850. What if the real danger of hyperpalatable junk food isn't that it tastes too good, but that it actually silences the biological signals that tell you you're full? This episode explores groundbreaking neuroscience suggesting that overeating is driven by a lack of satisfaction rather than an excess of pleasure.
850. What if the real danger of hyperpalatable junk food isn't that it tastes too good, but that it actually silences the biological signals that tell you you're full? This episode explores groundbreaking neuroscience suggesting that overeating is driven by a lack of satisfaction rather than an excess of pleasure.
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References
The body sends a signal: Perspectives on interoception | PLOS Biology
In defense of pleasure: We need to rethink food reward and obesity | PLOS Biology
Maybe the problem with highly-processed, "hyperpalatable" foods isn't that they give us too much pleasure. Maybe it’s that they block our ability to feel satisfied. An interesting new study has me rethinking some of our favorite assumptions.
Hello there I’m Monica Reinagel and you are listening to the Nutrition Diva podcast, a show where we take a closer look at nutrition news, research, and trends to help you make sense of all the information that’s out there. I'm glad to have you with us today.
I want to talk about a neuroscience paper that crossed my radar screen this week. It’s actually a pretty technical finding, but it really has me thinking a little differently about a couple of things, like the relationship between pleasure, appetite, over-eating, and food processing. Are you ready for all that? Let’s dive in!
Hyperpalatability is a term that we throw around a lot these days. This term started gaining traction 10 or 15 years ago, first in research circles and then in the general discourse. It was meant to describe foods that seemed to override our usual satiety signals, and this compels us to overconsume them–stuff our grandmothers would have described as junk food.
Researchers eventually zeroed in on the combination of sugar, fat, and salt as being especially “addictive.” The usual story is that this combination overstimulates the reward pathways in the brain, which overwhelms our self-control, and drives us to eat more than we need. And out of this narrative, an explanation for the obesity epidemic emerged: The spectacular rise in obesity over the last 50 years was caused primarily by the increasing presence of highly processed, hyperpalatable foods in our food supply. So we got fat because there was just too much irresistible junk food lying around.
But this paper that was published in late 2025 by a couple of neuroscientists named Justin Sung and Dana Small has introduced a really interesting plot twist. The authors suggest that we don’t overeat these foods because they are so pleasurable. Actually, quite the opposite. These foods may impair the body’s ability to signal to the brain that it has received enough nutrition.
Let me back up for a second to explain the way this is supposed to work. When we eat, sensors in the gut and liver detect nutrients and energy coming in, and they send signals to the brain. Those signals help the brain determine whether that food actually delivered what the body needed. When that system is working well, eating leads not just to enjoyment but to a sense of satisfaction, as in, “Thanks, I’ve had enough.”
What Sung and Small are suggesting is that the problem with “hyperpalatable” foods isn’t that we enjoy them so much that we can’t stop eating them. Rather, it's that they are blunting the signals that normally cause us to stop eating. The brain just isn’t getting the message that the body has been fed.
And it’s also worth pointing out that ultra-processed foods don’t have a monopoly on the combination of salt, sugar and fat. Those ingredients can be—and often are—combined very effectively in home kitchens as well. So while most of the hyperpalatable foods in our environment may be ultra-processed, minimally processed foods with that same combination of ingredients would presumably have similar effects.
Now I find this fascinating because it challenges several popular narratives about pleasure, desire, body weight, food processing, and even how the new anti-obesity medications affect us. If Sung and Small are correct, overeating isn’t just about hedonism or gluttony or even hijacked reward systems. It’s about incomplete signaling (or, impaired interoception). People keep eating because the brain is still waiting for confirmation that the body has been adequately nourished.
And this helps me understand why some foods that I find very pleasurable (like high quality dark chocolate) are nonetheless easy to stop eating after a few bites. And why other foods that I actually don’t think taste all that great (such as cheap milk chocolate candy) can be weirdly compelling. Maybe it’s not that I’m chasing “more pleasure,” so much as looking for that sense of “having had enough,” and that never quite arrives.
Now perhaps the end effect is the same either way: overconsumption that leads to unhealthy weight gain. But I still think this insight forces us to rethink or reframe a lot of other assumptions and anxieties that often crop up in these conversations.
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This new understanding of how the brain registers pleasure and satisfaction in response to food also has implications for the more widespread adoption of anti-obesity medications like Wegovy.
One of the concerns that I’ve heard is that these drugs don’t just reduce hunger or food intake—they somehow rob people of their ability to enjoy food. By turning down the volume on appetite and cravings, people fear they’re taking away one of life’s great pleasures.
So a little context here: These GLP-1 medications don’t just affect how hungry people feel. Many people using these medications also report that they are less interested in foods that they once found irresistible. Specifically, they no longer crave the sweet, salty and fried stuff. From the outside, maybe that looks like a loss. But for people who have lived with persistent, intrusive and unwelcome thoughts about food (aka “food noise”), having those cravings and urges muted is often a huge relief.
But reducing desire is not the same thing as reducing pleasure. Having fewer cravings for things doesn’t necessarily mean that you can no longer enjoy those things when you choose to eat them. In fact, perhaps it’s easier to take pleasure in food and eating when it’s no longer driven by insatiable compulsion. And when it's no longer followed by shame at having eaten more than you “should have” or meant to.
So despite the fear that these medications will eliminate the ability to take pleasure in eating, which I've noticed is often expressed by people who enjoy food but do not struggle with their weight, well then perhaps these drugs are really about helping people feel more satisfied. And that may offer a kind of freedom that some people haven’t experienced in a long time–the freedom to think about something other than food for a while.
Now I want to be careful not to overstate or oversimply things. It may be that these interoceptive feedback pathways are already impaired in people who are predisposed to weight gain. After all, some people who are exposed to the same food environment do not become obese. And it’s not because they just have more self-control!
This research also doesn’t address whether GLP-1 medications affect this specific interoceptive pathway or whether they’re changing eating behavior through other mechanisms that just happen to overlap with it.
But it’s an interesting overlap, isn’t it? Sung and Small are challenging the idea that overeating is driven by foods that deliver “too much pleasure.” At the same time, we have a class of medications that not only reduces overeating but also seems to reduce the desire for those so called “hyperpalatable” foods. What I take from all of this is that “desire” and “pleasure” are not the same thing.
Now there’s one other related point I want to explore. Food processing can obviously be used to produce “hyperpalatable” foods at scale, making them cheap, convenient and ubiquitous. And this certainly does appear to have contributed to the rise in obesity. Even if maybe we had the mechanism slightly wrong. So it’s not surprising to me that a lot of food policy and nutrition experts have been calling for the regulation or maybe even the abolition of ultra-processed foods.
Interestingly though, people who are taking GLP-1s consistently report that their desire for certain processed foods drops dramatically. In particular, those foods that once felt so irresistible—the ones that are high in sugar, fat and salt—are just not as compelling. As more and more people have begun using these medications, it’s starting to have a real impact on commerce. We’re seeing significant declines in sales of fast food and packaged snacks.
At the same time though, when you have a smaller appetite, it does becomes more of a challenge to get enough nutrition before you get too full. And sales of processed foods that have been formulated to deliver more protein, fiber, and other nutrients for fewer calories are ticking up noticeably.
And this is where things get interesting, because the much-maligned category of “ultra-processed foods” that a lot of people would like to ban, it includes both types of foods. It includes those “hyperpalatable” snack foods that may promote overeating. But it also includes foods that help people meet their nutrition needs when their appetite is low. So the advice to “avoid ultra-processed foods” is a little too general to be useful.
Rather than asking, “Is this food too processed?” a more useful question might be, “Is this food helping me to meet my nutritional needs or goals?” Sometimes those foods are minimally processed. Sometimes they are ultra-processed.
The research that I started the episode with reinforces the point that food processing, per se, is not the real villain. And neither, for that matter, is pleasure. Our appetite appears to depend on signals that can be weakened or distorted either by our biology or perhaps by our dietary patterns. So for me, that's a helpful reminder to avoid oversimplifying the narratives around appetite, reward, enjoyment, and also the narrative about how the foods we eat and crave are made.
So this is usually the point in the episode where I’d wrap things up with a few practical takeaways. But that wasn’t really my goal today. I wanted to share some science that I found really interesting and that casts some familiar notions about appetite, palatability, food processing, and even these new medications in a slightly different light.
So this week, I’m going to let you write the takeaways. What stood out to you? What questions did this raise? Has anything that I have shared with you change anything about how you think about food processing? Or about weight loss medications? If you’d like to share your thoughts, you can email me at nutrition@quickanddirtytips.com. And as always, you can also send along any questions you’d like me to tackle in a future episode.
Nutrition Diva is a Quick and Dirty Tips podcast. Holly Hutchings is our Director of Podcasts. Steve Riekeberg is our audio engineer. Morgan Christianson heads up Podcast Operations & Advertising. Rebekah Sebastian is our Manager of Marketing and Publicity. Nat Hoopes is our Marketing and Operations Assistant. And Maram Elnagheeb is our Podcast Associate. Thanks to all of them but most of all thanks to you for listening!