> “The two meals are matched within 1 percent of carbs, fat, proteins, calories, water, and salt,” said Zach Hutelin, a researcher at the institute and the study’s first author.
Note that fiber is not part of that list. Stripping out fiber essentially means that our gut microbiome is starved. Not coincidentally, it also means that these foods are much less prone to spoilage.
> The non-UPF and UPF test meals were closely matched on meal weight, energy, energy density, macronutrients, available carbohydrate, glycaemic index and load, total dietary fibre, sodium and water (all ≤1.6% deviation between meals; Fig. 1b).
So they did match glycemic index, which the article omits.
I was about to comment that the physical structure of the food and the fiber content also make a difference. For instance, rolled oats are available in different thicknesses, and the thicker ones don’t digest as easily. Brown vs white rice is another example.
But these examples have different glycemic indexes, which the study matched for.
Not only psychology, but training. If your body gets a load of sugar every time it tastes UPF additives, it learns to release insulin on taste to protect itself.
Grandparent post is talking about the connection between taste and insulin, which would be a different mechanism from when a given food causes a spike in blood glucose based on its composition. Meaning that you'd get a different insulin response if you ingested something bypassing taste receptors vs being able to taste that food.
Another option is that it's affected by the order of consumption.
I know somebody who got really into blood glucose monitoring, and she tells me that the order in which she eats a meal affects how much it spikes her glucose. So if she eats a piece of toast followed by a piece of cheese, it causes her a bigger glucose spike than she'd get if she eats the cheese first and then the toast.
Looking at the two meals in the study: if I sat down to eat the processed one, I'd probably start with the veggie straws. If I saw down to eat the unprocessed one, I'd almost certainly start with the egg or the cheese.
edit: and here are some other options: I notice that the unprocessed one is grain-free, vegetarian and has significantly less sucrose. I don't know if any of that makes it more or less healthy, but they're significant differences nutritionally.
If you look up how to calculate the glycemic index of a meal, the formula treats each meal component's glycemic index as a proportion of the total meal's glycemic index.
But the above example shows that the body doesn't treat food in that manner - the relatively low carb, higher fat cheese didn't smooth out the higher proportion carb count of the toast.
In the paper, the largest carbs for the ultraprocessed meal was instant mashed potatoes, while the non-processed meal had bananas as the largest carb source followed by craisins/cranberries.
The high carb foods in the unprocessed meal are paired with fiber.
The high carb foods in the ultraprocessed meal are NOT paired with fiber.
The fiber slows the rate of carb intake.
Same thing occurs with protein - same amount of ground beef and steak, ground beef meal will result in faster amino acid ingestion than the steak meal. No idea if there are any pros/cons of the faster ground beef ingestion, but there is a difference in how the digestive system processes the two meals.
> I know somebody who got really into blood glucose monitoring, and she tells me that the order in which she eats a meal affects how much it spikes her glucose. So if she eats a piece of toast followed by a piece of cheese, it causes her a bigger glucose spike than she'd get if she eats the cheese first and then the toast.
This is what I read in a book about glucose. So I went ahead and measured. I found it not true, at least in my case. The recommendations of eating salad before your meal do nothing measureable for my glucose spikes.
Before we come to a final conclusion on this, we need to reexamine the NOVA food classification system. It holds some rather baffling contradictions. For instance, if you buy a deep fryer and a mandolin slicer to make your own potato chips at home, they're classified as processed foods. But if you buy a bag of plain potato chips (ingredients: potatoes, oil, salt) they're classified as ultra-processed.
This whole concept just doesn't make sense to me - this study included peanut butter and jelly as part of the "highly processed" meal and cheese as part of the "minimally processed" meal. I don't think that either peanut butter or jelly is more processed than cheese.
They matched water content between the meals, so I guess only the ultra processed one required additional water to match the natural water content of the less processed one.
American cheese slices, Velveeta, Cheese Whiz, cheese spreads, nacho cheese are all NOVA group 4 ultra processed because they are industrial reformulations with added ingredients (like emulsifiers). Your average cheddar isn't.
And? For an "average cheddar" you still have to heat the milk, add enzymes, and age it and at the end you get something entirely different. Sounds like "processing" to me, or to use your words, "industrial reformulation."
This is a good question but not an invalidation of the study. People underestimate the cost of doing large scale surveys, first year researchers become painfully aware of it. There are lots of research were you try to get a quantitative result cheap. But most costs a lot of money (the big studies are usually very well spent money imho)
Note that fiber is not part of that list. Stripping out fiber essentially means that our gut microbiome is starved. Not coincidentally, it also means that these foods are much less prone to spoilage.
> The non-UPF and UPF test meals were closely matched on meal weight, energy, energy density, macronutrients, available carbohydrate, glycaemic index and load, total dietary fibre, sodium and water (all ≤1.6% deviation between meals; Fig. 1b).
So they did match glycemic index, which the article omits.
I bet a lot of this is psychosomatic, you expect some food will give you fast energy so your body thinks that means you need it and releases insulin.
But these examples have different glycemic indexes, which the study matched for.
plus all of the options that are complete unknowns which, in biology, is probably close to 99.999%
I know somebody who got really into blood glucose monitoring, and she tells me that the order in which she eats a meal affects how much it spikes her glucose. So if she eats a piece of toast followed by a piece of cheese, it causes her a bigger glucose spike than she'd get if she eats the cheese first and then the toast.
Looking at the two meals in the study: if I sat down to eat the processed one, I'd probably start with the veggie straws. If I saw down to eat the unprocessed one, I'd almost certainly start with the egg or the cheese.
edit: and here are some other options: I notice that the unprocessed one is grain-free, vegetarian and has significantly less sucrose. I don't know if any of that makes it more or less healthy, but they're significant differences nutritionally.
But the above example shows that the body doesn't treat food in that manner - the relatively low carb, higher fat cheese didn't smooth out the higher proportion carb count of the toast.
In the paper, the largest carbs for the ultraprocessed meal was instant mashed potatoes, while the non-processed meal had bananas as the largest carb source followed by craisins/cranberries.
The high carb foods in the unprocessed meal are paired with fiber.
The high carb foods in the ultraprocessed meal are NOT paired with fiber.
The fiber slows the rate of carb intake.
Same thing occurs with protein - same amount of ground beef and steak, ground beef meal will result in faster amino acid ingestion than the steak meal. No idea if there are any pros/cons of the faster ground beef ingestion, but there is a difference in how the digestive system processes the two meals.
This is what I read in a book about glucose. So I went ahead and measured. I found it not true, at least in my case. The recommendations of eating salad before your meal do nothing measureable for my glucose spikes.
*assuming the same ingredients as your home cooked example, which i think is your point, right?
https://www.nature.com/articles/s42255-026-01619-4
It's very likely you're not going to finish your plate.
Example: five years, 10000 participants, $170 million https://www.nih.gov/news-events/news-releases/nih-awards-170...