This study was discussed on Metabolic Mind:
Note: There’s also a YouTube video, although I had a hard time finding the link
Here’s the study:
https://www.nature.com/articles/s41591-025-03719-2#Sec2
They took “healthy” people and did a ton of testing on them, then gave them some standardized meals and saw what happened:
Way too much information for me to analyze right now, but it shows how different people respond to the same meals.
I look forward to listening! But just off the top of my head (pardon the pun), I wonder why they aren’t looking at insulin response rather than glucose response but maybe they were? Just seems like insulin would be the underlying factor.
I think what they did was run a bunch of tests on the people to gauge their insulin resistance. For instance the “hepatic insulin resistance” and the “adipocyte insulin resistance” are (from what I remember) complex ways of determining these insulin resistances. Then, when they feed them the carbs, they try to determine what happens based on the insulin resistance of the participants. They try to simplify it, like this:
I don’t understand this entirely (why are there 7 people instead of only 6?), as I haven’t read the study yet. But I think what they are trying to show is what happens with those carbs (rice, grapes, potatoes) if you are insulin resistant or insulin sensitive.
I think the real issue is they can give you a CGM, but there is no insulin meter. So, they tried to categorize the participant’s insulin resistance through a number of tests, then see how well those test actually predict what effect carbs would have on them, depending on their degree of insulin resistance.
This shows the huge variability. The AUC = area under the curve, which means they give you food, then you have a response that is measured on the continuous glucose monitor. They look at data for a certain time period, say 2 hours, after you eat. Then they see what your blood sugar level is every so often. They try to determine how much area is under that. So, people who are high for a long time would have a higher AUC than are people who are high but for a shorter time. And it looks like there are people who don’t have any response (the dots near zero):
This where the point about insulin is relevant. Some of the folks who have low AUCs have them because they way overproduce insulin. If these folks where given Kraft tests (take a sugar drink, measure both insulin and blood sugar), you’d see a huge insulin spike. That’s why blood sugar doesn’t go up much.
Could there be folks who don’t get high blood sugar (very low AUC) and don’t have high insulin? I don’t know.
Edit. I drew this up to show the area under the curve. The purple has the highest AUC, the red has lower AUC, and the people near zero are in black:
It’s wild how different people react to the same meals, and your AUC explanation makes sense, showing how some keep glucose low by spiking insulin, did the study mention any long-term risks for people with high insulin but normal glucose, or plans for follow-up research, and I appreciate you posting the visuals since they help make it clearer <3
Downloaded, on tomorrows list. I would have never figured myself out to the level I did without the CGM. First time I did it I was before I started the TKD/CKD thing I do now, so it was pretty uneventful most of the time, now, It showed me WAY more about the way I reacted, different food mixes, recovery time etc.
Everybody should slap one on at least for a month or two if they can’t figure themselves out, especially since the days of needed doctors for them are gone as well as relying on subscription companies that overcharge you and try to rope you into coaching and plans.
I agree about the CGM. I found out that my blood sugar went up and down within an hour if I ate carbs (except real pizza – which caused the longest peaks by far), which makes me wonder if I was outputting too much insulin. I also learned that things like popcorn, which many think are high carb, caused zero blood sugar rise. Also, a soup from an Asian restaurant, which I thought would be low carb because it had no rice or noodles, caused super high blood sugar. My guess is something like cornstarch.
I’m on vacation and trying to look at this, although it takes a lot of brain power. I thought this was interesting:
I would’ve guessed that people of Asian descent would mainly be non-rice-spikers (meaning lower blood sugar after eating rice), and people of non-Asian descent would be rice-spikers, but that’s the opposite here.
I’d love to have a CGM for rice/rice noodles, as I will occasionally eat these, because they don’t affect my digestion. At one point, I was trying a TKD (targeted keto diet), where I ate carbs my first meal (of two) per day, on days I did body weight training. I tried a bunch of sweet potatoes, even spaghetti squash, etc., and most of those caused digestive issues. Rice noodles did not. And sometimes I’d go to a Mexican restaurant that had a meal with a lot of meat, but also white rice. Not much rice, but it helped temper the hot peppers they used.
In the year I had a CGM, I don’t think I ate rice at all back then (2017).
One of the tests they used was SSPG (steady-state plasma glucose):
Which I think is discussed here:
I don’t understand the test (why put both insulin and glucose into the blood? Maybe because they know how much insulin there is?), but I guess the idea is that if you have a higher blood sugar, it’s not going to where it should (muscles, etc.), and therefore you’re insulin resistant, and they use a level of 120 for that.
I haven’t had time to figure out what they do with this, though.
