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Alan Aragons Research Review August 2013 [Back to Contents] Page 1
Copyright Augist 1st, 2013 by Alan Aragon Home: www.alanaragon.com/researchreview Correspondence: firstname.lastname@example.org
2 Clearing up common misunderstandings that
plague the calorie debate, part 2: letters from the edge. By Alan Aragon
5 Effects of fructose-containing caloric sweeteners
on resting energy expenditure and energy efficiency: a review of human trials. Tappy L, Egli L, Lecoultre V, Schneider P. Nutr Metab (Lond). 2013 Aug 13;10(1):54. [PubMed]
6 Preventing eating disorders among young elite athletes: a randomized controlled trial. Martinsen M, Bahr, R, Brresen R, Holme I, Pensgaard AM, Sundgot-Borgen J. Med Sci Sports Exerc 2013. DOI: 10.1249/MSS.0b013e3182a702fc [Epub ahead of print]
7 The effects of pre versus post workout
supplementation of creatine monohydrate on body composition and strength. Antonio J, Ciccone V. J Int Soc Sports Nutr. 2013 Aug 6;10(1):36. [Epub ahead of print] [PubMed]
8 Significant effect of a pre-exercise high-fat meal
after a 3-day high-carbohydrate diet on endurance performance. Murakami I, Sakuragi T, Uemura H, Menda H, Shindo M, Tanaka H. Nutrients. 2012 Jul;4(7):625-37. [PubMed]
10 Challenging the protein intake guideline of 1 g/lb.
By Alan Aragon
13 Whats the ideal 6-set routine?
By Alan Aragon
Alan Aragons Research Review August 2013 [Back to Contents] Page 2
Clearing up common misunderstandings that plague the calorie debate, part 2: letters from the edge. By Alan Aragon
Revolution, or empty speculation?
I was tempted to title this installment Part Taubes instead of Part 2 since Im going to focus primarily on his recent high-profile publication in the British Medical Journal (BMJ).1 At the heart of his essay, Taubes is challenging the idea that obesity is caused by overeating. Instead, he postulates the converse that overeating is caused by obesity. Furthermore, he asserts that obesity is a hormonal, regulatory disorder rather than a condition that can be manipulated by caloric balance. He even goes as far as calling the mainstream scientific view of obesity the energy balance hypothesis, implying that the modulation of bodyweight through thermodynamic principles is merely speculative. As you can imagine, this set off a wildfire of dissent from academics who are more familiar with the current data than Taubes is. Perhaps this controversy was intentional on some level who knows. Whats clear is that Taubes is amazingly good at being a journalistic provocateur. The problem I see is that he plays this role by omitting or ignoring large segments of the body of scientific evidence. Jimmies a-rustlin in the mail
Getting your jimmies rustled is internet-speak for getting anywhere from upset to infuriated. Im certain that many researchers read Taubes essay in awe-stricken incredulity, with steam coming out of their ears. Im also certain that many of them wondered how Taubes essay made it past peer-review. I would chalk this up to Taubes political genius, and also the tendency for all publications even academic journals to strive for greater exposure, even if its from controversy that lacks a rigorous evidence basis. If its framed as an opinion, or in Taubes case, an essay, then it has earned a pass of sorts. To our benefit, BMJ published a handful of letters of disagreement, so lets dig into each of them.
John S. Garrow, former University of London professor
A very short letter by Garrow flatly counters that energy imbalance in obesity is not just a hypothesis.2 Ill quote nearly the entirety of his letter since its actually more like a little blurb of advice (my bolding for emphasis):
Itistruethatclinicaltrialspublishedin1907werepoorsciencebecausetheenergyintakewasnotmeasuredreliably.However,in197088agroupofclinicalscientistsattheMedicalResearchCouncilatHarrowpublisheddata fromwhatwasat that timetheworldsbestequippedunit forresearchonhumanobesityand related diseases. Taubes and Peter Attia are planning tofundhighquality researchaboutobesity.Perhaps theyshouldreadtheHarrowdatabeforetheystart.TheevidenceproducedbytheHarrowgroupconvincedmethatobesityiscausedbyanenergy imbalance.2 If Taubes and Attia were also convincedthat it is not just a hypothesis, but hard evidence, it mightsavethemalotofmoney.
Garrow references a book he wrote,3 wherein he discusses obesity research done in the 1970s & 1980s by the Medical Research Council. Garrows underlying message to Taubes is that his Nutrition Science Initiative or NuSi (nusi.org) project is essentially a waste of time and resources. I would have to concur. It seems that the underlying agenda is to confirm pre-existent beliefs that carbs are the bad guy in the war against obesity. This is not an implausible hunch, since the founders of NuSi (Gary Taubes and Peter Attia) are well-established low-carbohydrate diet extremists. Attia has stated explicitly that he eats no more than five grams of sugar per day.4
Further evidence of NuSis biased agenda comes from something I witnessed myself. Jamie Hale, a friend and colleague of mine who specializes in behavioral nutrition and cognitive science, approached Gary Taubes and offered to help NuSi by conducting studies on the cognitive & behavioral aspects of overeating. This would have been great since a half-century of controlled research has consistently demonstrated that a caloric deficit is the single most important factor influencing weight loss, and more recently, that sufficient vs. insufficient protein influences the nature of that weight loss.5 What we need a better grip on are the factors that influence eating behavior. Taubes would have none of that. Hes apparently bent on seeking confirmation of his flawed and oversimplified carbsinsulinobesity model. Richard C. Cottrell, Director of the World Sugar Research Organisation
Cotrell lays out several contentions with Taubes article.6 First, Taubes falls into a circular argument based on incorrect premises and unproven assumptions. His claim that increased sugar consumption is responsible for the worldwide increase in obesity is false since the food and agricultural organization research shows that human sugar consumption has been steady for the past 40 years. I agree with this point. Its not just some cheap ploy from the sugar industry. This claim aligns with data from the USDA/ERS data showing that caloric sweetener consumption since 1970 comprises less than 1% of total caloric increase.8 Specifically, only 42 kcal out of a total of 445 kcal
Alan Aragons Research Review August 2013 [Back to Contents] Page 3
increase from 1970 to 2010 has come from added sugars to the diet. To quote the actual WSRO report, the three key findings are as follows:7
1)Worldwide trenddatadonotsupport thewidelyheldviewthat refined sugarasavailable for consumptionhas increaseddramaticallyoverthelast4050years.
2)Attheworldlevel,bothabsoluteandrelative(%energy)fromrefined sugar have remained relatively stable during a periodwheretotalfoodenergyavailableforconsumptionhassteadilyincreased.
3)Atregionallevel,anysmallincreasingtrendsinrefinedsugaravailability are dwarfed by the large increases in total foodenergyavailableforconsumption.
Secondly, Taubes claim of carbohydrates being uniquely obesogenic in healthy/normal individuals via insulin-mediated means is simply incorrect. For anyone who has not yet done so, I highly recommend reading James Kriegers article series titled, Insulin: an undeserved bad reputation.9 James goes into great detail, using abundant research and sound logic to dismantle the insulin-to-obesity model.
Furthermore, the claim that obesity results from the efficient conversion of carbohydrate to fat is false. Indeed, the hepatic conversion of carbohydrate to fat (de novo lipogenesis, or DNL) is a minor and highly inefficient pathway to the accumulation of body fat. To illustrate this, Ill quote a review by Saris:10
Recently, a combination of wholebody indirect calorimetryand isotope measurement of de novo hepatic lipogenesisshowed that de novo hepatic lipogenesis of 38 g/d wasstimulated by 4 d of excess 50% carbohydrate energy intake(24).This totaldenovo lipogenesisrepresentsasmall fractionofboththesurpluscarbohydratesingested(360390g)
Therefore, Taubes is boldly dishing out factual errors upon which his case rests tenuously. Cottrell makes the valid point that Taubes dismisses positive energy imbalance as merely a hypothesis of obesity since attempts to alleviate the obesity problem have been unsuccessful overall. This is a hasty assumption based on the idea that the treatment is false rather than dieters failing to carry out the treatment. Another good point Cotrell makes is that Taubes alternative explanation for the pathogenesis of obesity is based on anecdote rather than objective evidence. Ben Bradley, general practitioner at the Meuchedet Health Care Organisation
Bradley challenges Taubes idea that there are two competing hypotheses excess energy intake versus a hormonal disorder.10 Calling it a disorder would imply a pathological derangement of normal function. The accumulation of excess body fat is simply a rather normal, and expected biological consequence of continued storage of (wait for it) excess total calories. I would additionally question why Taubes believes that a der