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Welcome all seeking refuge from low carb dogma!

“To kill an error is as good a service as, and sometimes even better than, the establishing of a new truth or fact”
~ Charles Darwin (it's evolutionary baybeee!)

Thursday, December 16, 2010

Insulin Wars III: Valerie Berkowitz (formerly of Atkins Center)

I thought I would share some thoughts on some of the responses of LC "experts" to James Krieger's excellent series on insulin.  For any who missed them, here are the links  “Insulin…an Undeserved Bad Reputation”, Part 2,Part 3, Part 4Part 5.

Jimmy Moore asked an array of people in LC circles for their thoughts HERE

I'm just going to address one quotation:  

It’s true that the body can store fat even when it has low insulin levels when excess calories from a high carbohydrate low fat diet are stored as fat even if insulin levels are not high. Upwards of 85% of excess carbs turns to triglycerides or fat. The body is less likely to store fat if it is primarily burning fat for fuel.
This perpetuation of the myth that it is excess carbohydrate calories that are converted to fat has got to stop!
 It is simply not supported by the science.  See Jequier and Hellerstein.   

Bottom line, excess calories are excess calories.  It matters not if our TDEE is 2000 calories and we consume 500 calories more entirely in carbohydrates, that the 500 calorie excess came from carbs or fats (or even protein).   A net 500 cals will be stored, as glycogen if stores are depleted, but mostly as lipid from the diet or "recycled" free fatty acids from circulation. 

Regarding fat burning:  The body is constantly burning fats, whether those fats come from diet or endogenous sources (fat tissue or "local" storage in cells) depends on the balance of energy intake and expenditure.

11 comments:

malpaz said...

another winner here :) LIKE THIS! i am sick of hearing people who are so gospel obsessed with low insulin levels...

MM said...

CarbSane,

Thanks so much for doing this series. I have a question, and maybe this is yet another low-carb myth. I remember hearing (sorry I don't remember from whom) that your cells can either burn fat or sugar, but not both. So, if your cells are burning sugar because you're eating a high-carb diet, then they can't burn fat, and all the fat you eat with your carbs will be stored. So, is this not the case? Is it an over-simplification? Is it just that individual cells can't burn both but some cells can be burning fat, while others burn sugar? Thanks so much for the info.

Muata said...

I can't believe how folks are so cavalier in passing out misinformation! The body burns fat for fuel ALL day long, not just when someone is doing LC. The problem with this type of "incorrect" thinking is that there are hordes of folks that have lost "fat" following a LF/HC diet. So, how does Berkowitz explain this? Man, dogma dies hard, eh?

Sanjeev said...

>> Upwards of 85% of excess carbs turns
>> to triglycerides or fat

I've never seen anything that would justify this statement.

If my daily caloric requirement at maintenance is 2,000 calories, then even if I ate 4,000 calories of carbs that would still only be 50% conversion to body fat.

Sounds like an off the cuff statement for the consumption of other cult members.

CPM said...

I am not sure this is related to what they are talking about, but I came across the 85% number recently here:
http://www.ncbi.nlm.nih.gov/pubmed/7598063

Fat overfeeding had higher storage (90-95%)

Frank said...

Carbs don't turn to fat, or a tiny bit only. Their oxidation goes up as crazy (thus imparing fat oxidation) or there is glycogen supercompensation occuring way before de novo lipogenesis occur.

That 85% is totally made up.

Sanjeev said...

what Frank wrote

CPM, please look up the thermogenic/TEF link (down the right side) and ... that looks a lot like the study Matt pointed to some time ago ... anyway, they found
" 75-85% of excess energy being stored"

Not 75-85 % of carbs, but of excess energy. If you read the text (it's free)

The figure on page 25 shows 80% of carbohydrate being stored for the very first day but note
1. only that day
2. they don't say it got turned to body fat

BUT ... page 22 does mention they saw similar changes in fat mass and fat free mass between the groups, though the study wasn't designed to look for that.

my best guess: the first few days the muscles were being topped up with glycogen.

CPM said...

Hi Sanjeev,

I was just suggesting maybe that is where the 85% number came from, not that they were interpreting or presenting it correctly. The mention of “excess carbs” sounded like an overfeeding study.

Do you happen to remember where Matt brought up the other overfeeding study? If it is the one I’m thinking of, I remember I wanted to go back and look at it some more, but now I can’t find it. I think it dealt with the differences in fat and lean body mass from different types of overfeeding.

CarbSane said...

Hi CPM, I think this is what you're talking about:
Fat Futile Cycling from Carb Excess? citing this study.

I think even Taubes only states that as much as "perhaps" 50% of carb is converted. That less is gained from carb overfeeding than fat is a no-brainer. TEF is the thermal effect of the "normal" metabolic utilization of the macronutrients. For carbs to contribute to fat stores we have to expend further energy to synthesize fatty acids and then package the away as triglycerides. So even if the futile cycling described in that post can't compensate entirely, we have to expend some energy. Fatty acids, OTOH, can just be socked away!

Sanjeev said...

CPM, the study I was thinking of is in the post CarbSane linked to.

looks like they are in fact the same study.

William said...

Hi CS, I know it's a little late in the game, but if someone overeats 500 kcal of fat, you are saying they will store as many excess calories as if it were 500 kcal protein? (no influence of TEF, etc.?)

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