Tag Archives: energy balance

Look AHEAD – Nutrition Disinformation 2.0

The day you’ve all been waiting for has finally arrived.  Results from the Look AHEAD study have been published.  When I first wrote about this study (HERE), it had been prematurely halted because the intervention was providing no benefits.  Everybody was in a state of shock and awe because Low Fat didn’t save lives.  But that was before we even had the data.  

Reminder: the “intensive lifestyle intervention” consisted of a Low Fat Diet & exercise.  The results?  Yes, they lost more weight than control, but they also took more Orlistat (of which I’m not a fan, see HERE for why):

orlistat

Orlistat = pharmaceutically enhanced low fat diet. 

Their normal diets were not healthy, but neither was low fat –>

med use

Medication use increased drastically in both groups.  The pundits have gone wild because medication use was lower in the intensive Low Fat group at the end of the study, but this is Nutrition Disinformation 2.0.  Eerily reminiscent of the recent Mediterranean Diet study, the conclusions are the same: keep eating poorly and the need for medications will increase.  You can call it a lot of things, but not “healthy.”  The alternative –>  How to define a “healthy” diet.  Period.


Significant adverse events:SAE

The only thing to reach statistical significance was more fractures in the intensive Low Fat group, but you didn’t read any headlines that said “Low Fat breaks bones.”  Imagine if that happened on low carb [sigh]  The next closest thing to statistical significance was increased amputations in the intensive Low Fat group :/

gem:History of CVD

Translation: if you were healthy at baseline, then you could tolerate a low fat diet.  Otherwise, not so much.  This is exactly what happened in the Women’s Health Initiative.

Ha

needless to say, none of the “possible explanations” they considered were Low fat diet Fail.

calories proper

Eating in the Absence of Hunger

Hat tip to Jane Plain and her ongoing series on “The physiology of body fat regulation” for citing this study as it provides a rather interesting insight into the psychoendoneuropathophysiology of the obese condition.  Eating in the Absence of Hunger.  

Caloric compensation and eating in the absence of hunger in 5- to 12-y-old weight-discordant siblings (Kral et al., 2012)

They were all full or half, weight-discordant, same-sex siblings and each sibling pair had the same mother; same mitochondrial DNA, shared a womb, etc.

Continue reading

Are carbs stored as fat?

Hint: “no”

DNL proper.

Lots of metabolism talk below, but first a brief intro.  My “muse,” if you will.

Taubes’ recent article in the BMJ (Taubes, 2013full text) generated some interesting feedback.

In the original article, Taubes basically re-states his philosophy on obesity.  Nothing new.  But one rebuttal by Cottrell got under my skin (Cottrell, 2013), and Taubes’ response was woefully inadequate.

Cottrell [sic]: “A third incorrect assertion is that obesity can be attributed to the conversion of carbohydrate to fat. This is an unsatisfactory explanation of obesity, because this route is a minor pathway to depot fat in humans, even under conditions of substantial overfeeding of sugars to obese subjects.  An unproved assumption is that the hypothetical diversion of carbohydrate energy into fat storage leaves the subject hungry, thus stimulating overeating.”

strawman

Cottrell set up a straw man and handily took it down.  The primary mechanism whereby excess carbs contribute to obesity is via insulin’s effects on adipose tissue.  Even if you’re eating very little fat, insulin will cause it to get stored.  Insulin is very good at this – it is actually far more potent at stimulating fat storage than it is at stimulating glucose uptake (eg, Insulin vs. fat metabolism FTW).  Cottrell’s straw man is that excess carbs themselves are stored as fat.  This does not occur to any appreciable extent in humans.  Here is why I believe that to be true, from one of most insightful and informative studies on the topic IMHO.

Continue reading

Brown adipose tissue

Once thought to be the holy grail of energy expenditure manipulators and a potential cure for obesity – fail.  I don’t have great evidence for this; it’s really just a hunch.

A new mouse study has provided some additional fodder for speculation, however.

The theory & background info: increased BAT activity can effortlessly burn away excess fat mass by using fuel to create heat instead of energy.  This model was most aptly summarized by the title of Dr. Efraim Racker’s 1963 ediorial: “Calories Don’t Count-If You Don’t Use Them.”  At best, I don’t think BAT is a panacea.  At worst, we might’ve learned our lesson long ago from DNP (circa 1938; also McFee et al., 2004; Miranda et al., 2006; Tewari et al., 2009; and Grundlingh et al., 2011).

drug banned

In a slurry of publications in 2009, researchers re-ignited the quest by showing cold-induced BAT activation in healthy humans (Virtanen et al., 2009):Virtanen BAT

Continue reading

Liver is evil but need not be punished. SFAs.

What to serve with a liquid lunch, and a recipe for chocolate.

It’s like a feed forward downward spiral.  If you don’t eat saturated fat & MCTs prior to imbibing, then liver intentionally makes more PUFAs for the alcohol-induced burning ROS to molest.  Liver is evil but need not be punished.  SFAs.

Brief background: (Kirpich et al., 2011 & 2013)

Researchers studying alcohol in rodents know where they’re going and like to get there fast.  70 drinks per day fast.  Granted, rats metabolize faster than humans so it’s likely a little less… but a little less than 70 is still a lot of sauce.

Continue reading

Obesity is not permanent

Take a group of obese people (> 250 lbs) and put them on a massive calorie restricted diet.  They lose weight and metabolic rate plummets.  Weight loss fail?  In most cases, yes.  But a recent study showed that the decrepit post-weight loss metabolic rate gradually improves in parallel with an increase in dietary fat ingestion to such a degree that even after two long years: totally food intake was almost back to normal, energy expenditure improved, and all this happened despite continual weight loss.  In other words, obesity is not permanent. 

creme brulee

Decreased energy density and changes in food selection following Roux-en-Y gastric bypass (Laurenius et al., 2013)

Statistically speaking, no diet on Earth comes close to RYGB in terms of weight loss success.  Long term.  Seemingly permanent.  It’s the closest thing to a cure we’ve got.

Laurenius

Body weight is down by 30%, and energy expenditure is rising faster than a speeding bullet.  because food intake is increasing while body weight is dropping – they’re probably more active too ** weight loss than more exercise –

But there’s a more mystical aspect to RYGB that warrants attention.  (it could be the increasing fat intake, but for now let’s just say it’s RYGB per se).  According to this pearl, weight loss of only 10% via diet alone causes energy expenditure crash by 394-500 kcal/d, and physiological replacement of leptin via subcutaneous injection can increase this by 234-454 kcal/d (Rosenbaum, Murphy, Heymsfield, Matthews, and Leibel, 2002).

Continue reading

How to define a “healthy” diet. Period.

Whether you’re strictly adhering to a diet or just doing your own thing, if year after year your GP is prescribing more and more medications to stave off morbidity and keep you intact, then the diet you’re following is most likely Fail.  The same is true if your body weight is creeping upward or your quality of life is creeping downward.lunchables

The glaring Fail of all 3 diets in the recent Mediterranean Diet Study for the medications criteria threw up a huge red flag.  As a brief refresher, at baseline and 5 years later, prescription medication usage was as follows:

Continue reading

Mediterranean Diet Fail – Nutrition Disinformation, Part I.

Do not get your hopes up, do not pass GO!  do not collect $200.  The Mediterranean Diet.  Fail.

Primary Prevention of Cardiovascular Disease with a Mediterranean Diet (Estruch et al., 2013)

This is one of the biggest diet studies we’ve seen in a while, and no doubt it was a very good one.  It very effectively put the Mediterranean Diet to the test.

I felt compelled to write about this study out of fear for the nutrition disinformation that it would likely inspire.  The Mediterranean Diet is associated with all good things, happiness, red wine and olive oil; whereas the Atkins Diet is associated with artery clogging bacon-wrapped hot dogs and a fat guy who died of a heart attack.  Nutrition disinformation.

If you ran a diet study with 3 intervention groups for 5 years, and by the end of the study everybody (in all 3 groups) was on more prescription medications, would you conclude any of the diets were “healthy?”  If so, then we should work on your definition of “healthy.”

Study details: big study, lasted roughly 5 years, and the diet intervention was pristine.  Mediterranean diet plus extra virgin olive oil (EVOO) vs. Mediterranean diet plus nuts vs. low fat control.  They even used biomarkers to confirm olive oil and nut intake (hydroxytyrosol and linoleate, respectively).  Compliance was good.

Continue reading

Fat mitochondria

No, not heavyweight powerhouses.  Mitochondria IN fat cells.
electricity is required for your space heater, not your long johns.

mito

At first glance, the mere presence of mitochondria in adipocytes seems perplexing.  On one hand, there’s tons of fat to burn, so why not have the capacity to do it?  Well yeah, but on the other hand, adipose doesn’t do very much.  It doesn’t contract like skeletal muscle or crank out glucose like liver.  Mitochondria in BAT is understandable, to generate heat and what not.  electricity is required for your space heater, not your long johns.

My best guess is that adipose tissue mitochondria are there to do something else – make shorter acyl chained FA’s, or free radicals, etc., to signal something.  Just not primarily to generate energy.

But drop an anvil on adipose tissue mitochondria and you get some interesting mice indeed.  Impossible mice.

TFAM – in brief, the enzyme that goes by the acronym TFAM makes mitochondria work.  Global TFAM KO is lethal.  But adipose tissue (AT)-specific KO is interesting.  Uncoupling goes through the roof and fat literally burns away.  kind of***.

Adipose-specific deletion of TFAM increases mitochondrial oxidation and protects mice against obesity and insulin resistance (Vernochet et al., 2012)

Continue reading

Ketoadaptation

Athletes who drop carbs cold turkey suddenly suck.  It is known.  

But with a smidge of stick-to-it-iveness, performance completely recovers, in virtually every.  measurable.  aspect.  

This was shown years and years ago, in a seminal study by Drs Phinney, Bistrian, Evans, Gervino, and Blackburn.

The human metabolic response to chronic ketosis without caloric restriction: preservation of submaximal exercise capability with reduced carbohydrate oxidation (1983)

Normally, fatty acids fuel low intensity exercise and carbs fuel high.  This is because high intensity exercise requires a high rate of ATP production, and glycogen to lactate generates ATP faster than a speeding bullet.  This is what makes power.  Getting ATP from fatty acids is like draining maple syrup from trees [at first].

mito pic

However, go low carb for long enough and the syrup begins to flow like water.  I lack the time to show what “long enough” entails, but  4 out of 5 studies on low carb diets and performance that only last a few days will show this.  Ketoadaptation takes time; ~3 weeks.

Continue reading