36 How To Become Insulin Resistant (The Paleo Way) 2
My channel viewers are well familiar with the famous old experiment that placed two men, Vilhjalmur Stefansson and Karsten Andersson, on a diet entirely composed of meat for a whole year. This is a low carber favorite because a superficial reading of the summary from this experiment stated that the meaty dieters got through their year just fine. I think very few low carbers have read this other paper about that crazy experiment. By the end of their year of meat and fat, Andersson had sugar in his urine. (NOTE: Glycosuria was measured following a test meal.)
Sugar in the urine is an indicator of uncontrolled diabetes.
This should cause sugar-obsessed low carbers to do some soul searching because these men consumed only meat. There wasn't a single speck of flour or sugar in their diets that could be scapegoated for this. Even worse for the low carbers, Andersson's urine returned to normal after he resumed eating carbs.
This graph shows you what happened to Andersson's blood sugar. The top line represents his blood sugar (in response to an oral glucose challenge) while eating only meat. The bottom line shows his lower blood sugar (in response to the same challenge) after he resumed eating carbs.
One of the journal accounts of this experiment, which you won't find online, also described the glucose intolerance induced by all that meat and fat. They had a “high sustained level of blood sugar” after a glucose tolerance test, this says. This makes sense in the context of other research on protein, fat, and carbohydrate metabolism.
This very interesting study from 2011 by Martin Weickert and colleagues compared diets that were formulated to match each other except with regard to protein content. One test diet was high-carb, the other high-protein. Weickert found that the high-carb diet resulted in better insulin sensitivity. This is a very valuable study. Let's look more closely at it.
Here you can see the composition of the diets. A few of the Paleo faithful might reflexively blame the non-Paleo ingredients used here like legumes and write off this study in their minds, but they really should take a moment to try to understand what was done here and why. The diets were formulated the way they were to make them as similar as possible while still using reasonably normal foods. Both diets included legumes so that won't work as an excuse to explain this, low carbers. And the high-protein diet had to be low-fat so they could be sure their results weren't really explained by saturated fat. These formulas and diets allowed them to look just at protein in this study. To accomplish this, they had to use some protein powders.
As you can see, this strategy worked because it removed the usual confounders in diet trials. One group didn't lose more fat than the other. There were no differences between them in terms of lean body mass. By keeping their groups so similar, they did a much better study than anything you will see that was paid for with Atkins Foundation money. They really did a great job of focusing just on the issue of dietary protein.
The authors noted the favorable effects of cereal fibers on insulin sensitivity, and they put forth an intriguing conjecture to try to explain them. In light of their finding that their high protein diet seemed harmful for insulin sensitivity, they wondered if cereals helped insulin sensitivity by interfering with protein absorption. This makes sense. Lower protein absorption probably would result in better insulin efficiency, considering the research we've just seen in this video series.
Meat is associated with insulin impairment in ecological studies. In the Rotterdam Study, red meat consumption was strongly associated with diabetes. The authors of this one said that this association was reduced once they adjusted for BMI, but if meat really was harming the insulin sensitivity of the people in their study, that may well have caused them to be heavier.
The Women's Health Study also found an association between red meat consumption and diabetes.
On the island of Sardinia, that famous Blue Zone example of the real Mediterranean diet, high meat consumption was found to be associated with type 1 diabetes.
In this paper about Sardinia, the authors discussed the epidemiology of type 1 diabetes, which is something my viewers know I talked about in video 24, called In Defense of Beans. If you read this, you will notice there is a huge range in prevalence. The places with the most type 1 had 350 times more than the least.
Here is another study which also looked for broad dietary trends in relation to type 1 diabetes. Paleo believers might not believe their eyes when they pause the video and look at this slide, but the relationships between animal foods and cereals with regard to type 1 incidence were found to be strikingly different. Once you study this slide, you might think it would be foolish to even try to associate wheat with type-1 diabetes instead of meat, but realize you aren't thinking like someone who is trying to sell a fad diet. Fad diets require creative interpretations of data. The authors of this one did take socioeconomic factors into consideration, and they believed the association they found between diet and type 1 held up to scrutiny.
One of Loren Cordain's talents is to not let information like that get in his way. There are just too many books to sell to get bogged down in good science that contradicts your marketing ideas. At the bottom, you see Cordain wants you to think wheat can cause type 1 diabetes.
Cordain should acknowledge that at this point, it seems any association of type 1 with wheat is a result of an overlap with celiac disease and is therefore of genetic origin.
And he should understand that in humans, if any foods associate with type 1, they are from animals. It seems like animal foods are associated with type 1 and vegetable foods are not.
Whatever effect meat may have had on the likelihood of become an insulin-dependent diabetic, it seems to come into play early in childhood, according to this study.
In 2009, a systematic review of the association between meat consumption and type 2 diabetes was released. After reviewing 12 cohort studies, the authors found that both red meat and total meat intake were associated with diabetes.
Some are sure to say that that year long meat diet study we saw at the very beginning of this video was based on more of a high-fat diet than a high-protein diet. Now it is time to shift our focus from high-protein intake back to saturated fat. High saturated fat intake has also been associated with insulin resistance and diabetes in many studies. This is a very fascinating study which relates to this indirectly. See if you can follow me here. You may recall from my video 51, which was my video about Neal Barnard's low-fat vegan diabetes trial, that Barnard thought intramyocellular lipids might have some role in causing diabetes. Those are the fats that build up inside of muscle cells. Hang onto that idea and also remember that the highest-fat diet of all high-fat diets is the ketogenic diet, and you know from my videos that this diet mimics the experience of starvation for the body. These two observations now can link up with the “Carnivore Connection” hypothesis from the previous video, which is an evolutionary explanation for insulin resistance. All this comes together in this fascinating study from 2006. A low-carbohydrate, high-fat diet was here compared to short-term starvation, in this case 67 hours with no food. It was found that both the fatty diet and starvation caused fat to build up inside of cells, causing insulin resistance in both cases. The authors, led by Nathan Johnson, said the insulin resistance was a result of carbohydrate restriction in both cases.
Dr. Johnson thought that the free fatty acids unleashed by ketosis were therefore the drivers of insulin resistance. How amazing is this study? Ketogenic diets mimic starvation. The “Carnivore Connection” says insulin resistance would have been a good thing back when food was scarce. The fat inside cells might cause insulin resistance. And now we see that starvation leads to more fat inside cells and insulin resistance.
Free fatty acids had previously been shown to cause insulin resistance both peripherally and in the liver in a dose-dependent fashion.
Under conditions of starvation, this makes sense. The body tries to conserve its glucose for the tissues and cells that absolutely require it, like the brain. Greater insulin concentrations are thusly advantageous under conditions of starvation to keep the brain fueled. But would this be advantageous in your life? This puts the defective carbohydrate metabolism of diabetics in a new light. Perhaps, as the creators of the “Carnivore Connection” hypothesis thought, a tendency to develop diabetes is a modern extension of some past need to maintain high blood sugar.
Back in 1963, low-carb diets were investigated for their effects on free fatty acids and blood glucose. These researchers studied normal people as well as diabetics.
In the normal people, insulin, free fatty acids, and glucose all soared after carbohydrate restriction. These researchers saw a parallel between carbohydrate restriction and diabetes.
Here you see their graphs for insulin and glucose. As you can see, the area under the curve would have been worsened by their low-carb intervention.
Insulin and blood glucose returned to normal after their diets added back carbs.
All the way back in (1963), these researchers drew a link between free fatty acids and insulin resistance, just as Nathan Johnson and the other authors of that 2006 paper comparing low carb to starvation did.
In this recent article, Guenther Boden gives a summary of an interesting study that looked at free fatty acids in the obese and the diabetic. He believed this study demonstrated that free fatty acids are the sole cause of obesity-related insulin resistance. The obese have high levels of free fatty acids which flux out of their fat tissues. In the study which he tells us about, through the use of a drug to clear away free fatty acids, the obese saw their insulin resistance practically vanish. Diabetics given the same treatment also had their insulin sensitivity improve, but to a lesser degree. Free fatty acids are a prime suspect in the development of insulin resistance.
You may recall that I opened the last video talking about the study that is used so often to argue that saturated fat does not impair peripheral insulin sensitivity. This study gives us a very interesting twist on that result. These investigators used formula diets to dramatically alter the proportions of fat and carbs, with one diet having no fat at all and the other having 83% of its calories from fat. Protein remained constant. They fed these diets to healthy men. They, too, detected no effect of the fat on peripheral insulin sensitivity. That is consistent with what we saw in that saturated fat study. The researchers here did, however, notice much higher levels of free fatty acids after the high-fat feedings. Robb Wolf, take note of that. What they found was that under conditions of high-fat feeding, insulin failed to control gluconeogenesis. What does all this mean? How do you become insulin resistant the Paleo way? Based on my reading of this literature, we can see that excess protein causes an increase in gluconeogenesis and a decrease in insulin sensitivity. Excess fat may not as obviously affect insulin sensitivity in skeletal muscle but it causes an inflammatory state through the release of free fatty acids. Excess animal protein combines with saturated fat over time to push those at risk into a state of insulin resistance, and potentially, prediabetes.
If I'm right, this may explain findings like this one. Here, maternal egg consumption was associated significantly and positively with gestational diabetes in this prospective cohort study.
This finding was replicated in two different groups of participants used by the researchers in this paper, with one group in a cohort study and one in a case-control study. This research team was led by Chunfang Qiu. Could it be that the eggs, with their protein and saturated fat, provoke a response programmed by evolution that seeks to conserve glucose for the developing fetus?
Dietary fat hardly seems to be innocent of involvement in insulin resistance. We can see an effect of fat on insulin sensitivity in this overfeeding study. Subjects were overfed to the same degree through excess carbs, and then separately, through excess fat. Protein was held constant, as were the fatty acid ratios. This study did use some real foods. High carb overfeeding actually seemed to improve insulin sensitivity. High fat overfeeding seemed to impair it. The authors did note that they thought the improvement in insulin sensitivity from the high-carb overfeeding was only a short-term effect.
Those circulating free fatty acids have recently been linked to beta cell dysfunction and islet inflammation, as you see in this title, which is a reference to Islet of Langerhans cells. The researchers here suggested a connection to dietary saturated fat.
The effects of fat on insulin sensitivity may not be the same for healthy normal people as for those with metabolic syndrome. Here in a study led by Sergio Lopez, individuals with high triglycerides had worse insulin sensitivity after a meal with fat than after a meal without fat. Saturated fat seemed more harmful here than monounsaturated fat.
Gary Taubes wrote about the Pima Indians and their problems with obesity and diabetes in his terribly biased book. If you look at his references, he found one obscure study by an author named B.A. Swinburn about caloric restriction but he somehow missed Swinburn's paper about the Pima Indians. I wonder why. Let's look at it and try to figure out why Taubes didn't put this in his book. Swinburn and his partners here compared Pimas to Caucasians. Their participants were randomized to either a traditional Pima diet or a modern diet for two weeks.
Here you can see the diets. The main difference was in fat. The traditional diet was much higher in healthy carbs and it was even higher by a little in simple carbs. The modern diet had much less fiber, much more animal protein, and much more saturated fat.
That modern, high-fat diet decreased glucose effectiveness, which is the measure of the ability of glucose to cause its own disposal. The modern diet caused higher insulin levels and caused a worse performance on an oral glucose tolerance test.
You can see the differences in both glucose and insulin here.
Interestingly, both the Pimas and the Caucasians responded the same way to both diets. Taubes left this study out of his section on the Pima because it clearly showed how much better a high-carb, high-fiber, low-fat diet is for them than a diet lacking in fiber but full of fat and meat.
As you will see in my Cherry Picked Research videos, we rarely see the results of an oral glucose tolerance test revealed in the various studies meant to promote low carb. That's because low carb diets impair carbohydrate metabolism and this is easily demonstrated by an oral glucose tolerance test. You are looking at one low-carb trial that did publish a result for that test and you can see that plasma glucose area under the curve was much worse after a low-carb diet than after a normal diet.
Here's a study published in 2012 looking at low-carb and its effect on blood glucose. The oral glucose tolerance test was the main focus of this study. The authors noticed there wasn't much published research subjecting low carb to such a basic and universally accepted test. This study was especially valuable because they used healthy subjects here, not the diabetic and obese.
There was no reason to wonder about what the actual foods consumed in this one were, as the research team supplied the food themselves.
Triglycerides decreased on the high-fat, low-carb diet, but plasma glucose during the oral glucose tolerance test was much higher.
You can see what I mean in their graphics. This is not desirable, folks. It seems to me that if you have a problem with blood sugar, a low-carb diet is the last thing you should be doing to yourself.
These authors described the transition the body undertakes as it shifts fuels under different feeding conditions.
Of course the body can be fueled by a fatty diet. Your evolved fuel system makes you a flex-fuel vehicle. It's pretty clear which fuel, fat or carbs, is better, though. What is especially interesting to me is that humans have an easier time shifting from a high-fat diet to a high-carb diet than the other way around. This should tell us something about which is more “natural,” if that is what interests you Paleo-minded viewers. A natural diet shouldn't be too hard to get used to, and it is much easier to get used to a high-carb diet than a high-fat diet. It takes more than a week to get the body adjusted to fat.
As top Atkins researcher Stephen Phinney wrote in 1983 in his paper about athletes, the body works hard to conserve carbohydrate during ketosis. Insulin resistance would help to conserve carbohydrate by keeping what little carbohydrate the body has available in the blood where the brain can access it.
The very high levels of uric acid he measured were an expected response on a ketogenic diet, he said. As I have shown you, high uric acid concentrations are associated with insulin resistance and heart disease.
Phinney's paper shows us that the human body adjusts back to a diet with carbs very easily, whereas the transition to ketosis caused by a high-fat diet is a miserable experience. Also, Phinney's study makes it clear that a lot of the weight loss seen in low carb diets is just water loss due to the depletion of glycogen stores. As soon as the body gets its carbs back so it can store some glycogen, a lot of that weight that seemed to have been lost just comes right back. I think that's a pretty dumb way to lose weight.
By now it should be clear to you that high-protein, high-fat diets are linked to impaired carbohydrate metabolism. These diets just don't make sense. Low carbers are against refined grains and added sugar, and that's good, but they stubbornly ignore all this ugly evidence against high-protein, high-saturated fat diets. Don't they understand it is very easy to eat a high-carb diet while avoiding refined grains and added sugars? Can't they see it is very hard to devise a low-carb program that gets away from excess protein and saturated fat?
If the eating of fruits, which have hardly any fat and very little protein, is associated with a reduced risk of diabetes, what does that say about the low carb belief system?
If this cross-sectional study found that higher intakes of whole grains are associated with increased insulin sensitivity, what does that say about the Paleo hypothesis?
Why hang onto ideas that can't predict what happens in reality? Among over 64,000 women in China, legumes and especially soybeans were associated with a decreased risk of type 2 diabetes. Is there any half-baked, stitched together blog post against soy on the Weston Price Foundation website that should be more convincing than this?
These people know they are on the fringe. Sisson's advice is so terrible, it is little wonder that he starts his book with a comprehensive disclaimer.
That permits him to call the work of educated and responsible people “the Conventional Wisdom” and it covers his rear as he refers his readers to the tiny quack brigade at The International Network of Cholesterol Skeptics. Sisson thinks these people are leading intellectuals. Actually, they are a very few people scattered across the world, at least some of whom are of highly questionable standing.
For example, one of them, Barry Groves of the Weston Price Foundation has no formal education in medicine or nutrition at all on his bio except for a PhD from a distance learning school in the US. Read what he wrote at the top. He wants you to know that his school shouldn't be confused with a diploma mill in Spain with a similar name. But publications of the US military want their service members to know that his school is a diploma mill. Mark Sisson has no problem associating himself with people like this because he is no more responsible than they.
Someone else who is incredibly irresponsible is the self-styled “Diet Doctor,” Andreas Eenfeldt. He has personally selected what he has decided is the best of the low-carb and Paleo science. His cherry picked list gives me a great opportunity to show you how bad science is created to support a bad idea. Eenfelt's best material is about to be exposed for the junk it really is. “The Diet Doctor” gets a thorough examination, next.