So there's a new series of YouTube videos available of yet another Taubes lecture. I haven't had the time (nor stomach) to listen to it all yet, but what caught my eye (or ear) was his invoking of the Shai study. He does so first towards the end of his formal "tele lecture".
FF to ~ the 6:30 mark in THIS VIDEO where Taubes discusses the weight loss and caloric intake that supposedly supports his theories.
Just to remind you, here is the weight loss graphic for 2 years on the 3 diets:
As you can see, yes, the LC group did sustain statistically significantly more weight after 2 years than the low fat diet, but as you can also see, there is an insignificant difference between LC and Mediterranean (I'll use MDTN) diet compared to LC after about the 1 yr. mark.
Now Taubes does his typical (intentional?) misrepresentation by implication of calorie restriction. He notes that both LF and MDTN are CRD's, while LC is not restricted calories. As I've noted before ad libitum does NOT mean eating more calories or eating to your heart's content and then some. Taubes even goes so far as to state "you can't eat carbs, you can basically exercise as much gluttony as you want as long you're eating fat and protein"
GOT THAT? The next time anyone tells you that Taube$ has never claimed you can eat all the fat and protein you want without gaining and/or perhaps losing, link to this video. He implies that the LC group ate the same or more calories and certainly implied that you can be a fat & protein glutton. Yep ... that's what some want to hear. The magic bullet. *SIGH* If only it were true.
So anyway, after listening to this, I was left to assume that Taubes simply looked at the weight loss graphic, presumed the LC group consumed more calories than the LF group and didn't bother to look at the "evidence" fully. By that I mean, the evidence he acknowledges is missing from Foster (that new low carb v. low fat study where actual dietary intakes were not reported) was reported in far greater detail in Shai.
You can see the full table at my link, but here's a condensed one (I excised the %'s carb/fat/protein as these have limited meaning for comparison when total caloric intake varies).
Contrary to his assertions, the group that achieved comparable (average) weight loss while consuming more calories was the MDTN group! Their mean restriction was roughly half - 3/4 (depending on time point) that of the LC and (surprisingly) the LF groups. Indeed the caloric restriction was comparable between the LC and LF groups. Now Taubes goes on to do his condescending number of "if I had an 8th grade education" (please spare us) that this refutes calorie balance theory. But does it? I don't think so. LOOK at those +/- numbers!!!!! We're talking almost 1800 calories for the LF group at 6 months. But more striking is that the MDTN group's +/- numbers are consistently smaller -- about half that of LF & LC. What does this tell me? Absent raw data, nobody can know for sure. But this SIGNIFICANTLY different variability in the outcomes indicates a greater consistency/compliance with the more moderate MDTN diet than either of the extremes. It is also important to understand that the standard deviation (SD, which is what the +/- values are) can be heavily influenced by outliers and offers no indication as to the distribution of the outliers. This supposed contradiction to calorie theory -- comparing just LF and LC, groups with comparable caloric restriction -- could be explained by LF outliers being those who couldn't adhere to the diet and consumed more and the LC outliers being those (like me, for instance) who dramatically (spontaneously) cut calories and experienced weight losses WAY more than any of the means reported in this study. I can't know this, but there's no reason to throw out the thousands of studies where caloric needs have been individually assessed and humans have either maintained or lost weight predictably when caloric intake has been controlled to obtain the desired result based on this study, that's for sure!!! And it is also important to note that, the mean is a parameter that can be greatly influenced by outliers. It wouldn't take many 30-50-80 lb weight losses to shift a mean several pounds, which is all we're really talking about here anyway.
Giving him the benefit of the doubt he no longer deserves, I presumed that Taubes was being intellectually lazy, not deliberately deceitful. IOW, he hadn't taken the time to read all of the results and scrutinize the "evidence". I was (yet again) proven wrong. I listened on ..... (Part 8 of 8 seems to be cut off at the end, so there's a bit missing, but the "formal lecture" continues in the "Bonus coverage" video).
You can pretty much listen from the beginning of the next video HERE. Surprise, surprise! Taubes DID look at the table of intakes after all!! Basically he says that whatever the small losses achieved by the LF group, it was ultimately due to the fact that they, too, restricted carbs! That's right. Expecting his audience to develop a blind spot for the right hand column (where those without bias induced vision impairment can see that the LC group DID in fact restrict calories, if not purposefully), Taubes puts the graphic on a slide in all its glory. He focuses on the fact that of the about 60% of the caloric restriction in the LF group (at 2 years) can be attributed to an approximately 80g reduction in carbs. So Taube$ concludes that the carb restriction is responsible for the weight loss. If one compares just the LF and LC columns, they might buy into this deception.
But ...
Gary, Mr. Taubes, however you prefer to be addressed. Do YOU have a blind spot down the center of your field of vision???? There's a center column on that table that you've ignored, and in doing so you you've shot yourself in the foot. Comparing the MDTN to the LC or LF groups, and applying the very same benchmarks from which you drew your conclusions we find that:
1. MDTN restricted calories to a lesser degree than LC and
2. MDTN restricted carbs to a lesser degree than LF and a far lesser degree than LC
And yet .... ta da!!! They lost the same amount of weight on average as the LC group and more than the LF group. To repeat: MDTN restricted BOTH carbs and calories significantly less than the LF group, but lost more weight. They also restricted the calories similarly less and carbs much much less compared to the LC group, and lost the same amount of weight. (They also didn't have an extended period of weight regain, their trajectory looks far more optimal). If I had a 2nd grade education ... (sorry, couldn't resist the sarcasm) ...
I'm not done.
Taubes apparently also has a blind spot down the right side of his field of vision that prevented him from critically reviewing just the LC results. Before I go into this ... it bears repeating the date of Shai's study: July 2008. OK, not in time for GCBC, but certainly predating innumerable $peaking engagement$.
Notice anything?? Supposedly, the LC group FURTHER restricted BOTH calories AND carbs between 6 months and 12 months (OK, not by much, and admittedly not statistically significantly, but work with me here :) ). What did this coincide with on the weight loss graphic? Weight GAIN.
Also note that the LC group even reduced absolute fat intake (albeit to a very modest degree and with huge variation about the mean).
To be fair, averages obscure actual results. Perhaps a weight differential/caloric intake ratio for each individual would be a better measure. BUT, we need to be consistent.
Bottom line, Taubes is full of Shai-t! This "evidence" is flimsy at best.
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