trying to understand insulin

[wbsgn12]

Not trolling here, I'm honestly baffled about this argument...

If we assume calories in, calories out for weight loss/gained (as Lyle McDonald has detailed) then what is the 'insulin' and keto argument for weight loss?

Specifically, paleo minded people claim that if you don't eat carbs you won't spike your insulin and store extra fat, and your body will use stored fat for energy. The KSU professor who lost weight from the 'vending machine' diet a couple of years ago (in my opinion) completely invalidates this theory.

So what level of validity, if any, can be assigned to the 'don't eat carbs and spike insulin' argument? It seems to be completely invalid--are its supporters just outright ignorant, or is the issue more nuanced than I give it credit for?

[Jordan Feigenbaum]

The "insulin" theory is invalid if you're taking it literally, i.e. "keep insulin low"= weight loss, as insulin is actually released when you think about food, when you eat anything (carbs or not), and throughout the day when you need to keep blood sugar in check. The real "neat" part of the argument within, or stemming from the "insulin hypothesis", if you will, is that when people do go low carb for fear of spiking insulin they consume less calories. Moreover, certain studies have been done showing somewhat improved compliance compared to their high carb/low fat or other dietary invervention counterparts. Other studies show improved weight loss, which may be a function of better compliance OR the fact that because these diets are low in carbohydrates and thus, higher in protein and fat, the net effect of the diet on the metabolic rate and total daily energy expenditure (TDEE) changes. Thus, perhaps there is some metabolic benefit to a) eating a low carb diet, and/or b) eating a high protein diet, and/or c) eating more fat as compared to doing a more "conventional" diet. Similarly, there appears to be a spontaneous reduction in energy intake with a low carb intervention due to increased satiety, lower food reward/palatability, and (as mentioned earlier) better compliance with a low carb diet. Are any/all of these things affected by insulin signaling? Certainly. However, chalking all the benefits up to simply "lowering insulin" is foolish and most good thinkers in the Paleo/Low carb world know this.

It doesn't make it any less efficacious though.

[Adam Skillin]

The "insulin" theory is invalid if you're taking it literally, i.e. "keep insulin low"= weight loss, as insulin is actually released when you think about food, when you eat anything (carbs or not), and throughout the day when you need to keep blood sugar in check. The real "neat" part of the argument within, or stemming from the "insulin hypothesis", if you will, is that when people do go low carb for fear of spiking insulin they consume less calories. Moreover, certain studies have been done showing somewhat improved compliance compared to their high carb/low fat or other dietary invervention counterparts. Other studies show improved weight loss, which may be a function of better compliance OR the fact that because these diets are low in carbohydrates and thus, higher in protein and fat, the net effect of the diet on the metabolic rate and total daily energy expenditure (TDEE) changes. Thus, perhaps there is some metabolic benefit to a) eating a low carb diet, and/or b) eating a high protein diet, and/or c) eating more fat as compared to doing a more "conventional" diet. Similarly, there appears to be a spontaneous reduction in energy intake with a low carb intervention due to increased satiety, lower food reward/palatability, and (as mentioned earlier) better compliance with a low carb diet. Are any/all of these things affected by insulin signaling? Certainly. However, chalking all the benefits up to simply "lowering insulin" is foolish and most good thinkers in the Paleo/Low carb world know this.

It doesn't make it any less efficacious though.

Great synopsis. To add my thoughts, if you'll allow it:

I think the whole insulin thing has become a common straw man argument against low carb. Even Taubes never said that insulin is a bad thing. Just that chronically elevated levels from steady high intake of carbohydrate could be a potential cause of insulin resistance. I think the Kitavans are one of many black swans to that particular hypothesis, but a lot of people want to throw out the baby with the bathwater. If your body sub-optimally partitions nutrients to the adipose tissue vs. other tissue, you get to be overweight and malnourished at the same time, right?

Do you have another theory about the mechanism behind insulin resistance? Oxidized polyunsaturates? Carbohydrates with broken cell walls? Aliens?

[gatorinexile]

That first sentence is epic; and I mean epic as in a long poem, the way it keeps going on and on and avoids being a run-on through brilliant use of punctuation that makes it easy to consume and allows it to carry a conversational tone with direct language that conveys the knowledge and confidence of the author while simultaneously enlightening his audience without a hint of being condescending.

My (failing) attempt at imitation above is the best form of flattery.

Can't wait for the book.

[madmaxaus]

In my experience 90% of people talking about avoiding 'insulin spikes' misunderstand a) what insulin actually is, and b) the role it plays within the body.

Chalking up weight loss/body composition entirely to a hormone response is pretty ridiculous really, we know insulin plays a large role in the storage of glucose, amino acids and fats, however this belief that insulin immediately turns any carbohydrate we eat into fat simply isn't true.

There are a lot of variables in play in terms of body composition/weight loss, and as Jordan said it's highly possible that a great number of the benefits of low carb diets are better compliance and, well, you're eating less, you will lose weight.

I sometimes use an extreme analogy to explain this to bro's at the gym, testosterone is the hormone most readily associated with muscle growth, however we know full well that when getting enough protein, carbs + fats, that we're not getting gains in strength + size etc purely due to increased testosterone levels. Likewise we don't lose bodyfat simply by reducing insulin.

[Paul1]

So what level of validity, if any, can be assigned to the 'don't eat carbs and spike insulin' argument?

If you're looking at actual quality science, this pertains almost exclusively to type 2 diabetics or people with impaired glucose tolerance (i.e. "pre"-type 2 diabetics).

But what's hard to tease out is whether it's the insulin spike per se or rather the simplicity of typical diets that's the problem -- i.e. if you survive on corn syrup and white bread you're getting insulin spikes but it may actually be the nutrient components themselves and not only the spikes that are 'bad'.

[Jordan Feigenbaum]

Do you have another theory about the mechanism behind insulin resistance? Oxidized polyunsaturates? Carbohydrates with broken cell walls? Aliens?

A combination of oxidative stress affecting the insulin receptor (IR), misfolding of the insulin peptide in overactive B-cells of pancreas, cells with mutated forms of IR due to AGE's (advanced glycation end products), GLUT-4 receptor mutations. All sorts of things.

[Adam Skillin]

A combination of oxidative stress affecting the insulin receptor (IR), misfolding of the insulin peptide in overactive B-cells of pancreas, cells with mutated forms of IR due to AGE's (advanced glycation end products), GLUT-4 receptor mutations. All sorts of things.

Okay, so what causes those things? Aliens? Excessive fructose:glucose ratios? Rancid vegetable oils? Charred meats?

[Jordan Feigenbaum]

Okay, so what causes those things? Aliens? Excessive fructose:glucose ratios? Rancid vegetable oils? Charred meats?

The question isn't what causes these things, as lots of "things" or events cause these changes to precipitate. Rather the question is what thing or event in particular causes lots of these issues by itself. I don't know the answer other than multi factorial

[gtl]

Okay, so what causes those things? Aliens? Excessive fructose:glucose ratios? Rancid vegetable oils? Charred meats?

I love charred meats. Especially my chicken thighs. If there isn't charring, they aren't done yet.