Lean Times

While John Cloud erred in several ways in his Time magazine article titled Why Exercise Won’t Make You Thin, he's correct on the fat loss issue. Many people including the Surgeon General have lambasted Mr. Cloud for his candor and scientifically sound information on getting svelte.

 What he was saying is that exercise does not affect fat loss much if at all. And research on the subject of exercise and fat loss supports his statement time and time again. Even the American College of Sports Medicine agrees that exercise does little to affect it as we’ll learn shortly.

 The knee-jerk reactions that bombarded the internet lambasting Cloud for the article which include Jake Steinfeld (the Jake of  Body by Jake Fame) only serve to keep people fat and injured.  They assume that Cloud is saying that exercise is not good for us or that it provides no benefit. That is not what John Cloud was saying. And he does, in fact, make mention of the many benefits of exercise. In fact he even says at the end of the article “You should exercise to improve your health…” Again, the title of the article is "Why Exercise Won't Make You Thin." And it won't. It never has and that is a fact of science. Good for John for having the guts to reveal this information and help us all get closer to the truth and, perhaps, save us from an orthopedic injury.

 Jake Steinfield, who may I say I respect and admire, had this to say on his Huffington Post blog:

 “Cloud states that the American College of Sports Medicine and the American Heart Association's guidelines regarding weight loss and exercise are unrealistic, especially for those with jobs or those looking for jobs. The guidelines encourage exercise for 60 to 90 minutes on most days of the week. What he fails to mention is that they also say that "research shows that moderate-intensity physical activity can be accumulated throughout the day in 10-minute bouts, which can be just as effective as exercising for 30 minutes straight. This can be useful when trying to fit physical activity into a busy schedule."

 What Jake neglects to mention is that, unfortunately for those who seek to lose weight via exercise, the ACSM admits exercise doesn’t work. From the AHA/ ACSM paper titled: Physical Activity and Public Health. Updated Recommendation for Adults From the American College of Sports Medicine and the American Heart Association (page 7):

 “It is reasonable to assume that persons with relatively high daily energy expenditures would be less likely to gain weight over time, compared with those who have low energy expenditures. So far, data to support this hypothesis are not particularly compelling.”

 Also from Jake’s Huff Post blog (he is quoting Dr. Robert Sallis, past president of the American College of Sports Medicine): 

"If exercise were a pharmaceutical it would be the most potent drug ever invented. Exercise has been clearly proven to prevent and treat chronic diseases and lower mortality rates. From a scientific perspective, any attempt to discredit the value of exercise is just laughable and potentially very harmful to the public. As a physician who works hard to get patients more active, I find it very irresponsible for Time magazine to run a story that so misrepresents the facts."

Well, Dr. Sallis isn’t quite correct. All of the studies done on exercise that are used as iron clad proof that exercise prevents and treats chronic disease and lowers mortality rates are epidemiological / observational studies. These types of studies are not controlled research studies. They can only suggest an association - they do not prove cause and effect. Just because people who exercise regulary live longer and are generally healthier than those who don’t doesn’t mean that the exercise caused these benefits.

But why? Why does exercise have little to no effect on fat loss? There are many reasons including increased appetite and being more sedentary after the workout. An interesting example of this was watching my daughters ride their bikes around Mackinac Island last week while we were on vacation and after the 8 mile ride all they wanted to do was sit in bed and read.

But the most important issue is the understanding of the language of fat loss. What tells the body to release fat from the fat cells?

Fat loss is not a numbers game. In other words, a calorie is not always just a calorie. Fat loss is a hormonal game. Fat is not released from the fat cells because you burn calories doing exercise. No one loses fat without altering their diet and sticking to that alteration. And the specific alteration is a reduction in carbohydrates, not necessarily calories, which in turn reduces insulin secretion, which in turn allows the lipids to be released form the fat cell. That's the biochemistry. We don't get to vote on it. There are other issues, but this is far and away the most critical.

And why do so many experts and the ACSM assume exercise will work even though time and time again research fails to support the assumption. So too do the failures of millions of Americans who try to shed the pounds by sweating to the oldies.

A thorough read of Gary Taubes' book Good Calories Bad Calories explains this in great detail. According to Gary:

"Obesity is a disorder of excess fat accumulation. So the question everyone should be asking and always should have been asking is what factors regulate fat accumulation? As it turns out we've known that since the 1960s and it is not controversial. You can find it in endocrinology and biochemistry textbooks, just not in obesity textbooks. Fat accumulation is fundamentally determined by the hormone insulin and our insulin levels go up and down with the quantity and quality of carbohydrates we consume. The more carbs we eat, the more refined they are and the sweeter they are (the more fructose in them, in other words), the more insulin we will ultimately secrete. The higher our insulin levels, the more fat we accumulate."

Exercise cannot and does not solve the problem of fat release from the fat cell. The real key to the fat cell is not exercise. It is the control of hormonal tone and the most important hormone to control is insulin.

As the late Carl Sagan said: "Science as a candle in the dark."

Comments

[Drew Baye]

In the fifteen plus years I've been training people I've never known anyone to lose a significant amount of fat from exercise alone - only when they modified their diet did they start to lose fat.

Exercising for the sake of burning calories is a huge waste of time. While there are other benefits to be had by exercising, these can be achieved more efficiently, more safely, and to a much greater degree with a program of hard, brief strength training.

[Ken]

Most of us believe what we're fed by marketers - exercise is the key to weight loss. All of my experiences, reading and observations lead me to believe the opposite. Diet for weight control, and exercise for health and well being.

[Brandon Schultz, D.C.]

The deliberate use of the insulin respone post-workout is widely utilized: having a shake or meal containing protein and a small amount of carbohydrate, which will shuttle protein (amino acids) into tissues (muscle) to promote hypertrophy or at least muscle maintenance. There is much debate about this among authors regarding roles of purely protein supplements vs. carb + protein concoctions and the ramifications of each.

What Fred and others are referring to (please correct if I'm mistaken) is the chronically elevated levels of insulin found in people who have maintained an elevated carbohydrate intake over many years and the resulting excessive fat storage. By restricting carbohydrate intake, you teach the body to "relearn" fat mobilization for fuel, not purely for storage.

The argument about calories is VERY complex. Between varying elements such as thyroid hormone activity, insulin sensitivity, activity level and type and many others will effect weight regulation. As a diet for weight loss continues these variables many change, thus altering any "calorie" count and need.

The low carb diet is great for overall health as mentioned by "LC" above and for weight regulation.

In health
Brandon

[fred hahn]

I hear you LC and I agree. Folks like Mike are unaware how stuck they are RE calories. They don't and won't get it or think think deeply enough about it. Ah well.

As for the biggest loser, morbidly obese people can lose more weight/fat than people who just need to lose 20 or 40 pounds. They shed a lot of water and visceral fat (VAT).

I also think they lie and exaggerate. After all, it's TV. I have been in contact with them over the years as one of my clients was/is very influential at NBC. The producer of the show declined to have me on after I challenged her that I could beat the two BL trainers ITO fat loss and improvements in health with contestants by doing a 6th of the exercise and not making any one cry.

The show is not interested in helping people. Just ratings.

[LCforevah]

Fred, as a layperson who's a big fan of the Drs Eades, I completely agree with you and their research that fat loss is strictly hormonal. I can only go from my results and high carb/low fat diets never produced results, only frustration. I add Taubes' book for a complete historical explanation of why high fat/moderate protein works.

Mike, it's not only the weight loss that works with hf/mp, it's the leg pains that disappear, the skin rashes that dissappear, the headaches, the bloating, the irritable bowels--the list is endless. This never happens with high carb--quite the opposite--it exacerbates my psoriasis, my bloating and headaches.

I know I am only an anecdote, but I simply cannot utilize anything but high fat/moderate protein for my continued well-being.

Fred, there is one situation that really frustrates me as a layperson--the Biggest Loser phenomenon. When there are men and women losing over 20-25 pounds some weeks on that program, it's hard to explain to friends why I think my WOE is more important than exercise. I would really appreciate an explanation I can give to people. I think the Big L is so unrealistic and quite a few of the graduates have regained their former weights!

[fred hahn]

"Hi Fred,

I hope you do come back - a dissenting opinion is never a bad thing."

We'll see Mike. The others on that forum thus far have been children. And let's be clear - your is the dissenting opinion. Your opinion or stance is (correct me if I'm wrong):

1. calories count meaning, if you take in more calories than you expend, you store adipose tissue.
2. there is no metabolic advantage to low carb diet
3. Controlling insulin is not THE significant factor in adipose tissue regulation

"In terms of your buddies, I was reffering to those who share your opinions - just so you don't feel overwhelmed. Regina Wilshire is someone I respect very much. Adam Campbell is a member at the forums as is Cassandra Forsythe."

Sure you can invite them. But these folks more than likely will not waste their time on a forum like this one to debate. I think debating Regina is not in your best interest however if you want to 'win.'

"I addressed the A-Z study in my last JP post. When discussing metabolic advantage, metabolic ward studies are the gold standard. It depends on what you are trying to prove. Again, I'm not saying your studies are invalid - just that they don't have the same degree of conrol."

If you are going to smack down my studies that are not ward studies, then every study you cite to support your position must then be a ward study. Otherwise, don't bring then up. There are VERY few well done ward studies. In fact, why not send me the links to the ones you feel are the best 2 that suggest that there is no such thing as a MA and I'll dissect them.

[Mike]

Hi Fred,

I hope you do come back - a dissenting opinion is never a bad thing.

In terms of your buddies, I was reffering to those who share your opinions - just so you don't feel overwhelmed. Regina Wilshire is someone I respect very much. Adam Campbell is a member at the forums as is Cassandra Forsythe.

I addressed the A-Z study in my last JP post. When discussing metabolic advantage, metabolic ward studies are the gold standard. It depends on what you are trying to prove. Again, I'm not saying your studies are invalid - just that they don't have the same degree of conrol.

Hope to see you back.

[fred hahn]

"Fred, to even the playing field - I'll invite some of your friends to help you out on your arguments on the JP forums. I know a few of them and I'm sure I can rustle some of them up.

Hope you will stick around though - you will get a good scientific discussion if you do.

http://forums.jpfitness.com/diet-nutrition-supplementation/39280-fierce-conversations-2-more-important-adequate-protein-carb-reduction.html"

My "buddies?" Like who?

I'll stick around so long as the discussion remains civil, logical, grounded in science and that you in particular stop pretending that I do not put forth research in support of my statements and that you answer my questions when asked. EX: You have you to explain the A to Z diet. And if you are going to use ward studies against me, then ALL of your research used to support your position must also be ward studies. Otherwise, ditch the ward studies as there are very few that have been done on any subject in nutrition.

[Mike]

Fred, to even the playing field - I'll invite some of your friends to help you out on your arguments on the JP forums. I know a few of them and I'm sure I can rustle some of them up.

Hope you will stick around though - you will get a good scientific discussion if you do.

http://forums.jpfitness.com/diet-nutrition-supplementation/39280-fierce-conversations-2-more-important-adequate-protein-carb-reduction.html

[fred hahn]

"James - thank you for clarifying my position - you have the absolute right of it. "Calories matter" is not the same as "a calorie is a calorie".

If I have misinterpreted your meaning, can you explain how the two are separate and distinct. Thanks.

"James' take on insulin reflects my understanding of it - that it is but one factor - not THE factor. Although I'm a little perplexed. In one sentence you say; "Insulin doesn't make us fat" And in the next breath you say; "Increases in insulin via high carbohydrate diets favor fat storage and inhibit fat mobilization" So... how is this different?"

I shouldn't have to explain this to you Mike. Insulin in and of itself does many things. Regulates blood sugar, helps transport AA to cells (anabolism), but one of it's primary jobs is fat storage. Insulin contributes to obesity when levels are high. By keeping insulin levles chronically high, you are telling the body to store macronutrients as fat more readily than when insulin leves are low.

The body doesn't recognize calories. There are no calorie receptors. Calories don't matter. Let me repeat, calories don't matter. Fat, protein and carbohydrates matter (not semantics here - were talking science) and the ratio of these macronutrients effect hormonal response. When carbs are high, insulin is high. when insulin is high, fat storage is favored. That is a fact. And the more we secrete insulin the more insulin insensitive we become. (I suppose this mechanism was either never taught to you or you glossed over this when reading Gary's book where he discusses this from a scientific standpoint in great depth.)

"Insofar as carbohydrate intake increasing insulin levels - true - research shows this many times over. Does this necessarily lead to fat gain? Researh is equivocal, if not contrary to the insulin theory - at least in a caloric deficit."

It boils dowen to the AMOUNT of carbohydrate. Don't you see? Sure - on an 800 calorie diet fat is lost (let's forget lean mass loss for now for the sake of argument). But how many grams of carbs are in an 800 calorie diet? If protein and fat are kept adequate for health, barely any. On an 800 cal a day diet, you'd need at least 60gms protein (240 cals) 30gms fat (270 cals) which leaves 290 cals. from carbs. This = 73 grams of carbs. Viola! a low carb diet!

"Fred - since you ignored the studies I posted earlier, I will re-post them. If you have any evidence that counters it, again, please post away.... unfortunately, I am unable to post. I will post them at the JP forums. Fred - if you feel you have anything in the way of studies to present in your defense - please post them. If not, I wouldn't bother showing up. Although - I would encourage you to stay on the boards and contribute your opinions."

What studies are you asking for? I've posted several. YOU my friend ignored the A to Z study. Care to comment?

Also James, in an earlier post you said:

""Adipose tissue is regulated by a wide variety of factors. Insulin is only one regulatory hormone. Basically, anything that can activate or inhibit the adipocyte plasma membrane adenylyl cyclase system will affect adipose tissue lipolysis. This includes catecholamines, growth hormone, interleukin-6, tumor necrosis factor-alpha, and plasma atrial natiuretic peptide (ANP), to name a few. Catecholamines and ANP, in particular, are strong regulators of adipose tissue metabolism, just as strong as insulin."

In thinking and reading further on this, I see they're talking about lipolysis and lipid mobilization -- i.e., getting fat out of the fat tissue. We're also talking about putting it there. This ANP is admittedly new to me. Although my reading indicates that it is released by heart cells in response to, among other things, exercise and calorie restriction. Makes sense, because the heart works primarily on fatty acids, so if the heart is starved for fuel, it makes sense that it would secrete a hormone that would liberate some for it from the adipose tissue. The question then is whether the adipose tissue restocks afterward; whether this ANP works when insulin levels are elevated, and whether of course there is any other connection to the diet. Remember the thing about insulin is it is the direct connection between diet and adipose tissue. Growth hormone, for instance, has no such direct connection.

Reading the article you cited I admit it is very complicated stuff. They talk about how the various factors influencing lipolysis -- hormones, central nervous system, etc -- could effect obesity, but they never talk about the simplest possible explanation -- the insulin and insulin resistance.

[Mike]

James - thank you for clarifying my position - you have the absolute right of it. "Calories matter" is not the same as "a calorie is a calorie".

James' take on insulin reflects my understanding of it - that it is but one factor - not THE factor. Although I'm a little perplexed. In one sentence you say;

"Insulin doesn't make us fat"

And in the next breath you say;

"Increases in insulin via high carbohydrate diets favor fat storage and inhibit fat mobilization"

So... how is this different?

Insofar as carbohydrate intake increasing insulin levels - true - research shows this many times over. Does this necessarily lead to fat gain? Researh is equivocal, if not contrary to the insulin theory - at least in a caloric deficit.

Fred - since you ignored the studies I posted earlier, I will re-post them. If you have any evidence that counters it, again, please post away.

... unfortunately, I am unable to post. I will post them at the JP forums.

Fred - if you feel you have anything in the way of studies to present in your defense - please post them. If not, I wouldn't bother showing up. Although - I would encourage you to stay on the boards and contribute your opinions.

James - pop in as well! The people of these boards would really benefit from your knowledge (if you aren't a member there already).

http://forums.jpfitness.com/diet-nutrition-supplementation/39279-fierce-conversations-part-1-calories-vs-carbs-insulin.html

[fred hahn]

"Adipose tissue is regulated by a wide variety of factors. Insulin is only one regulatory hormone. Basically, anything that can activate or inhibit the adipocyte plasma membrane adenylyl cyclase system will affect adipose tissue lipolysis. This includes catecholamines, growth hormone, interleukin-6, tumor necrosis factor-alpha, and plasma atrial natiuretic peptide (ANP), to name a few. Catecholamines and ANP, in particular, are strong regulators of adipose tissue metabolism, just as strong as insulin."

Yes but how are these affected by diet? This is the main point. We can only eat and exercise to control body fat accumulation. IOW, we only have control over so much. Those factors beyond our control (assuming we are in good health) are not nearly as important as what we have control over.

"For a detailed review, see Lafontan & Langin, Lipolysis and lipid mobilization in human adipose tissue, Progress in Lipid Research, 2009"

I'll take a look.

********
I'd like to hear how you would describe excess body fat storage without elevation in circulating insulin.
**********

"That's not the point, Fred. The point is that insulin is not the only factor regulating fat metabolism. Your view that insulin makes you fat is overly simplistic and does not consider all the other factors that regulate fat metabolism."

Insulin doesn't make us fat - I never said that. Insulin is a powerful anabolic hormone as well. If you'd listen for a second, what I am saying is increases in insulin via a high carbohydrate diets favor fat storage and inhibit fat mobilization. That is a fact. It is that simple James.

"For example, protein stimulates insulin secretion. There are some proteins that are just as insulinemic as carbohydrate. So why aren't you telling people that protein makes you fat? According to your logic, it should."

In a word, glucagon.

[James Krieger, M.S., M.S.]

Adipose tissue is regulated by a wide variety of factors. Insulin is only one regulatory hormone. Basically, anything that can activate or inhibit the adipocyte plasma membrane adenylyl cyclase system will affect adipose tissue lipolysis. This includes catecholamines, growth hormone, interleukin-6, tumor necrosis factor-alpha, and plasma atrial natiuretic peptide (ANP), to name a few. Catecholamines and ANP, in particular, are strong regulators of adipose tissue metabolism, just as strong as insulin.

For a detailed review, see Lafontan & Langin, Lipolysis and lipid mobilization in human adipose tissue, Progress in Lipid Research, 2009

********
I'd like to hear how you would describe excess body fat storage without elevation in circulating insulin.
**********

That's not the point, Fred. The point is that insulin is not the only factor regulating fat metabolism. Your view that insulin makes you fat is overly simplistic and does not consider all the other factors that regulate fat metabolism.

For example, protein stimulates insulin secretion. There are some proteins that are just as insulinemic as carbohydrate. So why aren't you telling people that protein makes you fat? According to your logic, it should.

[fred hahn]

Glad you agree with that last statement as it is a direct quote from the Fifth edition (2009) of Lehninger Principles of Biochemistry which is probably the most respected biochemistry textbook in the business.

And please tell me the other factors that regulate the storage of adipose tissue that supersede insulin.

I'd like to hear how you would describe excess body fat storage without elevation in circulating insulin.

[James Krieger, M.S., M.S.]

**************
"High blood glucose elicits the release of insulin,

*****************

True, if you're not Type I diabetic

********************

which speeds the uptake of glucose by tissues

*******************

"Stimulates" is a better word rather than "speeds". Insulin stimulates GLUT4 translocation to the cell surface, upon which glucose can be transported into the cell.

********************

and favors the storage of fuels as glycogen

*********************

Insulin does favor the formation of glycogen through the stimulation of glycogen synthase.

*****************

and triaglycerols,

******************

Insulin stimulates glucose uptake by adipose tissue and inhibits the release of free-fatty acids from triglyceride storage.

*****************

while inhibiting fatty acid mobilization in adipose tissue."
****************

True.

While your last statement is true, Fred, there is a host of other factors that regulate adipose tissue storage and body fat. Your last statement is only a small piece of the overall picture.

[James Krieger, M.S., M.S.]

*************
but I do believe that Mike asserted somewhere that calories count. This means that he feels that a calorie is a calorie.
*************

See, Fred, you have proven with this statement that you have constructed a strawman. The concept that "calories count" is not equivalent to the concept that "a calorie is a calorie."

***********
He continues to sidestep every example I give and even lists studies to support his arguments which counter them.
*************

He hasn't sidestepped anything. And as far as studies, he SHOULD be listing studies to support his argument. You're the one sidestepping the evidence he provides. Mike provides empirical data. You provide quotes from books and misconceptions of biochemistry and how insulin functions. Mike, in a number of posts, also asked you to provide empirical evidence to support some of your assertions, for which you failed to do.

**************
Exercise DOES indeed make some people hungry.
***************

Argumentum ad nauseam. Repeatedly asserting this statement, with no empirical evidence to back it up, has about as much value as claiming invisible pink unicorns live in the sky.

[fred hahn]

"Mike has already done an adequate job of responding to your posts, but I will say Fred that you've constructed a strawman by claiming that Mike & I believe that "a calorie is a calorie." Neither one of us have made such an assertion."

I'd have to look back through the posts. but I do believe that Mike asserted somewhere that calories count. This means that he feels that a calorie is a calorie.

As far as his responses being 'adequate' is concerned, I don't agree. He continues to sidestep every example I give and even lists studies to support his arguments which counter them.

Exercise DOES indeed make some people hungry. Have you read Walter Willet's Nutritional EPI book?

And again, as I asked Mike, do you agree with the following:

"High blood glucose elicits the release of insulin, which speeds the uptake of glucose by tissues and favors the storage of fuels as glycogen and triaglycerols, while inhibiting fatty acid mobilization in adipose tissue."

[James Krieger, M.S., M.S.]

Mike has already done an adequate job of responding to your posts, but I will say Fred that you've constructed a strawman by claiming that Mike & I believe that "a calorie is a calorie." Neither one of us have made such an assertion.

[Alevoor]

This can well turn out to be a real issue after it becomes known more widely and when it reaches more and more common people, but for the time being, the ongoing debate is still inconclusive and it may work against your plans if you were to remove exercises from your routines.

Although I have relied on the combo of exercises and diet, my focus has always been on the dietary part of it which worked for me time and again but how can I tell which one contributed more and which less? I think, both of them contributed to in their respective and proportionate ways.

Nevertheless, the entire entry and all the comments made for a great reading.

Alevoor

[fred hahn]

Before I join in, please tell me if you agree with the following:

"High blood glucose elicits the release of insulin, which speeds the uptake of glucose by tissues and favors the storage of fuels as glycogen and triaglycerols, while inhibiting fatty acid mobilization in adipose tissue."

[Mike]

I decided to post our debate topics on the JP fitness forums. It's far better for quoting and it would be interesting to get a variety of takes on the issues.

I hope you will come and defend your position. I have divided the debates into 2 parts for simplicity and have summarized the evidence.

http://forums.jpfitness.com/diet-nutrition-supplementation/39279-fierce-conversations-part-1-calories-vs-carbs-insulin.html

http://forums.jpfitness.com/diet-nutrition-supplementation/39280-fierce-conversations-2-more-important-adequate-protein-carb-reduction.html

[Mike]

What paradigm do you feel I'm stuck in Fred? The one based on science and that different dietary patterns work for different people? I'll take that paradigm any day over a defacto one-size-fits all dietary and exercise philosophy.

I have no time for a long-winded post, but I will summarize as follows;

You: Exercise makes you hungry therefore you eat more to compensate for it.

Me: In the majority of studies, exercise does NOT cause overeating.

Please note, I provided evidence of this, you provided nothing but fruitless attempts to discredit them.

You: Carbs/insulin is what makes people gain weight. Calories don't matter and the metabolic advantage is scientific fact. As long as you reduce carbs, your weight will go down (because of the insulin response).

Me: Calories do matter (please note, however that I never said a calorie is a calorie). Metabolic advantage has never been shown to exist.

Again note that I provided tightly controlled studies that validate my position on calories and ones that punch massive holes in the insulin theory. You provided a reasonable study that lacked a tightly controlled environmet like metabolic wards and provided absolutely NO studies to validate your insulin-causes-fat-gain theory.

Me: As long as protein levels are set at adequate levels, how you juggle fat and carbohydrates makes very little difference.

You: It's all about the carbs/insulin.

Once again, note that I provided 2 studies showing that when protein was constant, people lost the same amount of weight despite a variety of carb levels. the Non-keto LC vs. the KetoLC and the Layman study. You provided a study that showed differing protein levels and then proceeded to rip a well-conducted study because of the funding source.

On that note, if we go there, we would have to eliminate all the Volek, Forsythe, Westmen and the Low carb vs. low fat vs. mediterranean study of last year.

I will only point out a flaw if it is relevant to what we are comparing;
Eg. The Forsythe/Volek study: Reasonably well conducted, decent sample size and control and pretty decent length relatively speaking. However, the study did not prove;
a) a metabolic advantage - self-reporting is an inherent flaw to prove or disprove.
b) that the carbohydrate reduction was responsible for the weight loss (protein levels were different.
c) didn't control for glycogen/hydration loss - traditionally, most very low carb diets peak at 2-3 months. In that time, glycogen losses are the highest - that is why a study of that nature usually evens out over the long run (as evidenced by the 1 year study you posted). So while you may think I'm changing my tune regarding the length of this study, I'm not - it's relative to what you using it to prove.

What this study set out to find (and did a very good job in doing so) was demonstrate a significant lowering of insulin concentrations and favorable insulin sensitivity. But again, we disagree on much of a difference this actually makes when it comes to fat loss.

To end - the best diet is one that people can stick with that keeps them in a caloric deficit. Low carb can be a very good conduit for this, many can achieve the same (and science proves this) by keeping protein intake sufficient - regardless of fat/carb levels. If they can stick with this diet longer term by keeping carbs moderate instead of very low than they should. The opposite is also true.

[fred hahn]

Mike I don't have a lot of time for this anymore. But I'll discuss this issue with you one more time.

You said:

"Sure, full text is here http://www.ajcn.org/cgi/content/full/83/5/1055
Please note: No difference between ketogeninc and non-ketogenic low carb diets. On isocaloric 1500 cal diets, the following was the macro breakdown;Protein levels are virtually equal and carb/fat content varies quite substantially - no difference."

First off I can throw back at you the length of the study - a mere 6 weeks. You've already invalidated the 12 week studies I cited as too short, so...

Secondly, it wasn't a ward study so back at ya once again.

Third, did you see who the lead researcher is? That's right none other than Dr. Barry Sears himself - a man with a strong agenda to squelch VLCD because he is a 40/30/30 advocate. IOW, powerful researcher bias.

4th - this is the only study I have ever seen to show this to be the case. Got another?

This invalidates this particular study.

The A to Z study

http://jama.ama-assn.org/cgi/content/full/297/9/969

tells a very different story.

The VLC Atkins group squashed all other diets, including Sears' in every respect. Only when the Atkins group added carbs back into their diet did the playing field levle a bit. No researcher bias on this study, it was a year long as opposed to 6 weeks and had 311 participants as opposed to 20.

"Conclusions: In this study, premenopausal overweight and obese women assigned to follow the Atkins diet, which had the lowest carbohydrate intake, lost more weight and experienced more favorable overall metabolic effects at 12 months than women assigned to follow the Zone, Ornish, or LEARN diets."

"I would be hesitant to say that protein is the absolute only factor, as physiology is too complicated to make such blanket statements. It has, however been proven time and time again that protein is satiating. Perhaps a protein/fat combo combined with reduced sugary, white carbs does the trick - who knows for sure. My point is that in terms of macro composition, keeping protein adequate - not lowering carbs, per se - seems to be the trump card (see the study above)."

Why do you keep saying this? Do you realize that what you are saying contradicts your previous statements RE calories? Are you suggesting that if one is protein deficient by 20 grams all one needs to do is increase his protein to this extent all the while keeping calories the same and he'll lose fat? Why do you continue to ignore the biochemistry of fat storage and release?

"Check out Layman’s AJCN study:
For the first 2 weeks, participants ate a diet of 15% protein, 35% fat and 50% carbs. Over the next 2 weeks, they ate the same amount of calories, but ate 30% protein, 20% fat and 50% carbs. The 3rd stage was 12 weeks long and participants got to eat however many calories they wanted, provided they remained at 30% protein and 20% fat. Over the 12 weeks, participants ate an average of 441 Calories less and lost an average of 10.8lbs in weight and 8.2 pounds in fat mass.Note that in the 2nd and 3rd weeks, carbs were the only constant at a pretty high (extremely high by your standards) level. Participants actually lost more fat when they upped protein and dropped fat. I'm not suggesting this as a recommendation, just showing that protein seemed to be the key factor - as there was no carb reduction. "

Seemed to be, but it was not. You're missing something. First, what was the total calories in this study? Where the diets hypocaloric? If so, then they would be losing fat anyway due to a reduction in total amount of carbs from what they were eating before entering the study.

Also, the combination of carbs and fat lends itself to greater fat storage. When carbs are high and dietary fat is high that is a recipe for greater fat storage than is carbs are high, fat is low and protein is high. That is why a diet high in fat must be low in carbs or more fat will be stored as fat. By lowering the fat content of a high carb diet, less fat is stored.

This study does not tell us that carbs are not the main factor in fat storage. It tells us that when carb intake is relatively high (50%) and fat intake is also relatively high, more calories will stored as fat. Protein is utilized for tissue repair and growth. So more tissue remodeling occurs and less fat storage when protein is increased and fat is decreased. And you say that 441 less total calories were ingested - which calories were decreased? I'll bet the carbs.

It's NOT that more protein in = more fat loss. Do you see? So your example pokes holes in nothing I've said. You do fight hard to stay stuck in the paradigm don't you? May I ask why?

Do you agree or disagree with the following:

"High blood glucose elicits the release of insulin, which speeds the uptake of glucose by tissues and favors the storage of fuels as glycogen and triaglycerols, while inhibiting fatty acid mobilization in adipose tissue."

[Mike]

"There are many studies that compare low fat to low carb and keep protein virtually equal."

Really? Do share.

The two studies I cited had protein for low fat and low carb at 20% and 28% respectively. If you want to argue that the 8% protein made all the difference in the benefits that the low carb group received over the low fat, you'd have to come up with a VERY good reason for that."

On a 1500 cal. diet, 20% protein is only 75g. I don't know what the average person weighed in this study but if they were say 200lbs, this puts them right around the low end of the RDA of .8g/kg. Contrast this with the 28%, which equates to a much larger 105g of protein - a full 30g more. So yes, this could very well made the difference in the already relatively small fat loss advantage of the LC group.

"12 weeks is short? Another grasp at straws. How long must the study be for you to deem it long enough? I could say the same in opposition to the studies you cited that supposedly indicate that exercise has no effect on hunfer right?"

When it comes to establishing whether a certain dietary pattern is more effective, than yes - it is too short to draw a conclusion that one is better than the other. The same doesn't apply to exercise and hunger, unless you think that months down the road you'll all of the sudden have the urge to gorge from the exercise you did 2 months prior.

“So what are you suggesting? That the all the folks in the VLC group snuck exercise into the fray and all the LF subjects did not? You're graspinf at straws to not see the benefits of LC over LF. “

My point is that is lacks the control of a metabolic ward study. I’m not saying it’s completely invalid, it’s just the weight loss could easily be attributed to glycogen loss, hydration flux, etc. That would be a much better explanation than the exercise : )

“Show me a study that supports this claim (that when protein levels are high enough, the carb/fat level doesn’t matter much)”

Sure, full text is here http://www.ajcn.org/cgi/content/full/83/5/1055
Please note: No difference between ketogeninc and non-ketogenic low carb diets. On isocaloric 1500 cal diets, the following was the macro breakdown;

Carbs
Keto: 33g (9%)
Non-keto: 157g (42%)

Protein
Keto: 125 (33%)
Non-keto: 117 (31%)

Fat
Keto: 100g (60%)
Non-keto 50g (30%)

Protein levels are virtually equal and carb/fat content varies quite substantially - no difference.

“I did already citing the Volek studies. The RDA for protein is between 10% and 35%. Given this, Volek doubles the RDA.”

Fred – I said when protein levels are more or less equal – 20% and 28% is a difference of about 30g of protein at 1500 calories – this is pretty substantial.

“But when they ARE doubled, carbohydrate is also reduced. So you can't say that the superior fat loss is solely due to the increased protein now can you”

I would be hesitant to say that protein is the absolute only factor, as physiology is too complicated to make such blanket statements. It has, however been proven time and time again that protein is satiating. Perhaps a protein/fat combo combined with reduced sugary, white carbs does the trick - who knows for sure. My point is that in terms of macro composition, keeping protein adequate - not lowering carbs, per se - seems to be the trump card (see the study above).

Check out Layman’s AJCN study:
For the first 2 weeks, participants ate a diet of 15% protein, 35% fat and 50% carbs. Over the next 2 weeks, they ate the same amount of calories, but ate 30% protein, 20% fat and 50% carbs. The 3rd stage was 12 weeks long and participants got to eat however many calories they wanted, provided they remained at 30% protein and 20% fat. Over the 12 weeks, participants ate an average of 441 Calories less and lost an average of 10.8lbs in weight and 8.2 pounds in fat mass.

Note that in the 2nd and 3rd weeks, carbs were the only constant at a pretty high (extremely high by your standards) level. Participants actually lost more fat when they upped protein and dropped fat. I'm not suggesting this as a recommendation, just showing that protein seemed to be the key factor - as there was no carb reduction.

Insofar as your insulin theory – insulin's label as a "fat storage" hormone is incomplete and flawed. I’ve provided evidence that punches holes in it already.

[fred hahn]

VG comment John.