Strange but True - Reheated Pizza

I’ve noticed this for a few years and wanted to throw it out there for fun.

Reheated Pizza Hut pan pizza (via oven reheating) has a different glycemic profile than fresh Pizza Hut pan pizza.

We get pizza once a week. I love it. When I eat fresh Pizza Hut pan pizza (pepperoni), I have to split the bolus 50-50 over 90 minutes or so, depending on how competently the teenagers covered it in cheese. When I reheat it in the oven (plan-overs for the win!) the next day, I have to take less overall insulin, and all of it up front.

My theory is that grease absorbs into the cardboard in the fridge overnight, and some more cooks off during reheating. The cheese is certainly less stringy on day 2. This reduction in grease causes a different glycemic effect?

Anyone else notice this? I’ve committed myself to the true, scientific study of pizza because, like I said, I love it.


Following. I love cold refrigerator pizza, wouldn’t hurt to compare that too.


Sounds like a very good hypothesis!

You better get busy with your research.

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I’m taking Day 8 bg for a spin today: 2 cups of coffee, pizza, cheese sticks, chocolate pb ice cream in a waffle cone, mozzarella sticks…it’s been a good day and I’m not even to snack time yet!

I gotta gain weight while I can before my basals get all wonky on me!

Update: snack time will be nachos. With any luck, I’ll need ginormous underwear bc of how unlimited I’m living!


What is going on here? Now I feel like I’M the one who has missed something…

Have you been brainwashed??

We can’t do Pizza Hut any more because of gluten, and I’m not sure that wouldn’t be a dealbreaker—a gluten free crust— but I certainly would like to be able to join in on the “family feeding frenzy” that goes on around pizza here (grossest advertising words ever, by the way).

Maybe I’ll test out a gluten free pizza… in the name of science…

Just don’t eat it cold! :stuck_out_tongue_closed_eyes:

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As much as I love cold pizza, never have I been tempted. No more cold pasta leftovers either… cold, gluten free leftover pasta… also no longer a thing. :cry:

Interesting idea! Here’s another: sorry for not citing but some studies have shown that cooling cooked starches increases their resistant starch content, thus lowering their GI. Most studies focus on potatoes and sometimes also pasta. Pasta is primarily wheat flour. And so is pizza crust. So maybe the same thing happens with chilled pizza crust.

OK, here’s a cite, in a hurry.

Not a scientific paper but looking at the same idea:

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Interesting!! I’ve never seen this written about before!

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Ugh, yes. Good-bye, yummy pasta salads.

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:rofl: wow… I had forgotten about those.

By coincidence, last night I watched a BBC program called “The Truth About Carbs,” and while I had issues with a number of its assumptions, it did give this somewhat simplified explanation for the cooling=resistant starch process: “A starch molecule is made up of a long chain of sugar molecules joined by bonds, and when you digest starch, your enzymes break those bonds and give you individual sugar molecules. And when food is cooked, and then cooled down again, fats and oils in the surrounding food attach themselves to the starch molecule, and that makes it harder to digest. And then, if you take that cooked food and heat it up again, more fats and oils attach themselves to the starch molecule, and that’s one of the ways that we get resistant starch.”

Although the program focused a lot on Type 2, the context here was increasing the amount of resistant starch to prevent weight gain. Reducing BG rises wasn’t mentioned.


@Beacher that is a great explanation.

I have noticed this with rice and potatoes. Usually we cook rice will some olive oil and the potatoes will usually have butter on them post cooking.

When I am on time for dinner, I will spike more from the carbs and have to pre-bolus earlier than when I am late for dinner and need to re-heat my food.