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Comment by msteffen | original | Food processing influences metabolism and brain activity
[−]msteffen · 2026-10-11 Sun 04:05 UTC · link
For anyone who hasn’t read it, I highly recommend the book “Ultraprocessed People.” It's a scientifically literate and yet quite readable overview of research into ultraprocessed foods.

FWIW there are four categories:

1 is whole foods (eg fruits, nuts)

2 is stuff that is processed but still basically an ingredient (eg flour, maple syrup)

3 is combinations of 1 and 2 (most restaurants are here)

4 is ultraprocessed food (UPF): things that were not food that have been turned into food (e.g. modified starches, artificial flavors). Also, anything containing UPFs is a UPF, so e.g. most breakfast cereal (food coloring, flavors)

The basic thesis (which this research challenges, interestingly) is that UPFs aren’t inherently bad, but food scientists are shockingly good at creating highly specific and desirable flavors and textures (the book gives the example of a food company creating "ice cream" out of various modified starches and flavors so that it doesn't melt during shipping), and foods that come out of this process have generally been engineered to overwhelm our natural feedback mechanisms against overeating in order to sell more product.

[−]ImaCake · 2026-10-11 Sun 04:47 UTC · link
> is that UPFs aren’t inherently bad

My reading of Ultraprocessed People was more that the author was very careful to only pin on UPF's what could be proved to be true. The between the lines read certainly felt like "you should probably not eat UPFs".

I would humbly add that any of Michael Pollan's books, especially "In Defense of Food" are a good answer to how we should eat if we can't eat McDonald's. I have certainly found restarting the dining table tradition to have incalculable benefits for my family.

[−]djtango · 2026-10-11 Sun 11:59 UTC · link
> I have certainly found restarting the dining table tradition to have incalculable benefits for my family.

I would love to hear more of your experiences here if you would care to share? It is something I have been thinking about a lot recently (the slow erosion of this practice and its benefits that we're giving up)

[−]Lerc · 2026-10-11 Sun 05:44 UTC · link
>foods that come out of this process have generally been engineered to overwhelm our natural feedback mechanisms against overeating in order to sell more product.

That's the point at which it becomes highly speculative.

It seems to invoke an assumed knowledge of human biology that either does not exist or is known by some select few in some form of conspiracy (somewhat unlikely)

It reminds me of raw foodists that argue that cooking is bad because humans harnessed fire only after we'd mostly evolved. Or a magnet bracelet peddler claiming that since we started wearing shoes, that separation from the earth's magnetic field means we need the bracelets now.

[−]piker · 2026-10-11 Sun 06:17 UTC · link
It didn’t take an advanced understanding of reward pathways to realize that things like nicotine and cocaine were highly addictive and that aspect could be concentrated (e.g. crack).
[−]kioleanu · 2026-10-11 Sun 06:30 UTC · link
It’s not speculative if you get to have a glance behind closed doors https://archive.ph/3wUEN
[−]msteffen · 2026-10-11 Sun 07:09 UTC · link
> That's the point at which it becomes highly speculative.

The “…in order to sell more product” part is scientifically speculative, I agree—the book makes the claim, but the scientific research it references does not, IIRC. The book’s author imputes it from interviews and the like.

The “overwhelm…feedback mechanisms” part is mainly substantiated by a 2019 study by Kevin Hall where, similar to TFA, they had people essentially live inside a calorimeter and eat calorie- and nutrient-matched meals that were UPF or not. They found that when given UPF, the same people ate more and faster, and gained weight at a pace that surprised the study authors (who were initially skeptical of the theory and had constructed the study to try and disprove it. The study author is interviewed and explains why he found it compelling).

Whether you find the evidence compelling is, of course, up to you :-), but I felt the book did a good job interviewing members of the obesity research community and tracing the history of the theory.

[−]rgoulter · 2026-10-11 Sun 06:17 UTC · link
"UPF" is such a weird term to me.

For one, for achieving fat loss, it's surely simpler to focus on factors like calories & how full the food makes you. -- With that perspective, yeah it's obvious that fried chicken and sugary chocolate aren't great for your health when eaten frequently.

For another, e.g. it seems that nutritionally, something like "diet coke" is strictly better than the sugar drinks it replaces: you get the same taste, but zero calories. -- I mean, zero-calorie drink is clearly UPF but also nutritionally beneficial. I don't see "UPF" as a practical way to look at it.

[−]Maakuth · 2026-10-11 Sun 06:43 UTC · link
The soda replaced is also a UPF though, which does line up with the idea that none of them are good for you.
[−]msteffen · 2026-10-11 Sun 06:43 UTC · link
The book discusses this a bit, actually. It basically credits the UPF theory to one Brazilian researcher, Carlos Monteiro, and discusses how he developed the theory by applying epidemiological techniques to the obesity epidemic in Brazil. It gives the specific example that, in Monteiro's research, if a family bought sugar at the grocery store, it actually reduced the likelihood that they were obese because, even though sugar is not healthy, it meant they were still cooking at home.

My understanding is that he would probably make similar predictions about your examples: people who eat fried chicken and chocolate as part of a mostly home-cooked diet are less likely to be obese than people who drink diet coke as part of a diet that mostly comes out of wrappers. He would probably also say that there's nothing inherently bad about diet coke, but there is something bad about getting all your food from people trying to make money instead of from people who love you.

[−]ggm · 2026-10-11 Sun 07:07 UTC · link
I thought that aside from the social context above, there is a theory that artificial sweeteners actually cause paradoxical effects in the metabolism because of triggers associated with the sweetness not the glucose/sucrose content. Ie specifically "diet" soda aside from eating out a Lot, may not be helping.
[−]mitxela · 2026-10-11 Sun 11:31 UTC · link
What could the paradoxical effects possibly be? Storing energy takes actual energy, and can't be triggered by hormones alone.
[−]rgoulter · 2026-10-11 Sun 09:38 UTC · link
I'd say "calorie dense food that's highly palatable makes it easy to consume more calories than you expend, and that makes you fat". -- I mean, that's a mechanical model explaining how you get fat.

e.g. obviously not practical for everyone but Taub's "Twinkie Study" showed fat 27 lbs of fat loss even from a diet of decidedly calorie-dense food like twinkies and doritos. https://www.psychologytoday.com/us/blog/comfort-cravings/201...

I think that UPF mostly aligns with that in that the food that's "UPF" is generally calorie dense, highly palatable, low satiation.

But...

> He would probably also say that there's nothing inherently bad about diet coke, but there is something bad about getting all your food from people trying to make money instead of from people who love you.

At this point, it seems more a discussion of morals and social values rather than a scientific "how to lose fat".

[−]armitron · 2026-10-11 Sun 08:59 UTC · link
Zero calories doesn’t mean it’s healthy, as all those drinks are loaded with artificial sweeteners some of which have a strong insulin response and are also associated with cancer.
[−]rgoulter · 2026-10-11 Sun 09:28 UTC · link
> and are also associated with cancer.

Last time I looked into this, the strongest research showed "we looked and couldn't find any evidence it's not associated with cancer".

That is, to hear "artificial sweeteners = cancer, I'm better off with the sugary drinks" was the wrong conclusion to take.

[−]amanaplanacanal · 2026-10-11 Sun 10:20 UTC · link
I haven't seen evidence that artificial sweeteners cause a strong insulin response, but would certainly love to. Can you point me to such evidence?
[−]irthomasthomas · 2026-10-11 Sun 11:32 UTC · link
Here are a few papers:

1. Sucralose increases peak insulin response when co-ingested with carbs: "Sucralose Affects Glycemic and Hormonal Responses to an Oral Glucose Load" (Pepino et al., 2013, Diabetes Care) https://pubmed.ncbi.nlm.nih.gov/23633524/ Finding: Consuming sucralose 10 minutes prior to an oral glucose tolerance test increased peak plasma insulin levels by ~20% and decreased insulin clearance compared to water.

2. Microbiome-driven glycemic & insulin dysregulation: "Personalized microbiome-driven effects of non-nutritive sweeteners on human glucose tolerance" (Suez et al., 2022, Cell) https://pubmed.ncbi.nlm.nih.gov/35987213/ Finding: A randomized trial showing saccharin and sucralose alter gut microbiota composition, leading to personalized impairments in glucose tolerance and postprandial insulin responses.

3. Reduced insulin sensitivity from daily intake: "Sucralose decreases insulin sensitivity in healthy subjects: a randomized controlled trial" (Romo-Romo et al., 2018, AJCN) https://pubmed.ncbi.nlm.nih.gov/30535090/ Finding: 14 days of daily sucralose intake significantly decreased insulin sensitivity in healthy young adults compared to placebo.

4. Direct pancreatic beta-cell mechanism: "Sweet Taste Receptor Expressed in Pancreatic β-Cells Activates the Calcium and Cyclic AMP Signaling Systems and Stimulates Insulin Secretion" (Nakagawa et al., 2009, PLoS ONE) https://pubmed.ncbi.nlm.nih.gov/19352508/ Finding: Sweet-taste receptors (T1R2/T1R3) expressed on pancreatic beta-cells bind sweeteners (sucralose, Ace-K, saccharin), mobilizing intracellular cAMP and Ca2+ to stimulate insulin secretion.

[−]andsoitis · 2026-10-11 Sun 11:40 UTC · link
> Coke Zero

> I mean, zero-calorie drink is clearly UPF but also nutritionally beneficial.

What nutrition do zero-calorie manufactured drinks like Coke Zero provide?

[−]ShinyLeftPad · 2026-10-11 Sun 06:32 UTC · link
so what category is simple steak then
[−]ludicrousdispla · 2026-10-11 Sun 06:37 UTC · link
I would think that a simple steak is a whole food, but I have no idea what would be in a SimpleSteak™
[−]refurb · 2026-10-11 Sun 06:54 UTC · link
Most of the “chemicals” in so-called ultra-processed food aren’t added so customers overeat, they’re added to improve things like shelf-life or product quality (modified starch thickeners).

I’d find it hard to believe there are evil food scientists in big food companies who are nefariously designing food for overeating.

What is more likely is they are creating food that taste good, which shouldn’t surprise anyone. Now if the claim is they work towards this goal without much concern about things like sugar content or glycemic index, I could believe that.

But at the same time nobody thinks eating a whole bag of five servings of Doritos is a healthy food choice. If you’re designing good tasting food and assuming people will eat one serving as a part of a healthy diet, then no nefarious goals are required.

[−]Madmallard · 2026-10-11 Sun 07:35 UTC · link
Lol the entire junk food industry would like to hire you for PR

You know cigarette companies have existed for 100 years and bought food companies right? You know their stuff is blatantly toxic and kills millions of people a year and they advocated ads and stuff and paid doctors to say it's not harmful right?

Like what world do you live in?

You really think hanlon's razor or any other thing like that remotely applies here?

[−]pydry · 2026-10-11 Sun 08:25 UTC · link
>I’d find it hard to believe there are evil food scientists in big food companies who are nefariously designing food for overeating.

You really find it hard to believe that profit making companies that engineer food would engineer food for profit?

What about if they advertised it with a catchy phrase like "once you pop you can't stop"? Would you still shake your head and say "not credible"?