Paul Saladino· MD
What does cause insulin resistance? At a high level, I think it's pretty clear the main problem here is excess polyunsaturated fats (PUFAs), particularly linoleic acid.
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What does cause insulin resistance? At a high level, I think it's pretty clear the main problem here is excess polyunsaturated fats (PUFAs), particularly linoleic acid.
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Excess PUFAs cause the adipocytes to signal to peripheral cells to become insulin resistant.
for a lot of people it could start with too much of these polyunsaturated fatty acids this is something I talk about in my book as well where does insulin come from and this insulin resistance being behind so many pathologies
but this is one of the key mechanisms by which insulin resistance develops in the periphery is extra leak of free fatty acids from your adipocytes because of congestion of polyunsaturated vegetable oils
in summary linoleic acid is so toxic to humans because it breaks the sensitivity uh for insulin at the level of your fat cells your fat cells control the insulin sensitivity of the rest of your body by free fatty acids we know this very clearly
if your fat cells are insulin resistant they will not take up glucose they will not take up fats they will not grow if they don't grow then they won't release free fatty acids
and then when the fat cells are insulin sensitive they grow they release free fatty acids to the rest of the body which we know constitutively creates insulin resistance
but if you listen to my cgm podcast with the folks from nutrasense you will know that you don't want to have zero insulin signaling all the time you want some insulin signaling and this is why people who may benefit from low carb diets in the short term get fat when they add carbs back because their fat cells are still broken if they are not changing the type of fat they are eating there is nothing more important in my opinion than the fats that you are eating and that what you are eating what it's what you are eating that is eating that is critical
but if you eat polyunsaturated vegetable oils your fat cells get a different signal they remain insulin sensitive they get broken and they get bigger but as they get bigger they start to leak free fatty acids and that free fatty acid leak from those expanding adipocytes that are insulin sensitive when they shouldn't be because you're eating too much linoleic acid makes the rest of your body insulin resistant
how do you make your fat cells insulin sensitive leading to insulin resistance in the rest of the body well one way is by eating too much polyunsaturated fatty acids because it sort of creates more of a more of a signal in the mitochondria of the fat cells that they should be insulin sensitive
if you feed your fat cells stearate and palmitic acid which are found in ruminants red meat your fat cells become insulin resistant they don't grow they don't release free fatty acids in the same way and the signal to the rest of the body is to remain insulin sensitive
if you eat linoleic acid and too many polyunsaturated fatty acids your fat cells are going to remain insulin sensitive they are going to grow and as they grow this atgl enzyme is going to release more fatty
a lot of carnivores are eating chicken and bacon if you're filling your body with linoleic acid you're un you're creating a problem
if you eat linoleic acid and too many polyunsaturated fatty acids your fat cells are going to remain insulin sensitive they are going to grow and as they grow this atgl enzyme is going to release more fatty acids into your blood because the fatty acids are the fat cells are growing and they're leaking free fatty acids in your blood when free fatty acids are found in the blood perpetually then the rest of the body gets the signal to be insulin resistant okay so the fat cells remain insulin sensitive because you're feeding it polyunsaturated fatty acids which we're not supposed to have the rest of the body becomes insulin resistant
this is going to be a little bit of biochemistry about why saturated fat is the best thing for humans from a biochemical perspective and why polyunsaturated fats are the worst things for us and they make us incredibly insulin resistant systemically and why i always talk about vegetable oils causing insulin resistance
your bacon is not healthy for you if it is fed corn because mono and polyunsaturated fatty acids affect the fatty acid composition of pig's adipose tissue and make it much more full of polyunsaturated fatty acids specifically linoleic acid which makes our adipocytes insulin sensitive which makes the rest of our body insulin resistant
my suspicion my hypothesis is that excess amounts linoleic acid create a metabolic havoc and are probably the main factor driving insulin resistance
i think it's polyunsaturated fatty acids specifically linoleic acid that really cause insulin resistance by increasing visceral fat
we have to correct the underlying issue which is excess polyunsaturated fatty acids at a high level
how do you make your visceral adipose tissue insulin resistant you eat stearic acid and i'll show you studies which illustrate this if you want your visceral adipose tissue to grow you feed it polyunsaturated fatty acids
i strongly believe is polyunsaturated vegetable oils specifically linoleic acid causing the mitochondria in our visceral fat to become broken
but the takeaway here is that carbohydrates are not the cause of insulin resistance it is the underlying excess of omega-6 fatty acids which are an evolutionary inconsistency in today's diet
linoleic acid causes pathological insulin sensitivity at the level of the adipocyte
the problem with linoleic acid and this will all make sense very soon when we eat linoleic acid it does not create reactive oxygen species in our cells which means it leaves those cells insulin sensitive especially the adipocytes which means the adipocytes can grow but other cells of our body remain insulin sensitive as well which means that when there is an insulin signal around they take up glucose which means that glucose levels dip and when glucose levels dip precipitously you get hungry
linoleic acid signals to the adipocyte to grow grow grow grow grow eventually that adipocyte as it's insulin sensitive it runs into a problem where it is so full that it starts spewing out fatty acids and this is adipocyte triglyceride lipase atgl and so the theory here is that when the adipocytes get over full i think especially the visceral adipose tissue we get a release an inadvertent release of fats and the inadvertent release of those fats is then signaling to the rest of the body hey become insulin resistant
the adipocytes are poisoned with too much linoleic acid they have grown so big yes that they cannot possibly hold it anymore they're just leaking it
because they are because polyunsaturated fats make your adipocytes more insulin sensitive which means you can stuff more fat and more glucose into your adipocytes but all the while your adipocytes are expanding and expanding and expanding
because polyunsaturated fats are not stable you don't want these in your diet in excess amounts because they hold open the adipocytes they hold adipocytes open by making them insulin sensitive
linoleic acid appears to make our fat cells very insulin sensitive which sounds like a good thing until you realize that an insulin sensitive fat cell grows and gets bigger you don't want bigger fat cells
you have to be really careful with this because it looks confusing glucose transported insulin bound you can see control higher polyunsaturated ratio this is fat cell growth you guys fat cells are growing when you feed them more polyunsaturated fatty acids you don't want this but it looks confusing in the short term if you listen to people who are arguing this theory that don't fully understand the model
as you introduce double bonds into these fat molecules whether it's a monounsaturated like oleic acid or a polyunsaturated like linoleic acid or a polyunsaturated like that that's that's different than linoleic acid even a fish oil we can talk about um an omega-3 um they are preventing the cell from signaling that they are full they are creating essentially inappropriate persistent insulin sensitivity
so there's not so much fad made there's still the nadh being made and the ratio changes um and it makes it harder for the cells to say no to more calories and every double bond makes the problem worse yep so i think that that's was the the next insight that came from the protons concept is that the poly saturates refuse to trigger insulin sickening they will eventually trigger it if you put enough polyunsaturates in eventually the nadh and whatever basic level of fadh that they're producing will eventually combine together to limit calorie ingress but at that point there will still be calories coming through in excess of what the cell needs and we come back to that there will be continued insulin signaling and that will be taking the excess calories and converting it into lipid in the cytoplasm or glycogen in the cytoplasm
i think we're inducing that inappropriately with these evolutionarily inconsistent omega-6 fatty acids
why is the fat cell releasing the free fatty acids and i think it's because people are exceeding their personal fat threshold or there is some inflammatory response in the fat cell predominantly driven by excess omega-6 seed oils linoleic acid that is causing them to release those free fatty acids
it can be pathological in a state of metabolic dysfunction because the membranes of those fat cells are enriched in linoleic acid leading to essentially broken signaling in those fat cells and the fat cells growing too large and spewing out inflammatory mediators that is cytokines etc
how do you break adipocytes i think there's a lot of good evidence this is related to excess linoleic acid consumption in humans
I would say the case is getting stronger and stronger that excess linoleic acid, an extremely evolutionarily inconsistent behavior by humans, is at the root of insulin resistance. Getting rid of these seed oils, decreasing linoleic acid in the human diet, I believe will be the single greatest change in our health moving forward.
is 4-H and E I did a podcast with Tucker Goodrich and Jeff knobs and I've spoken about this repeatedly but there seems to be some pretty good evidence that when there's excess breakdown products of linoleic acid the fat cells can't do hyperplasia meaning they can't divide they can only hypertrophy so you see this broken adipocyte this broken fat cell that is like this guy on Monty Python that just keeps eating and then he bursts you know and he can't you know he just it's just these fat cells grow and grow and grow and they can't divide they just burst and they spew out lipokines they spew out inflammatory mediators and then they also spew out these free fatty acids into the blood
then the second pathway you that it seemed like you were talking about with diabetes is kind of this broken excessive lipolysis and I've spoken about this on my podcast as well in the past because when I've dug into this research it's been really fascinating to look at the adipocyte specifically the fat cells and what happens to them when they're exposed to the breakdown products of polyunsaturated fatty acids like linoleic acid
in a state of pathological insulin resistance you have stuffed your fat cells with way too much polyunsaturated fatty acids which are accumulating in your body you don't get rid of them very easily like you can with monounsaturated or polyunsaturated fats this leads to the fat cells leaking free fatty acids and inflammatory mediators even in the presence of insulin and carbohydrates
the poof is specifically known to block and act as antagonists of the insulin receptor which means that these fatty cells because insulin is the anti-lipolytic agent the main one that we have
So from a whole energy perspective, linoleic acid looks to be very bad. And when we're not producing energy efficiently, we become insulin resistant. It's sort of this cell danger response or at least a a reactive response in the cell saying, "Hey, we're not making energy."
Specifically, when linoleic acid is taken into the cell, one of its peroxide metabolites that it can turn into is a molecule called 4 H&H has been shown to inhibit the fat cells potential for hyperplasia, thus forcing the fat cell to only go down hypertrophy.