Part I: The Journal Article & The Headlines
There is so much about the recent study from principal low carbohydrate advocate Jeff Volek, that this may well be the subject or impetus for several posts here as we close out 2014 -- it is so much more than just the study, but more what it embodies vis a vis the whole low carb/keto schtick. Along with Stephen Phinney and ten -- count them, TEN! -- others who claim to meet the PLOS One standards to be designated as authors, we were brought the following study:
Effects of Step-Wise Increases in Dietary Carbohydrate on Circulating Saturated Fatty Acids and Palmitoleic Acid in Adults with Metabolic Syndrome
In a way this tops off a year of disgraceful behavior on the parts of just about everyone in the IHC who seem hell-bent on deceiving people into adopting their extreme lifestyles. If the science were really so clear, then why can they not address it honestly? There is nothing, N.O.T.H.I.N.G. in this study that supports the following quotes from Volek that have been repeated in multiple outlets too numerous to cite (but I'll link the official press release from his new institution, Ohio State University, the presume source for all further "journalistic" resports):
The finding "challenges the conventional wisdom that has demonized saturated fat and extends our knowledge of why dietary saturated fat doesn't correlate with disease," Volek added.
“There is widespread misunderstanding about saturated fat. In population studies, there’s clearly no association of dietary saturated fat and heart disease, yet dietary guidelines continue to advocate restriction of saturated fat. That’s not scientific and not smart,” Volek said. “But studies measuring saturated fat in the blood and risk for heart disease show there is an association. Having a lot of saturated fat in your body is not a good thing. The question is, what causes people to store more saturated fat in their blood, or membranes, or tissues?
“People believe ‘you are what you eat,’ but in reality, you are what you save from what you eat,” he said. “The point is you don’t necessarily save the saturated fat that you eat. And the primary regulator of what you save in terms of fat is the carbohydrate in your diet. Since more than half of Americans show some signs of carb intolerance, it makes more sense to focus on carb restriction than fat restriction.”
Perhaps Volek is not aware that the favorite Ancel Keys "bashing" study by Yerushalmy & Hilleboe did indeed provide better evidence than his data provided for all fat, for just such correlation between animal fat consumption (higher in saturated fats) and heart disease. Not only that, but plant fats (mainly unsaturated) fats and even carbohydrates were negatively associated with heart disease. See Denise Minger's post on the Y&H Study and Keys where she lists the correlation coefficients. There are statistically zero human cultures on this planet ever who have consumed a high saturated fat diet. NONE.
MacSmiley has posted the following link (direct PDF download) in comments on my prior post on this study. It is a document summarizing one of the funding parties of the study, The Beef Checkoff Program -- involving just about everyone beef, so Big Bovine it is!
When such clearly telegraphed expectations are there, it becomes all the more difficult to believe that funding source had nothing to do with this, especially when the principal investigator has such a long track record of low carbohydrate advocacy.
Speaking of that track record ...
2008: Comparison of Low Fat and Low Carbohydrate Diets on Circulating Fatty Acid Composition and Markers of Inﬂammation
Authors: Cassandra E. Forsythe, Stephen D. Phinney, Maria Luz Fernandez, Erin E. Quann, Richard J. Wood, Doug M. Bibus, William J. Kraemer, Richard D. Feinman, Jeff S. Volek. (italics indicate author of current study)
Funding: The Dr. Robert C. Atkins Foundation
In this study they took 40 overweight men and women with atherogenic dyslipidemia and put them on a VLC diet (C:F:P 12:59:28) or an LF diet (C:F:P 56:24:20) for 12 weeks. The details of this study - presumably providing anthropometrics for the participants - were "described previously" in Comparative effects of dietary restriction of carbohydrate or fat on circulating saturated fatty acids and atherogenic dyslipidemia. Submitted for publication. I found one other paper by this research group citing that study (also with submitted status), but no paper was ever published that I can find. [11/29 EDIT: Finally found the publication as it was referred to on Richard Feinman's blog. Here is the paper: Carbohydrate Restriction has a More Favorable Impact on the Metabolic Syndrome than a Low Fat Diet. I don't have time to edit in any implications of the weight loss differential, etc. from this paper. Will try to address this in a future post.]
So of note, the subjects were reported to consume ~1500 cal/day for the 12 weeks of their respective diets. We are told:
Dietary saturated fat and cholesterol intake were signiﬁcantly higher during the VLCKD than the LFD. The LFD led to improvements in some metabolic markers, but subjects following the VLCKD had consistently greater weight loss, decreased adiposity, improved glycemic control and insulin sensitivity and more favorable TAG, HDL-C and total cholesterol/HDL-C ratio responses. In addition to these markers for MetS, the VLCKD subjects showed more favorable responses in alternative indicators of atherogenic dyslipidemia and cardiovascular risk: postprandial lipemia, apo B, apo A-1, the apo B/Apo A-1 ratio, LDL particle distribution and postabsorptive and postprandial vascular function. Most striking, we reported that despite a threefold higher intake of dietary saturated fat during the VLCKD compared to the LFD, circulating saturated fatty acids in TAG and CE were significantly decreased, as was 16:1n-7, an endogenous marker of lipogenesis. There were profound changes, as well, in other fatty acids in circulating TG, PL, and CE fractions (Tables 2–4).
Unfortunately, the VLCKD group averaged an approximately 850 cal/day deficit vs. baseline, while the LFD group only averaged around 600 cal/day deficit. Whatever these other markers were or how favorable or unfavorable they might be, the results are irreparably confounded by the differing caloric deficits and resulting weight loss differential. I'll discuss the full results vis a vis fatty acids in my post addressing the findings of the current study, but wish to make a few observations:
- They didn't alter total absolute (grams) fat intake or absolute saturated fat intake in the VLCKD in this study. Intake was roughly equivalent to baseline at around 100g total, 35g sat fat (note: some numbers not adding up on table).
- The LF group reduced absolute carb intake by almost 60 g/day (roughly 20% of baseline intake of ~270 g/day)
- It had long been established that DNL was not a major pathway and that any significant increases in this required high carb load and/or overfeeding calories. See here and here.
However, the results here for palmitoleic acid would work out as follows:
VLCKD Before: 2.11 g/L total trig x 5L x 4.53% = 478 mg , VLCKD After: 1.04 g/L total x 5L x 3.10% = 161 mg , VLCKD Reduction = 0.317 grams of palmitoleic acid
LFD Before: 1.87 g/L total trig x 5L x 4.54% = 424 mg , LFD After: 1.51 g/L total x 5L x 4.53% = 342 mg , LFD Reduction = 0.082 grams of palmitoleic acid
2010: Limited Effect of Dietary Saturated Fat on Plasma Saturated Fat in the Context of a Low Carbohydrate Diet
Authors: Cassandra E. Forsythe, Stephen D. Phinney, Richard D. Feinman, Brittanie M. Volk, Daniel Freidenreich, Erin Quann, Kevin Ballard, Michael J. Puglisi, Carl M. Maresh, William J. Kraemer, Douglas M. Bibus, Maria Luz Fernandez, Jeff S. Volek (italics indicate author of current study)
Funding: American Egg Board-Egg Nutrition Center Dissertation Fellowship in Nutrition Award.
In this study, they did a randomized cross-over study of 6 weeks duration for either a high sat fat low carb diet (CRD-SFA), or a high unsat fat low carb diet (CRD-UFA). The subjects were 8 weight stable men. The six week time frame was based on assertions that this was the time frame for lipids to stabilize in response to fish oil/omega 3, but whatever .... For the three weeks before each 6-week intervention, the "run-in" (or "washout") was a "standard" low carb diet "using standardized procedures from [their] laboratory": 10% carb, 65% fat, 25% protein. The diets interventions worked out to 12-13% carb, 58-59% fat, 29-30% protein. I would note that the baseline data reported in this study was a little over 2000 calories of 34% carb, 41% fat, 25% protein.
Nutrient intake estimated at baseline from dietary records showed a lower than expected energy, 2,072 kcal/d compared to 2,513 kcal/d for the feeding periods. This was likely due to under-reporting at baseline (Table 1)  although it has been argued that the demands of gluconeogenesis and other processes require more energy for weight maintenance . Habitual carbohydrate intake was also lower than the average American diet at 32%en reﬂecting two subjects who were habitually consuming a lower-carbohydrate diet
So with a small sample size to begin with, they included two subjects who were chronic low carbers? Odd. Again, I'll address the other lipids, etc. in a separate post, but at weight stable caloric intake, both CRD's lowered fasting triglycerides roughly 40 points from the baseline average of 122 mg/dL. Of course (what else is new) we cannot compare these results directly with current reports because the fatty acid profiles are of nanomol/mL units instead of weight percent. Longer chain fatty acids would represent a higher weight percent per micromolar (nanomol per 0.001L = 10^-6 molar) concentration.
So they gave us the concentrations of palmitoleic under baseline, CRD-SFA and CRD-UFA conditions. These were 147.4, 55.9, and 58.4 micromolar respectively. This means that there was a range of 280 to 740 micromoles of palmitoleic acid in the blood stream of these 8 men throughout the study. So less than one millimole = less than a one-thousandth of a mole which works out to about one-quarter of a gram maximum.
The OSU Press Release ...
I'm going to C&P these numbers into the short DNL post I did with the numbers on the current study. But it should be abundantly clear that this quote from Volek is wildly misleading and inaccurate:
If you burn saturated fat preferentially, then how come saturated fats make up around 30% of recycled fats?? The overwhelming source of triglycerides secreted by the liver in the fasted state is excess NEFA released from adipose tissue with some contribution likely due to chylomicron (dietary fat). This is just nonsense.
The Journal ...
Perhaps the editors at Lipids finally got the memo on these studies and took a pass on this third installment answering the question on absolutely nobody's mind. Rather, here's what they sought fit to publish in their most recent issue (the Look Inside links go to an image of the first page for those interested):
- Original Article: Hydroxyoctadecadienoic Acids Regulate Apoptosis in Human THP-1 Cells in a PPARγ-Dependent Manner Venkat N. Vangaveti, Venkatesh M. Shashidhar, Catherine Rush, Usman H. Malabu…Pages 1181-1192 Look Inside Get Access
- Original Article: Alpha-Lipoic Acid Supplementation Reduces mTORC1 Signaling in Skeletal Muscle from High Fat Fed, Obese Zucker Rats Zhuyun Li, Cory M. Dungan, Bradley Carrier, Todd C. Rideout, David L. Williamson Pages 1193-1201 Look Inside Get Access
- Original Article: Inducing Effect of Clofibric Acid on Stearoyl-CoA Desaturase in Intestinal Mucosa of Rats Tohru Yamazaki, Makiko Kadokura, Yuki Mutoh, Takeshi Sakamoto, Mari Okazaki…Pages 1203-1214 Look Inside Get Access
- Original Article: Vitamin E Conditionally Inhibits Atherosclerosis in ApoEKnockout Mice by Anti-oxidation and Regulation of Vasculature Gene Expressions Futian Tang, Meili Lu, Suping Zhang, Meng Mei, Tieqiao Wang, Peiqing Liu…Pages 1215-1223 Look Inside Get Access
- High Density Lipoprotein Level is Negatively Associated With the Increase of Oxidized Low Density Lipoprotein Lipids After a Fatty Meal Sanna Tiainen, Markku Ahotupa, Petteri Ylinen, Tommi Vasankari Pages 1225-1232 Look Inside Get Access
- Original Article: Effect of Compounds Affecting ABCA1 Expression and CETP Activity on the HDL Pathway Involved in Intestinal Absorption of Lutein and Zeaxanthin Eric J. Niesor, Evelyne Chaput, Jean-Luc Mary, Andreas Staempfli, Andreas Topp…Pages 1233-1243 Look Inside Get Access
- Communication: Treatment of Low HDL-C Subjects with the CETP Modulator Dalcetrapib Increases Plasma Campesterol Only in Those Without ABCA1 and/or ApoA1 Mutations Eric J. Niesor, David Kallend, Darren Bentley, John J. P. Kastelein…Pages 1245-1249 Look Inside Get Access
- Methods: Separation of Enantiomeric Triacylglycerols by Chiral-Phase HPLC Tomáš Řezanka, Karel Sigler Pages 1251-1260 Look Inside Get Access
- Methods: Separation and Detection of Plasmalogen in Marine Invertebrates by High-Performance Liquid Chromatography with Evaporative Light-Scattering Detection Shinji Yamashita, Akihiro Abe, Kiyotaka Nakagawa, Mikio Kinoshita, Teruo Miyazawa Pages 1261-1273 Look Inside
Coverage Deluge ...
Which brings me back to the press coverage of this lackluster, would-be obscure article published in a pay-to-play journal. It was splashed everywhere, copying the same quotes from Volek, and totally misrepresenting anything meaningful gained from the study (which wasn't much).
I usually don't think all that much about industry funding per se -- it shouldn't influence things -- and in many cases it doesn't. The data are what they are after all. And yet it does, which is where study design and interpretation come in. Don't get me wrong, we've seen this with research by those advocating other dietary philosophies as well. It should always be considered and viewed with skepticism. When industries like Big Bovine, Large Leche and Enormo Egg get behind the research of a clearly ideologically driven researcher such as Volek, it's plain as day what is going on. Is it any wonder that The Big Fat Surprise got all the buzz it did? Nina Teicholz's case in that book -- the vaunted supreme science -- hinged on Atkins and meat/dairy/egg funded research by The New Atkins trio: Westman, Volek and Phinney. Oh ... and not to mention Richard "Entropy & Mirrors" Feinman among the authors of the first two studies.
It's shameful really, that nobody in the mainstream media can even look up from their coffee and smell the ketotic stench. Speaking of that (coffee) ... with WARNING regarding profanity, and w/o specific endorsement (also, Harley needs to learn about gluconeogenesis!) -- aaaaannnnd veering somewhat off topic -- I bring you Durian Rider discussing the recent ABC Catalyst program:
Oh ... and in case you don't follow me on Twitter or FB ... Look who bumped into the big Kahuna of low carbers himself recently!!
|Top two: Early July 2012 2nd month of Nutritional Ketosis|
Bottom: November 2014 2.5 years of NuttyK
Forgive me please. If I didn't get little chuckle over this nonsense every now and then, I'd probably cry!!