USA Today on JAMA "Metabolic Advantage" Intervention Study

A study was published in JAMA that addressed the effectiveness of a variety of diets for weight loss maintenance.  The question was:  we know that folks can demonstrate a reduction in metabolic rate after weight loss that makes it more likely for them to regain weight; which diet minimizes this effect?  The study wasn't large, but it was an intervention study and the technology utilized for measuring the results was relatively uncommon in these types of studies and significant.  The answer was clear:  carb restriction worked best.

I think the fact that this study was done might be attributable to Gary Taubes' work, as it appears to be designed to test the hypothesis he re-discoverd and advocated in his books, "Good Calories Bad Calories" and "Why We Get Fat" (available in my aStore, by the way).

When I see a study published like this one, I get excited.  This one will draw comments from all of my favorite carb restriction bloggers.  This one is a shot in the face of the "calorie is a calorie" reductionists (who are correct and all wrong; correct about the physics and incorrect in their linear application of it to a human body as if it was a bomb calorimeter).  There will be some interesting attempts from the "C is a C" crowd to explain this one away.  Squirming and hemming and hawing will ensue as they try to deal with a cognitive dissonance they will be unable to reconcile.

What was the study?
The research finds that dieters who were trying to maintain their weight loss burned significantly more calories eating a low-carb diet than they did eating a low-fat diet.  But some experts say these findings are very preliminary.  The study, funded by the National Institutes of Health, was designed to see if changing the type of diet people consumed helped with weight maintenance because dieters often regain lost weight.  So scientists had 21 obese participants, ages 18 to 40, lose 10% to 15% of their initial body weight (about 30 pounds). After their weight had stabilized, each participant followed one of three different diets for four weeks. Participants were fed food that was prepared for them by diet experts. The dieters were admitted to the hospital four times for medical and metabolic testing.
http://www.usatoday.com/news/health/story/2012-06-27/calories-low-carb-weight-loss/55843134/1

I love this "reporter speak":  Some experts say the results are very preliminary.

Can study results be "very preliminary?"  That phrase makes me chuckle as I remember a high school teacher who directed that I "completely eliminate redundancy" and then lined through the word "completely."  Point taken.

And if they are "very preliminary" what does that mean anyway?  Was it a well done study or not?  If it is, what sense do you make of the study, Mr. Expert?  Those would have been some of the good questions to ask, but ones not asked so much by the "newspaper blah blahs" I suppose.

Here's the link to the JAMA report:
http://jama.jamanetwork.com/article.aspx?articleid=1199154

So why do I feel so smug about the result?  Why would I indulge in the "I told you so" routine to those who represent what I think of as 40+ years of bad science?  Mainly because their work has hurt people.  They have advanced the low fat message like an item of religious faith in spite of the lack of science to support it, while claiming they were speaking with scientific authority.  They projected their strongly held beliefs, and pretended it was a fact.  In short, they did what all humans do, but they did what they did from positions of power and authority, and their discipline was unequal to their power to influence.  I'm not saying "They lied, people died."  I don't mean to imply they deliberately deceived anyone.  They deceived themselves and didn't have the discipline to just say "This is what I think but it's not proved yet."  What they did is something to be angry about.

You can safely predict there won't be too many from the "calorie is a calorie" crowd who say "well, I guess I was wrong about low carb, sorry."  Not too many will say "Gee, I guess that Taubes guy isn't a money grubbing buffoon after all."  None will apologize to Dr. Atkins or the Eades or Loren Cordain.  In other words, there will be very few who swallow their pride and admit this one is a direct contradiction of what they thought they knew.

Here's the "titular head" of the "calorie is a calorie" crowd, cited as an "expert", to whom we are supposed to pay attention:

George Bray, an obesity researcher at Pennington Biomedical Research Center in Baton Rouge who has also studied this topic and who wrote the accompanying editorial in JAMA, says that other studies "show that you can do well on any diet as long as you stick to it. Adherence is the major key for weight loss and maintenance. There is no magic in any diet."

This is the same guy that has said diets don't work due to the toxic food environment and there's really no hope short of pharmaceuticals.  He's also ignoring the fact that low fat diets are hard to stick to because of the resulting hunger.  And he's pretending not to notice all the research that shows exactly what this JAMA study shows - low fat dieters who lose weight commonly suffer a reduced rate of metabolic activity (this was a featured component of the recent NYT article which said, essentially, "there's no hope for long term weight loss because the body compensates for weight loss by reduced metabolic rate").  And this is also a guy from the camp that has said that we all need to just walk or move enough to  burn 50 kcal/day or so to use up the extra "energy" we all tend to consume - now after a study that shows a 300kcal/day metabolic advantage, all he has to say is (to be fair, all he's reported to have said) "diets are great, just follow one".  From my completely inconsequential perspective, Dr. Brey's long career and his significance as a researcher has been to advocate a linear relationship, uncomplicated by hormonal and individual variances, between food intake and energy expenditure and weight gain/loss.  So, I wouldn't expect him to be confused by the facts since what the facts of this study say are "you were wrong". 

Eric Westman, a Duke University researcher who has conducted several studies on the low-carb diet and is co-author of The New Atkins for a New You, says this study documents that the "lower the carbohydrates, the better the metabolic effects. People burn more calories if they eat fewer carbohydrates."

What he should have said was "I told you so."

Marion Nestle, a nutrition professor at New York University, says longer studies conducted among people in their own environments, not with such controlled meals, have shown "little difference in weight loss and maintenance between one kind of diet and another." More research is needed to show that interesting results like these are applicable in real life, she says.  "In the meantime, if you want to lose weight, eat less." (emphais mine)

Part of what she says is a BFO - no one study is compelling in science, and oh by the way, things are different in the real world than for those eating prepared foods during a controlled experiment.  Gee, thanks for the insight.  Thanks also for the smug advice at the end, too, Professor N, that provides us all the information we need to know about the obesity/health care crisis in the US.  Message from Professor N to anyone that is overweight - "You are fat because you are gluttonous and lazy, get off your butt and starve yourself.  Your bad character is wrecking our health care system, knock it off."  Does she think that repeating that message for another 30 years is going to work better than it has for the last 30 years?  These people are a joke except there's no punch line - there's a nation of sick people and much of the dietary confusion of the last 30 years could be blamed on folks like Professor N and Dr. Brey. 

Or you could skip the blame and just accept the pathetic low fat pseudo science of the last 30-40 years and get over it, which I will endeavor to do after this article is complete.

In ten years, the blah blahs at the newspapers, however, will be writing about this study and more that will follow as if the superiority of a carb restricted diet has always been a well known fact.

Here's a blurb for those wary of the sin of epidemiology (which is to say confusing correlation with causation):

The authors note a downside to the low-carb diet: It appears to raise some risk factors for heart disease.

This is the high fat bias on display.  The article author - a newspaper blah blah for sure - had to find something bad to say about a study which shows a stunning finding in favor of high fat diets.

So, what does the study say about how high fat diets will kill you faster than drinking 16.1 ounce sodas in New York City?  "Risk factors" is the epidiological language for "factors which correlate to disease that we would like to think we know are causative." 

But for actually predicting heart disease, for example, the best numbers available are either:
-Ratio of LDL to total cholesterol (what my insurance company uses to figure out how soon I'll die)
-Ratio of triglycerides to HDL

Interesting results for study participants:
*Serum leptin was highest with the low-fat diet (mean [95% CI], 14.9 [12.1-18.4] ng/mL), intermediate with the low–glycemic index diet (12.7 [10.3-15.6] ng/mL), and lowest with the very low-carbohydrate diet (11.2 [9.1-13.8] ng/mL; overall P < .001) (Table 3)
In other words, leptin levels are higher with a high carb/lowfat diet, which is known to result in increased hunger and decreased metabolic output - leptin resistance anyone?

*Regarding components of the metabolic syndrome, indexes of peripheral (P = .02) and hepatic (P = .03) insulin sensitivity were lowest with the low-fat diet. Comparing the low-fat, low–glycemic index, and very low-carbohydrate diets, serum HDL cholesterol (mean [95% CI], 40 [35-45] mg/dL; 45 [41-50] mg/dL; and 48 [44-53] mg/dL, respectively; overall P < .001), triglycerides (107 [87-131] mg/dL; 87 [71-106] mg/dL; and 66 [54-81] mg/dL, respectively; overall P < .001)
In other words, low carb is great for HDL and triglycerides (already known, so essentially these stats validate the test protocol)

*CRP tended to be higher with the very low-carbohydrate diet (median [95% CI], 0.78 [0.38-1.92] mg/L for low-fat diet; 0.76 [0.50-2.20] mg/L for low–glycemic index diet; and 0.87 [0.57-2.69] mg/L for very low-carbohydrate diet; P for trend by glycemic load = .05). Blood pressure did not differ among the 3 diets.
This is not a good indicator, but the significance of CRP compared to the other markers, which are more positive, is not known.

The study conclusion:
The results of our study challenge the notion that a calorie is a calorie from a metabolic perspective.

Hell yes they do!  Eat meat, vegetables, eggs, nuts and seeds, little fruit or starch, and no sugar/wheat.

(Minor edits June 27, 2012, 16.44)