and context in just a little bit more detail.

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Okay, I've already given you some of my own personal reasons for discussing the study and why I think it's very significant.

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But there's a much broader context here.

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The health implications of ultraprocessed foods is actually very significant.

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At the time of this recording, ultraprocessed foods make up a huge percentage of the diet of the average American and many other places in the developed world.

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A recent study from the CDC says around 55% of the total calories for Americans are coming from ultraprocessed foods.

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And setting aside what you probably suspect about the health implications for just a second, America's growing dependency on ultraprocessed foods is not without reason.

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Ultraprocessed foods have a lot of benefits.

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They're relatively cheap, they're convenient, reasonably tasty, they have a long shelf life.

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And given the current environment of rising food prices and the decline in the number of families with, say, one stay-at-home parent and time constraints that many families are under, you can see how ultraprocessed foods can serve as a much appreciated lifeline for many families.

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Before we say anything about the health implications of ultraprocessed foods, we will and should always keep that in mind, because that's not trivial.

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Think about it like this.

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If food is food, if a calorie is a calorie, if macros and micros are the only thing that matters, then ultraprocessed foods cannot be a driver of metabolic dysfunction in and of themselves.

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And therefore, any criticism of ultraprocessed foods or suggestion that limiting their inclusion in, say, school lunch or food assistance programs like SNAP will absolutely drive up costs, reduce convenience, and eat into the time of people who are very likely to feel they're already at their limit.

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As evidence for this claim, we can consider A, the fact that according to government estimates, 70% of commercially available food products in the United States are ultra-processed.

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Clearly there's a market.

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And B, we can look at the very study itself, the one we're going to talk about today, in which the cost of the unprocessed diet in the study was approximately 50% more expensive than the ultra-processed diet.

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Keep in mind, these two diets are matched for calories and macros and many other important micronutrients.

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And I believe that's just the food cost.

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Okay.

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In other words, that's not including the time or the labor costs associated with the additional prep for the unprocessed diet.

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I believe they actually hired professional chefs to prepare the unprocessed meals.

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So clearly that cost was not factored in.

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So the point is that this topic is much bigger than my own personal story, and it's much bigger than my own personal bias.

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We have real-world, very tangible considerations here.

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And in light of the sharp rise in the increase of ultra-processed foods and the parallel rise in obesity and metabolic dysfunction, the implications for a study like this are very significant.

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And I'll go ahead and point out that this is not lost on the researchers.

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But in order to really appreciate the impact here, we got to start on something that very few people do when it comes to this subject.

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And that is to define what we mean by ultra-processed foods.

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So what exactly are ultra-processed foods?

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I think it's fair to say that for most people, the term ultra-processed foods is sort of a, you know, I know it when I see it kind of a definition.

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Clearly, packaged junk foods falls into the category of ultra-processed.

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But beyond that, things get a little bit fuzzy.

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But there actually is a working definition of ultra-processed foods.

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And it comes from a group of researchers in Brazil led by Carlos Montero.

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Okay, and it turns out that this definition is critical to the story that we're going to tell today.

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Now, they came up with a classification system that they call NOVA.

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This isn't an acronym, but the NOVA framework groups foods into one of four categories.

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Okay, and in order to get into this, I'm going to quote from a book that I've mentioned before.

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I like this book a whole bunch.

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It's called Ultra Processed People, written by Dr.

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Chris Vantoliken.

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I think I'm pronouncing that correctly.

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Okay, highly worth the read, highly worth the purchase.

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As I always say, grab a copy, grab two copies, give one away.

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And he's got some great insights on this study, on Kevin Hall's work in general, right?

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Actually both studies, but on this study in particular, and on the Nova framework and much, much more.

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Okay.

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So let's hear from Van Tollikan describing the Nova framework directly.

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He says, quote, the first is unprocessed or minimally processed foods, foods found in nature, like meat, fruit, vegetables, but also things like flour and pasta.

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Group two is processed culinary ingredients, including oil, lard, butter, sugar, salt, vinegar, honey, starches, and traditional foods that might well be prepared using industrial technologies.

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Group three is processed food, ready-made mixtures of groups one and two, mainly processed for preservation.

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Think of tins of beans, salted nuts, smoked meats, canned fish, chunks of fruit and syrup, and proper freshly made bread.

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End quote.

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Okay, so these are the first three.

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I think they're fairly straightforward.

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We could maybe have some minor arguments about which should belong in which group.

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I imagine that many of us might not think of a can of tuna as a processed food, but as a working definition, this is a good start.

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Okay, category four is when we get into ultra processed, and this is where much more explanation is required.

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Ventolikan says, quote, and then we come to group four, ultra processed foods.

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It's long, perhaps the longest definition I've ever read of a scientific category.

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Quote, formulations of ingredients, mostly of exclusive industrial use, made by a series of industrial processes requiring sophisticated equipment and technology.

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Okay, that's confusing, but not all.

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Processes used to make ultraprocessed foods include fractioning of whole foods into substances, chemical modifications of these substances, processes and ingredients used to manufacture ultraprocessed foods are designed to create highly profitable, low cost ingredients, long shelf life, emphatic branding, convenient as and ready to consume, hyperpalatable products liable to displace freshly prepared dishes and meals made from all other Nova food groups.

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End quote.

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Okay, that is a lot.

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When we get into the realm of ultra-processed refractioning foods, we're adding chemicals, we're substituting ingredients as a means of managing costs as opposed to improving the nutritional profile of the food.

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And we're really using technology to create something that is unlike anything found in nature.

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Now, admittedly, there's a lot to that definition here.

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But if you're looking for the punchline from the team of Brazil, we get it directly from Fernanda Rauber, where she says, quote, it's not food.

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It's an industrially produced, edible substance.

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End quote.

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Tell us how you really feel.

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But this is where things get even more interesting.

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At least to me they do.

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And you won't find this in this study directly.

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But again, check out Van Tulligan's book and you'll get a lot of the history here.

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But Kevin Hall, and keep in mind, this is our top government nutrition scientist here at the time.

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He designed and orchestrated this study because when he first heard about this definition of ultra-processed foods, right, this Nova framework, and it was making some waves in Brazil.

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But when he first heard about it, he thought it didn't make any sense that a calorie is a calorie, right?

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Law of thermodynamics.

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So the author of this study assumed that this study would show that when you normalize for calories, specific macros and a few micros, and I'm paraphrasing here, but you would see the same results whether following an ultra-processed diet or an unprocessed diet.

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Let's pause there for a second.

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This study, the gold standard funded by our tax dollars, top guy in the field, was not to explore the potential damage of ultraprocessed foods.

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It was to debunk the claim that ultraprocessed foods were causing weight gain.

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To me, this is hugely important.

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And keep in mind, if you caught the episode two weeks ago, this is the same guy who supposedly debunked the carbohydrate model of insulin resistance.

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Again, with a randomized control trial, one of the very few that we have.

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Very expensive, funded with taxpayer dollars.

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I find this significant because one of the key arguments in favor of ultra processed foods is that even if they lead to weight gain, it's not because the foods in and of themselves are problematic.

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It's because we overconsume them.

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In other words, we could still eat them, but we need to just eat the same number of calories we would if we were eating whole unprocessed foods.

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If we had a little bit more willpower, you know the story.

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Eat less and move more.

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The same thing that we've heard for the last fifty years as waistlines have continued to expand, as our metabolic health has continued to suffer.

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And as we'll discuss, although this story does conclude, perhaps unexpectedly, that ultra-processed foods lead to weight gain, the study design makes it impossible to challenge the calories in, calories out model of weight gain.

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And unfortunately, I've seen this misrepresented a lot when people discuss this study, including by people whose work I really like.

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Because although the meals and snacks were designed to be matched for calories, protein, sugar, fat, fiber, and other micronutrients, they were only matched in presented calories, not in consumed calories.

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This is a significant difference.

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The participants in each group, whether they were on the unprocessed diet or the ultraprocessed diet, they were free to eat as much or as little as they wanted.

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And when it was all said and done, it is true that participants gained weight while on the ultraprocessed diet, and they actually lost weight on the unprocessed diet.

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However, the researchers calculated that those on the ultraprocessed diet consumed an average of around 500 additional calories per day than those on the unprocessed diet.

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Again, calories in, calories out.

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So we cannot really know what would have happened if the consumed calories had been the same.

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Not from this study.

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And again, this is maybe the most important study on the subject ever.

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And if you're thinking, well, maybe there's a good reason for this, you know, maybe it would be unethical, say, to limit calories for some reason.

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Well, no, not an issue.

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In fact, that's exactly what was done in the low fat versus low carb study that we discussed two weeks ago, also by Kevin Hall.

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So it can be done.

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Why wasn't it done in this case?

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I don't know.

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But given the skepticism towards ultra-processed foods as the cause of weight gain in the first place, given the history of debunking via randomized control trial, I'll say this it has my spidey sense tingling.

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But I could be wrong.

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Obviously, I'm biased, but it is something to think about.

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So let's discuss the study and feel free to come to your own conclusions, right?

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Of course, while I may have ways I would have preferred to see the study done, I am still incredibly grateful to Kevin Hall and his team for having done it.

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I'd like to see more like it.

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Okay, so the study involved 20 people, 10 men, 10 women, randomly split into two groups.

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And like with the fat versus carb study, this is a randomized controlled study, right?

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So no epidemiology, no self-reporting, strict control over what's being eaten in movement, body weight taken, body fat calculated with DEXA scans, and more.

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Okay, the total study is four weeks.

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And again, in a format which will be familiar to those who listened to my episode two weeks ago, half of the people, 10, were initially put on the ultra processed diet, which consisted of three meals a day plus snacks.

00:21:47.440 --> 00:21:55.839
The other half, also 10, were put on an unprocessed diet, which also consisted of three meals a day, plus snacks.

00:21:57.039 --> 00:21:59.440
And this initial phase lasted two weeks.

00:22:00.000 --> 00:22:02.640
And then after two weeks, the groups were flipped.

00:22:02.880 --> 00:22:09.200
Those on the ultra-processed diets were moved to an unprocessed diet, and vice versa.

00:22:09.440 --> 00:22:18.799
So while the total study was four weeks, the time on each diet was only two weeks, okay, with no washout period before or after either diet.

00:22:18.960 --> 00:22:22.400
And I said it in our discussion on the last study, but I'll say it again.

00:22:22.640 --> 00:22:23.680
I really don't like this.

00:22:23.839 --> 00:22:25.119
Okay, I'm not a researcher.

00:22:25.279 --> 00:22:25.759
I get it.

00:22:25.839 --> 00:22:30.400
I'm just a fitness nerd Monday morning quarterbacking, what I guess is standard.

00:22:30.640 --> 00:22:41.039
But as a guy who's been into health and fitness for my whole life, two weeks to assess changes to a diet, I mean, unless it's really extreme, it's just nothing.

00:22:41.279 --> 00:22:54.640
Okay, I know these trials are expensive, resources are scarce and all that, but I would have much preferred to see one group just go the full four weeks on the ultra-processed diet and the other group to go the full four weeks on the unprocessed diet.

00:22:54.960 --> 00:22:58.240
I think we would have just seen much, much clearer results.

00:22:58.880 --> 00:23:06.640
Still, when it's all said and done, the study found that while on the ultra-processed diet, participants gained about two pounds.

00:23:06.960 --> 00:23:09.759
And while on the unprocessed diet, they actually lost weight.

00:23:09.839 --> 00:23:16.319
Okay, they lost about 0.9 kilograms, so an equal amount of weight, also about two pounds.

00:23:16.960 --> 00:23:21.839
Okay, so that's about two pounds of weight gain in two weeks for the ultra-processed diet.

00:23:22.000 --> 00:23:29.519
But that's actually about a four-pound swing when you consider that the unprocessed diet actually lost about two pounds.

00:23:30.720 --> 00:23:32.480
Okay, so that's not nothing.

00:23:32.720 --> 00:23:42.240
But two pounds in two weeks, as anyone who's dieted, which I'm assuming is most of us, that's not a massive amount of weight in the grand scheme of things.

00:23:42.480 --> 00:23:48.480
Over two weeks, sure, but at two pounds, the numbers on the scale really aren't that reliable.

00:23:48.720 --> 00:23:54.000
We might be talking about changes in water retention due to sodium intake as an example.

00:23:54.400 --> 00:23:59.759
What we'd really like to know is how much fat is being gained or lost.

00:24:00.720 --> 00:24:05.440
And in addition to body weight, the researchers measured body fat using a DEXA scan.

00:24:05.920 --> 00:24:15.680
And unlike the carb versus fat study that we talked about two weeks ago, which again, a dietary intervention that was only six days, so the DEXA scan didn't show much.

00:24:15.920 --> 00:24:33.519
In this case, the DEXA scan showed a gain of about 0.4 kilograms of fat, so about a pound of fat in the ultraprocessed group, and a loss of about 0.3 kilograms, or about three-quarters of a pound, in the unprocessed group over the span of two weeks.

00:24:35.359 --> 00:24:40.960
Now, a DEXA scan is considered the gold standard for measurement of changes in fat mass.

00:24:41.440 --> 00:24:46.559
And here, I think they're probably at least directionally correct, these are pretty small changes, right?

00:24:46.720 --> 00:24:56.720
Especially at these low levels, a DEXA scan is very susceptible to say differences in fluid retention, something that the researchers do acknowledge.

00:24:56.960 --> 00:25:07.920
They say, quote, the relative large fat-free mass changes may be due to extracellular fluid shifts associated with differences in sodium intake between the diets.

00:25:08.720 --> 00:25:19.920
Indeed, individual differences in sodium intake between the diets were significantly correlated with changes in fat-free mass and body weight.

00:25:20.079 --> 00:25:26.240
Such fluid shifts may also affect the accuracy and precision of the measured body fat changes.

00:25:26.480 --> 00:25:27.519
End quote.

00:25:27.920 --> 00:25:40.240
Okay, now what they're saying, it's a bit buried here, is that changes in both fat mass and body weight were significantly correlated with individual differences in sodium intake.

00:25:40.400 --> 00:25:57.680
Okay, I take that to mean, and I'm happy to correct this if I'm misinterpreting here, is that individuals within the study eating different levels of sodium saw significant differences in the numbers on the scale and the numbers showing in the DEXA scan.

00:25:59.119 --> 00:26:11.680
Again, something which a longer intervention period, say the full four weeks, rather than flipping the groups and controlling for what was actually consumed as opposed to what was presented, could have solved for.

00:26:12.640 --> 00:26:19.279
So how much of what we're seeing is true weight loss, true fat loss versus differences in water weight?

00:26:19.519 --> 00:26:22.079
I'm not sure that anyone can say with precision.

00:26:22.400 --> 00:26:24.640
Okay, so that's the study in a nutshell.

00:26:24.799 --> 00:26:35.839
And of course, I've been giving you some of my thoughts as we've been moving through it on the design and on the results, but I want to add a few more, okay, some very important points for your consideration.

00:26:36.640 --> 00:26:40.160
We've discussed the limitations with respect to duration.

00:26:40.319 --> 00:26:55.200
We've discussed what I believe was a missed opportunity with respect to matching the diets in terms of calories, macros, micros, and presented versus consumed, as was done with the low carb versus low fat diet by the same guy.

00:26:55.440 --> 00:26:58.240
And I want to explain why I think this is such a miss.

00:26:59.839 --> 00:27:13.599
On the one hand, as someone with a strong bias in favor of whole foods and concerned about the negative health effects of ultra-processed foods, the overall conclusions from the study, they would seem to strengthen my position.

00:27:14.079 --> 00:27:35.839
But one of my biggest issues with this study is that the limitations I've described in both the design and duration of the study, they leave the door wide open for a wide range of alternate, and I believe very reasonable, disparate conclusions, quite easily supporting and reinforcing whatever bias a person had before reading the study.

00:27:37.200 --> 00:27:47.920
For people like me, skeptical of ultraprocessed foods, we can point to this study and say, see, ultraprocessed foods cause weight gain and fat gain.

00:27:48.640 --> 00:28:01.039
For people who argue that food is food, it's only the macros and the nutrients that matter, they can point to the increased consumption of calories and say, well, sure, but only if you eat them in a calorie surplus.

00:28:01.200 --> 00:28:02.720
Otherwise they're fine.

00:28:03.039 --> 00:28:22.880
People who are skeptical of food choices in general as a driver of metabolic dysfunction, maybe say opting for a genetic explanation, they can point to the short duration of the intervention, the association between salt intake and weight gain observed in the study, and reasonably argue that not much was actually established here.

00:28:23.039 --> 00:28:25.279
And from my perspective, they'd have a point.

00:28:26.319 --> 00:28:32.480
No study is perfect, and again, I very much get that I'm Monday morning quarterbacking this entire thing.

00:28:32.640 --> 00:28:39.680
But it just feels like a few minor changes would have really improved the clarity of the conclusions.

00:28:40.240 --> 00:28:41.599
Just my two cents.

00:28:42.240 --> 00:28:47.519
But even with that, there are a few bits of gold here, okay, and they're a bit buried.

00:28:47.680 --> 00:28:52.160
So you could easily overlook them if you're just focused on the conclusions of the study.

00:28:52.960 --> 00:29:05.279
Now, even as I've described the lack of control over calories consumed as a limitation of the study, the fact that calorie and macro consumption was not controlled does lead us to some interesting questions.

00:29:06.240 --> 00:29:10.880
Why did those consuming ultra processed foods consume more calories?

00:29:11.279 --> 00:29:13.519
And it wasn't just a few more calories.

00:29:13.680 --> 00:29:17.519
It's around 500 calories additional per day.

00:29:18.079 --> 00:29:19.359
Why would that be?

00:29:20.240 --> 00:29:22.960
Was the ultraprocessed food particularly tempting?

00:29:23.200 --> 00:29:31.119
You know, maybe the researchers sort of put their finger on the scale inadvertently by presenting very tasty options to the ultra-processed group?

00:29:31.519 --> 00:29:36.880
But you know, something like chicken, rice, and broccoli like three times a day for the unprocessed group?

00:29:38.000 --> 00:29:39.920
No, not the case.

00:29:40.160 --> 00:29:49.200
And again, I'm going to direct you to Van Tollikan's book here, where he points out that if anything, the unprocessed foods appear to be much tastier.

00:29:49.440 --> 00:29:53.599
We're talking prepared by professional chefs, beautifully presented.

00:29:53.759 --> 00:29:55.119
And he's not wrong about this.

00:29:55.200 --> 00:29:56.960
Okay, you can check it out yourself.

00:29:57.119 --> 00:30:01.519
You go to the actual study and look at the extended version online.

00:30:01.920 --> 00:30:06.720
And you can see pictures of the meals that were in each of the diets.

00:30:06.960 --> 00:30:09.279
And the difference is really incredible.

00:30:09.519 --> 00:30:16.799
The unprocessed diets are A, massive from a volume perspective compared to the ultra-processed, which is very telling.

00:30:16.960 --> 00:30:19.759
And B, they just look way, way better.

00:30:19.920 --> 00:30:22.400
Okay, I don't think I'm way out on a limb here.

00:30:22.480 --> 00:30:24.079
I mean, go check it out for yourself.

00:30:24.319 --> 00:30:30.240
And words don't really do it justice here, but let's take a look at one meal during the study which illustrates the point.

00:30:30.480 --> 00:30:33.680
Okay, let's look at lunch on day five.

00:30:33.839 --> 00:30:37.839
And you know, you tell me what sounds better, even without seeing the picture.

00:30:38.079 --> 00:30:41.440
So this is the ultra process menu, lunch.

00:30:41.680 --> 00:30:45.519
Spam sandwich with American cheese on white bread.

00:30:46.160 --> 00:30:48.880
Potato chips, diet lemonade.

00:30:49.039 --> 00:30:51.599
Okay, that's lunch for the ultra-processed groups.

00:30:51.759 --> 00:30:53.279
Now let's see how this compares.

00:30:53.440 --> 00:30:58.799
And keep in mind, these are the same calories, same macros, lots of the same micros.

00:30:59.200 --> 00:31:09.920
But let's see how lunch on day five, spam sandwich potato chips, diet lemonade, compares to what the unprocessed group ate on day five.

00:31:10.079 --> 00:31:30.480
Grilled beef tender roast, barley with olive oil and garlic, steamed broccoli, side salad with green leaf lettuce, tomatoes, cucumber, baby carrots, vinaigrette, apple cider vinegar, and olive oil, salt and pepper, and what looks like an entire apple cut up into slices with squeezed lemon juice.

00:31:31.119 --> 00:31:36.640
Okay, now you compare the two photos, and as I said, a couple things stand out.

00:31:36.880 --> 00:31:47.119
First of all, unless you just love spam, I am very confident that most people are going to pick the unprocessed menu if given a choice.

00:31:47.440 --> 00:31:54.079
But the other thing is you just look at from a volume perspective, and we're just talking about a massive, massive difference, right?

00:31:54.160 --> 00:32:01.359
It would be interesting if they had maybe weighed the food as like a just rough proxy or given us some sort of volume metric.

00:32:01.599 --> 00:32:31.039
But you know, with the ultra-processed option, the spam sandwich, we're talking literally about a single spam sandwich on white bread cut into quarters and of like a small bowl of chips versus the unprocessed menu, which is an entire bowl of salad, an entire bowl of broccoli, like a whole apple cut up, what looks to be about, I don't know, maybe, maybe like a fist-sized portion, I should say, of barley, plus grilled beef, right?

00:32:31.200 --> 00:32:33.599
I mean, not a tiny amount of grilled beef.

00:32:33.759 --> 00:32:36.160
This is quite a bit of food for most people.

00:32:36.720 --> 00:32:47.279
And so to me, I look at these two menus, I look at these photos, and I think, no, it's quite obvious that if anything, they were putting their finger on the scale the other way, right?

00:32:47.440 --> 00:33:01.440
When we consider Hall's admitted bias from the start, that a calorie is a calorie, it doesn't matter whether it's coming from ultra-processed or unprocessed, and the fact that the calories consumed were not controlled.

00:33:01.759 --> 00:33:10.640
Like I said, it makes you wonder if maybe even on a subconscious level, there was an assumption that the unprocessed group would consume more of the better food.

00:33:10.880 --> 00:33:15.359
I could be way off here, but I don't think that it's unreasonable to wonder.

00:33:16.240 --> 00:33:26.000
Which makes the question as to why the ultraprocessed group consumed more calories, especially given that the presented food didn't look particularly good.

00:33:26.240 --> 00:33:28.319
I mean, spam sandwiches, right?

00:33:28.640 --> 00:33:35.359
And here's what I believe to be possibly the most significant line of the entire paper, and you will blink if you miss it.

00:33:36.000 --> 00:33:49.279
The paper reads Interestingly, appetite suppressing hormone PYY increased during the unprocessed diet as compared with both the ultra-processed diet and the baseline.

00:33:49.920 --> 00:33:57.200
Also, the hunger hormone ghrelin was decreased during the unprocessed diet compared to the baseline.

00:33:58.000 --> 00:34:01.119
In other words, it's not just willpower.

00:34:01.440 --> 00:34:03.680
It's not just because you lack self-control.

00:34:04.079 --> 00:34:14.239
It's because calorie for calorie, ultra processed diets do not trigger satiety the way that unprocessed diets do, the way that real foods do.

00:34:14.559 --> 00:34:28.719
And let's connect this back to what we know about GLP1 agonists in our episode on Ozempic and the explanation as to why they work, because they crush down the hormones of hunger and they trigger satiety.

00:34:29.039 --> 00:34:35.440
Defenders of GLP1 agonists argue that they quote restore the natural signaling of satiety.

00:34:35.920 --> 00:34:39.840
Well, even if that's true, what broke the signaling to begin with?

00:34:40.159 --> 00:34:43.519
Might ultra processed foods have something to do with it?

00:34:44.159 --> 00:34:46.079
In light of what we're seeing here?

00:34:46.480 --> 00:34:48.159
Yeah, I think so.

00:34:49.440 --> 00:34:53.199
Now, why don't ultra-processed foods signal satiety in the same way?

00:34:53.519 --> 00:34:55.039
Is it a lack of fiber?

00:34:55.519 --> 00:34:56.559
Something else?

00:34:56.880 --> 00:34:59.280
Probably a topic for a future episode.

00:34:59.519 --> 00:35:04.159
But what this study is pointing to is that clearly they do not.

00:35:04.800 --> 00:35:16.719
And of course, I'm sure there are some super nerds in the group screaming protein leverage into their speaker right now, an obvious gold star for you, that would appear to be the best explanation that the researchers have.

00:35:17.039 --> 00:35:21.760
But here again is where things just get very, very interesting.

00:35:22.400 --> 00:35:34.400
So quickly, for those unfamiliar with the protein leverage hypothesis, it's basically the idea that organisms require a certain amount of protein, I guess technically amino acids, in order to live.

00:35:34.559 --> 00:35:43.199
And while we may not consciously know what that amount is, we will continue to eat, attempting to fill our amino acid requirement until it's met.

00:35:43.440 --> 00:35:53.039
So if we eat food that is high in protein, satiety will kick in faster, the feeling of fullness will kick in faster because we meet that requirement faster.

00:35:53.280 --> 00:36:00.480
If we eat foods that are low in protein, we'll eat much more because hitting that protein requirement will take much more food.

00:36:01.519 --> 00:36:05.840
But the researchers anticipated this, and the diets were matched for protein.

00:36:06.079 --> 00:36:14.639
And not only that, if protein leverage was at play here, you'd expect that most of the additional calories would come in the form of higher protein foods.

00:36:14.800 --> 00:36:16.239
But that's not what happened.

00:36:16.480 --> 00:36:23.679
The excess calories consumed primarily came in the form of additional carbs and additional fat.

00:36:24.000 --> 00:36:40.880
The paper reads, quote, however, if protein leveraging was at work in our study, it is unclear why subjects chose to meet their protein targets via compensatory overeating of dietary carbohydrate and fat rather than selecting foods with high protein content.

00:36:41.840 --> 00:36:42.400
Hmm.

00:36:42.800 --> 00:36:43.840
Kind of makes you think.

00:36:44.079 --> 00:36:50.719
So while protein leverage may be at work here, the researchers acknowledge that it's not a perfect explanation.

00:36:51.599 --> 00:36:52.800
Now what do I think?

00:36:53.039 --> 00:36:59.599
What do I think explains the delta between the satiety of ultraprocessed foods and unprocessed foods?

00:36:59.760 --> 00:37:00.800
Is it protein?

00:37:01.039 --> 00:37:02.000
Is it fiber?

00:37:02.239 --> 00:37:05.360
Sure, I think protein and fiber, they play a role.

00:37:05.599 --> 00:37:08.960
But I think it's likely something much more fundamental.

00:37:09.280 --> 00:37:16.000
Something which is found in ultraprocessed foods, which is not found in unprocessed whole foods.

00:37:16.239 --> 00:37:18.480
And those are flavor enhancers.

00:37:18.719 --> 00:37:24.400
Now this is definitely a massive topic, okay, certainly a future topic episode.

00:37:24.719 --> 00:37:44.480
But it is estimated that there are some 10,000 grass ingredients, right, generally recognized as safe food ingredients, which are added to processed and ultra-processed foods, many of which don't need to be added to the label and are oftentimes added, I would say, many times added, in combination with one another.

00:37:46.079 --> 00:37:48.400
Are some of these added as preservatives?

00:37:48.639 --> 00:37:50.079
Sure, absolutely.

00:37:50.320 --> 00:37:55.599
But a good chunk of them are added to do exactly what we're seeing here.

00:37:55.920 --> 00:38:02.159
It's to encourage you to eat, and therefore buy more of whatever the particular product is.

00:38:02.400 --> 00:38:05.199
I've made reference to the book Excitotoxins by Dr.

00:38:05.280 --> 00:38:11.920
Russell Blaylock and the book Swallow This, book with an unfortunate title, by Joanna Blythman.

00:38:12.320 --> 00:38:16.239
But that is my hunch as to what's really going on here, what we're really seeing.

00:38:16.480 --> 00:38:25.360
If you just want a preview of some of my thinking, as I said, this is definitely the topic of a future episode, something that we're going to unpack in much greater detail.

00:38:26.719 --> 00:38:27.039
Okay.

00:38:28.079 --> 00:38:29.119
I think that's it.

00:38:29.280 --> 00:38:31.119
I think we're going to go ahead and wrap up for today.

00:38:31.360 --> 00:38:32.159
Said a whole bunch.

00:38:32.320 --> 00:38:34.000
Very interesting study, of course.

00:38:34.159 --> 00:38:42.000
You know, lots to be learned directly and lots that can be connected to, especially when you start considering some of the other episodes that we've covered, right?

00:38:42.239 --> 00:38:48.800
The connection between ultra-processed foods and satiety and GOP ones as just an example.

00:38:48.960 --> 00:38:50.480
So I think there's really a lot here.

00:38:50.639 --> 00:38:52.639
I really enjoyed it, and I hope you did as well.

00:38:52.880 --> 00:39:05.840
If you are enjoying the show, if you're getting any value from it, please consider like, share, subscribe to the show, whether it's on Spotify, Apple Podcasts, wherever you enjoy listening to podcasts.

00:39:06.000 --> 00:39:07.760
Thanks again, and I'll talk to you next week.

Ultra-Processed Foods: The Study That Changed Everything (And What It Missed) | Ep 26

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