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Comment by esperent | original | Food processing influences metabolism and brain activity
[−]esperent · 2026-10-10 Sat 07:33 UTC · link
From the actual study:

> 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.

[−]tancop · 2026-10-10 Sat 08:26 UTC · link
That means the only options left are micronutrients, specific additives or psychology.

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.

[−]eudkfkriEir · 2026-10-10 Sat 09:07 UTC · link
> That means the only options left are

plus all of the options that are complete unknowns which, in biology, is probably close to 99.999%

[−]nrclark · 2026-10-10 Sat 09:10 UTC · link
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.

[−]canucker2016 · 2026-10-10 Sat 09:38 UTC · link
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.

[−]jwr · 2026-10-10 Sat 09:58 UTC · link
> 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.

[−]bilsbie · 2026-10-10 Sat 11:23 UTC · link
I got a cgm and found the exact same thing. A piece of cake after a protein and fiber containing meal didn’t move my blood sugar at all.

On the flip side I seem to gain the same amount of weight regardless of what my blood sugar does.

[−]djmips · 2026-10-10 Sat 12:56 UTC · link
the example was cheese, not a salad.
[−]gniv · 2026-10-10 Sat 10:16 UTC · link
This is the main thing of Jessie Inchauspé. One of her many videos on the subject: https://www.youtube.com/watch?v=HEEUrIQ_3O4
[−]PowerElectronix · 2026-10-10 Sat 09:14 UTC · link
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.
[−]esperent · 2026-10-10 Sat 10:13 UTC · link
Isn't that what glycemic index means though? How quickly the sugar gets released?
[−]irthomasthomas · 2026-10-10 Sat 14:02 UTC · link
Not really, chemical sweeteners have no sugar, but still trigger an insulin response.
[−]Ostrogoth · 2026-10-10 Sat 19:35 UTC · link
My understanding is that while there is a small insulin response, existing research so far shows it’s a neutral or a very small effect. (https://www.strongerbyscience.com/should-you-avoid-artificia...)
[−]andor · 2026-10-10 Sat 09:53 UTC · link
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.

[−]mpalczewski · 2026-10-10 Sat 11:19 UTC · link
And chewing. How fast it is eaten is likely affected.
[−]simpsond · 2026-10-10 Sat 13:21 UTC · link
Similar to “The Milkshake Study”