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Showing posts from September, 2014

Disqus and moderation

Just a quick note.  I switched to Disqus quite a long while ago now due to Blogger's utterly inadequate moderation options.  I do have link moderation on.  I also have moderation on for first time commenters.  I try and "whitelist" people rapidly, as a goal of switching to this comment platform was to keep the discussion going even if I wasn't around to participate.  I think this has worked well on the whole. Danged if I know why some whitelisters still have posts with links held up and some don't.  This appears quite random on my end.  But there are quite a few who simply escaped my notice to be whitelisted, and to those I do apologize.   If your comments do not seem to appear or seem to always go to moderation and you think this is an error, it probably is.  Let me know in comments or via email (carbsane at gmail dot com) so I can fix that!       :-)

Mechanical Work, ATP, and Macronutrients (and Thermodynamics)

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[Blogstress note:  this article is not similar to that in AARR recently mentioned here]  In the background here I've been doing a lot of thinking and writing on thermodynamics and how the body uses food to produce internal energy to "do stuff".    In the end, we "burn" the macronutrient molecules in our food to release the chemical energy stored in those molecules, and ultimately we use that energy to do "work".   I've said we can mostly ignore entropy in the context of the human body, but in chemical thermodynamics we have the concept of Gibbs free energy:  G.   Most importantly in chemistry, we are concerned with the change in free energy of reactions: ΔG rxn  =    ΔH rxn    - T ΔS rxn ΔH rxn  = change in enthalpy (energy)    ΔS rxn  = change in entropy  ΔG rxn  = change in free energy Free energy is the energy available to do work.  For example to move things such as the piston in an engine, an electron through a wire, or

Alan Aragon Research Review ~ Answering some questions about Thermodynamics

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I'm once again honored to contribute to this month's edition of Alan Aragon's Research Review.   This time I was interviewed and answered the following questions:   This is premium subscription content, but AARR is always worth the price in my opinion!   Plus you'll get access to all archives (including past contributions from yours truly from the May-June issues of 2013 and 2014). I missed getting to have my dedication in there, as I didn't think of it until after submission, but I wanted to dedicate the article to my grad school advisor Dr. Owen F. Devereux.   Dr. D died a couple years back or I would have been proud to send him my writings on thermodynamics.  He wrote a book called Topics in Metallurgical Thermodynamics that was his main area of research.  I called it the bane of my grad school existence, but really it wasn't.  Through applying the concepts of that book to my research I really learned and understood thermodynamics.  Folks often w

It's Question Time Again ... Saturated Fats

I have a few questions, but will stick to two.  Feel free to chime in with anything even remotely related! Also, let me preface this by stating that I haven't had the time to deeply digest the various studies that have come down the pike lately exonerating saturated fats.  Any summaries or links to summaries would be greatly appreciated in this regard.  That said ... 1.  Has there ever been an RCT -- or even an uncontrolled trial -- where saturated fat intake was increased on an absolute level (preferably on a weight stable diet) and improvements were seen in cardiometabolic risk factors (or other health measures)? 2.  It is my understanding that mostly the effect (or lack thereof) of saturated fats have been assessed mostly in that 30-to-40% total fat range of the typical Western diet which usually puts sat fat in the 10-15% range.  Would you say this is correct?  If not, are there studies comparing a true low saturated fat diet to a high saturated fat diet?  I'l

Cholesterol or Inflammation?

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I wanted to share this study with my blog readers that I had found and shared a bit of on Twitter a little while ago.  This has been prompted by ongoing discussions there and elsewhere on social media regarding blood lipids.  By "cholesterol" I am of course using the general term that in today's terms refers mostly to the low density lipoproteins or LDL. C-Reactive Protein A Simple Test to Help Predict Risk of Heart Attack and Stroke This is not so much a study as a communication.  It is also on the "Cardiology Patient Page" of the journal Circulation , and as such quite readable.  I'd suggest any and all interested do so as I don't really have the time to go in depth into the entire thing.

It's Official: Paleo is NOT Ancestral

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not paleo The underlying premise of the paleo diet is that we are supposedly consuming foods that our physiologies did not evolve to consume.  In order to get our diets back into concordance with evolution, it is necessary for us to look back. Waaaaaay back.  Nevermind that most of the problems are extremely modern -- as in within the past century modern, often even a matter of a few decades modern.  No ... we must look back millenia and tens of those to the paleolithic times.  Because ... evolution. But even since I first heard of the paleo diet, and began reading about all of these remote ancestral tribes and cultures, there has been this nagging voice asking me how these populations can be translated back into the paleolithic.  Some of these tribes are decidedly neolithic despite their "primitive" cultures.  Any domestication of animals or cultivation of vegetation would be counter to the HG existence we are told we evolved through.  So in addition to looking to re

Disqus & Weston A. Price

Just a heads up here.  For some reason Disqus comments are not loading on my end.  Therefore I can read them in my dashboard but have been unable to respond today.  Hopefully this clears up as I have responses to many! Meanwhile since I'm making a post ... I recently -- finally! -- got around to getting a copy of Weston A. Price's Nutrition and Physical Degeneration .  What I've read thus far has been rather underwhelming to be honest.  In addition I find parts to be quite difficult to read due to the overt racism (is it just me?) in many of his descriptions.  In any case, here's a question for you all.  Is this it for Price's writings or are there more in depth writings available somewhere from which various parts of this book were culled?  Thanks in advance!

Some comments on the Bazzano "LC" vs "LF" Study

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So as the weighing in continues regarding:   Effects of Low-Carbohydrate and Low-Fat Diets  (full text) I thought I'd add a little bit to the mix.   First, I do believe the low carb advocates hailing this as any sort of endorsement for their high saturated fat, high animal fat, eat a ton of food, ketogenic or paleo diets need to all watch this entire video  of Lydia Bazzano discussing the diet:

Channeling Nina Teicholz: Latest LC/LF Study Should Be Ignored

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I'm sure by now you've heard ... low carb "bested" low fat once again in a gold standard randomized controlled clinical trial.  As usual, some weighed in even before the full article was published, but I guess this is to be expected these days. Before discussing this study, perhaps next week, I wanted to point out that by the standards of Big Fat Surprise author Nina Teicholz, this study should be summarily dismissed.  Why?  Well: Not Representative of the General Population It was conducted in 148 obese adults of which 88% were female and 51% were black. Thus the results are not applicable to the general population. Teicholz relegated a well designed and implemented 2 year RCT on the Mediterranean diet to a footnote in her book for this reason. I discussed this in detail here , which was prompted by this footnote in BFS:

A Question about the latest diet study ...

As you may have heard there's a new LC vs. LF diet RCT out there.  I'll have more to say about that when some time frees up, but I have had a chance to look at the full text and it is quite the horribly conducted study -- at least by the description put forth in a fairly highly regarded peer review journal.  (disturbing ....)   In any case, the LC group was instructed to keep carbs under 40g per day.  If you arm a person with some tables of carb content or links to online databases, etc., this is a pretty straight forward and "simple" task.  By that I mean, disregarding any issues with compliance, the task remains an easy and straightforward one. The LF group was instructed to reduce total fat to a maximum of 30% of calories and sat fat to a maximum of 7%.  We are then told that no calorie goals were specified (for either group). Pray tell,  how does the LF group accomplish their goal?