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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!)

Monday, May 10, 2010

Jorge Cruise Belly Fat Cure & Leptin

I am currently reading Jorge Cruise's Belly Fat Cure book.  I'll post a review of it when I'm done, but he made the following claim about leptin (this is a screen shot from my ebook):



(click on screenshot to enlarge/read)

Now one of these days I'll track down the article I got the screen shots below from, but my recollection of their source was a study where the subjects were fasted for several hours (overnight?) and plasma levels of BG, triglycerides, insulin, and leptin were measured for 6 hours after ingesting equicaloric "meals" of just carb, fat or protein.  (I want to say 1000 calories, but don't quote me on that, and subjects were healthy normal adults).  If memory serves, the carb meal was glucose.  I'll try and update this post if/when I can.



In any case, look at the leptin levels.  For any type of macronutrient, notice that if anything the trend is for leptin to be reduced slightly over the 6 hour period v. baseline.  Another thing is that while the protein group for some reason started with slightly lower leptin levels, the most consistent trend of lowering leptin is seen for the protein meal.  If anything, the carb at least sees a delayed "uptick" of leptin to pre-ingestion levels, while the fat doesn't seem to impact leptin at all until it "tanks" out around 4 hrs post meal.  In any case, those vertical lines represent the variability (standard deviation) in the data while the data points were the mean.  If memory serves, the changes in leptin were not statistically different between macronutrients or over time because of this wild variability.  

So in this respect, sadly, I feel Jorge Cruise has misspoken about leptin and all sugars vs. other macronutrients.

Much of my research and readings about leptin seem to indicate it is a "chronic" hormone related to overall nutritional status and/or level of adiposity rather than an "acute" actor (as insulin mostly is).

1 comment:

Nychelle Bestcasenario said...

Thank you for your article!

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