Saturday, April 02, 2011

Fasting insulin and weight loss and calories-in vs calories-out

I had this exchange in the comments on a previous post:


Frank said...

Hi Peter.

I'd say that I pretty much agree with your post. Insulin and caloric deficit are not mutually exclusive, ie, low-insulin could enhance fat loss on a caloric deficit or, looked from another perspective, a caloric deficit could enhance fat loss if someone has low insulin level. 

I have only one question for you. For the sake of it lets make thing black and white. 

What do you believe is the most important thing to do, in order to achieve weight/fat loss 

a) be in a caloric deficit (your insulin level does not matter much) 

b) having a low-insulin level (it does not matter much if you're in a caloric deficit or not). 

Again, in real life, I don't believe they exclude each other, but if you could fix only one to have a weight loss, which one would you fix? Calories or insulin? 

The way I see it is that, as you stated, insulin inhibits lipolysis, but more lipolysis does not equal more oxidation. It still has to be matched to energy expenditure. In that case, calories would be the most important factor. That's my point of view and it could be wrong. 

I'm just wondering if you agree to some degree with it, because reading your post, I get the idea that you do. 

Thanks for your time.


Peter said...

Ah Frank, now there is a question.

Without caloric deficit (and I want uncoupling proteins, sleeping metabolic rate, spontaneous movements, etc, etc, etc, everything, accounted for) there will be no weight loss.

But, in real life, if I could only alter just one, it would be insulin.

I would expect no weight loss but I would expect improved health.

What else matters?




There is a flaw in the answer I gave to this question. It's working at the Noddy level of calories-in vs calories-out.

The Noddy approach is perfectly adequate to explain the findings of GnK's paper (PR's weight loss excepted, if she genuinely ate all she was asked to), but embarrassingly stupid in the real world.

Let's look at calories-in vs calories-out in the fixed caloric phase of the Abredeen study.


Calories-in is total calories in to metabolism. There are two sources. Those from the diet, let's assume (incorrectly) these are genuinely all of the 2000kcal/d on offer. Then there is the supply of free fatty acids metered out from adipocytes under the regulation of insulin. Maybe a little glycogen, but I'll ignore that for the discussion.

Under LCHF conditions more FFAs are accessible due to lower insulin levels. More get used and, from Table 1, only 1930kcal of food are needed to supplement those calories-in from adipocytes in order to meet total metabolic needs. Hunger is low. Calories supplied are clearly able to meet voluntary calories out. Demand is within the limits of supply. Some food is refused.

Under MCMF conditions the higher insulin level allows less calories to be supplied from fat in to metabolism (adipose derived calories-in fall), so calories-in accepted from food spontaneously increase to the full 2000kcal/d. Under the study conditions we cannot tell if 2000kcal plus reduced adipose FFA supply is enough for as much metabolic activity as was possible under low insulin conditions. What if it is not? Now the real question is: Does lipolysis automatically increase to supply all needs for calories out? Why should it? Lipolysis is controlled by insulin. Insulin is high, lipolysis restrained.

If there is any shortfall in the calories from fat plus 2000kcal, there are only limited calories available to burn. You can't burn what you don't have. Calories-out would drop because they simply cannot exceed the supply available. I would expect the participants to automatically reduce their calories-out. There is no free lunch. Calories-out = calories-in. All need to be accounted for.

Is it be possible to force lipolysis in the face of hyperinsulinaemia to increase FFAs from fat to a higher level without lowering insulin?

Of course it is. There are other hormones in addition to insulin. You can throw around adrenaline, growth hormone, glucagon and probably a truckload of others I've not thought about. You can add in direct sympathetic nervous system innervation of adipocytes to effect lipolysis if you like. But these mechanisms come with a price. The price is hunger.

I think it's called working up an appetite.




In the Aberdeen study the attempt to maintain caloric intake failed during the LCHF phase because low insulin increased caloric supply from fat. Higher insulin in the MCMF phase limited calories-in derived from adipose tissue and may well have set a cap on total calories available for use during this higher insulin phase.


In Frank's thought experiment it might be easy to fix dietary calories-in, but people might refuse some of them if insulin was low enough for adipose tissue derived FFAs to be available.... If they ate all of their calories but wriggled in their chair a bit more because they had more calories available then the concept of calories-out being fixed is lost....



I'll just finish with a clarification of this phrase from another commenter:

"lipolysis is not beta oxidation"

This is, ultimately, accurate. That doesn't stop it being bollocks.

A rather more perceptive view is the situation comes from, of all places, the lipophobic cardiologists who published on FFAs and myocardial ischaemia:

"The rate of fatty-acid uptake and oxidation by the heart is controlled by their availability [33]"

Oh, interesting. Availability. A supply led system. Hmmmmmm. I would guess most FFA burning tissue would follow cardiac muscle. Now I can't quite remember what effect insulin has on lipolysis and FFA availability. Silly me.

Peter

91 comments:

  1. Hi Peter,

    There is no glycogen in heart muscle. Heart muscle "burns" whatever heart muscle can get. There is usually a lot of fat around hearts. Dietary fat is delivered to the back of the heart via the lymphatic system.

    There is glycogen in skeletal muscle, as well as IMTGs. What skeletal muscle "burns" is determined by skeletal muscle glycogen level, fitness level & exercise intensity, to name a few. See http://nigeepoo.blogspot.com/2011/02/its-all-in-days-work-as-measured-in.html

    Presenting skeletal muscle with high serum FFAs won't shift it to burning FFAs when there is sufficient muscle glycogen present.

    I do agree with you about better appetite control on LC, though.

    RE Working up an appetite: Fasted cardio sucks! It makes me want to eat, eat & eat some more afterwards. However, post-meal cardio doesn't have this effect, so that's what I do to keep my muscles working properly. I don't have much if any NEAT/SPA. I'm posting from the comfort of my 3-seater sofa. :-D

    Nige.

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  2. More thoughts to ponder... How much calories out are in our waste products? That is to ask, what is the thermodynamic efficiency of the body? How does a measure of heat convert to mass? Why is it necessary to keep track of a boundary condition deemed true by the laws of science? Call me a skeptic, but counting calories seem obsessive and superstitious.

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  3. @js290: This has been discussed on GT's blog. See http://www.garytaubes.com/2010/12/inanity-of-overeating/#comment-112860588

    Very little dietary fat is egested, even at high fat intakes. Ditto for dietary carbohydrate & protein.

    Grossly over-eating protein can result in some unabsorbed peptide chains reaching the colon. This is easily detected as it results in smelly flatulence. Raw egg whites are also poorly absorbed (~50%).

    Insoluble fibre is egested but it isn't included in calorie counts (not in the UK, anyway). Soluble fibre is partly absorbed as SFAs after conversion by gut bacteria.

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  4. Hello Peter,

    I am newbie so please forgive the potential ignorance of the following question. I am neither a doctor nor do I play one on TV-

    If one has extirpated dietary sources leading to insulin resistance (fructose, gluten, excess O-6 from veg oils, etc), but continues to be MCMF rather than LCHF, would you expect the individual to eventually regain insulin sensitivity and lose weight to a healthy set-point even in the face of higher carb intake?

    Or once ones metabolism becomes deranged (slightly or significantly), is low carb a requisite to regain insulin sensitivity? I assume it depends upon the extent of derangement.

    Thanks,
    Aravind (aka Kitavin in a past life)

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  5. "Under MCMF conditions the higher insulin level allows less calories to be supplied from fat [...]"

    If the carbs don't come with toxins (e.g., lectins), the higher insulin level will only be postprandial. You nicely explained by what mechanism carbs can lower fasting insulin levels in your potato diet post.

    My take: when you avoid toxic carbs (e.g., wheat, corn, excess fructose), then carb levels become unimportant. This seems to work for the Kitavans.


    "Lipolysis is controlled by insulin."

    In part. Cortisol, growth hormone, epinephrine and thyroid hormone stimulate it [1]. Note that insulin also stimulates and inhibits the same appetite regulating neurons in the hypothalamus as leptin [2].
    So: insulin ↑ ⇒ appetite ↓ (for postprandial levels).


    "But these mechanisms come with a price. The price is hunger."

    For hyperinsulinaemia this is probably true. So again: stay away from carb related toxins.

    But for a healthy person, it seems to be like this:
    Fat ↑ ⇒ leptin ↑ ⇒ appetite ↓, thyroid ↑ ⇒ lipolysis ↑, metabolism ↑.


    John

    References:
    [1] Nussey S., Whitehead S. Endocrinology: An Integrated Approach. 2001. http://www.ncbi.nlm.nih.gov/books/NBK30/box/A61/
    [2] Konturek P.C., et al. Neuro-hormonal control of food intake: basic mechanisms and clinical implications. J Physiol Pharmacol. 2005 Dec;56 Suppl 6:5-25. http://pmid.us/16340035

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  6. This last few weeks I have brought my protein intake down to OD levels and upped my fat intake.

    I havent gained weight, I *look* thinner (decreased BF) but my weight is stable. Gym sessions have been down to 2x week. I am not controlling calories consciously, just protein (restricting it to only egg yolks and cheese/meat). Some days I have eaten a lot of calories, like yesterday, in which on top of my normal day, I ate an entire pot of OD ice cream, using the same recipe you posted (~1000kcal). I am eating one meal a day (23/1).

    Using CRONOMETER, my daily calorie intake averages 3000kcal. This is with ~15% protein, 5% carbohydrates (although is non existent ATM, no veggies, fruit, starch or alike), 80% fat. According to OD, I should be eating 2700kcal.

    CICO would dictate I should be a pig by now. Less protein means less thermogenesis (less "metabolic advantage"!), more fat means more storage (considering I eat one big meal, ASP should be working like mad) and lipotoxicity (FFA are bad); Less exercise means less EE (I move less, eat more).

    Hmmmmm.....

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  7. Nigel,

    My understanding, skeletal muscle does not burn glycogen at any high rate except during high intensity activity. Also that high muscle glycogen facilitates muscle insulin resistance.

    Also, from Marieb EN. Human Anatomy and Physiology, fifth edition. New York: Benjamin Cummings, 2001(quote from p. 974):

    “The liver, cardiac muscle, and resting skeletal muscles actually prefer fatty acids as an energy fuel.”

    From Whitney and Rolfes: “Fat supplies 60 percent of the body’s ongoing energy needs during rest. During prolonged light to moderately intense exercise or extended periods of food deprivation, fat stores may make a slightly greater contribution to energy needs.”

    Source: Whitney and Rolfes, Understanding Nutrition (Belmont CA; Wadsworth, 2005), p.158.

    IOW, skeletal muscle burns fat as the predominant fuel under all circumstances except high intensity contractions (sprinting, lifting, etc.), and exercise under the lactate threshold actually increases the proportion of FFA used as fuel.

    And these data are produced from studies of people on high carbohydrate diets.

    As I understand the data, most carbohydrate consumed by most people (inc. Kitavans) gets converted to fat and stored in adipose before it ever enters cellular energy metabolism. Glycogen is rarely drawn down (only in fight or flight efforts), and when expended, it is restored in great part by recycling lactate, not from dietary carbohydrate.

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  8. Hi Peter. I'm a bit baffled how you can be such a calories in/out kinda guy, but you yourself maintain a stable bodyweight of around 65 kg and a BMI of 20 on about 3000 kcals a day (as discussed in the comments of a previous post about 2 years ago, the name of which I don't remember.I remember we did a FitDay breakdown and found you were eating about 3000 to 3500 kcals/day).

    I'm not trying to counter any of your arguments in this post or the last one. They all make complete sense to me. I'm just wondering how you yourself reconcile calories in/out with your own weight loss experience.

    Do you think you're skinny because the diet makes you eat less? Because it doesn't seem to be doing that for you.

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  9. Hi Gunther (and js290 and John and Lucas),

    As always, there is only so much you can include in one post. From my own point of view the scales went in to storage on 24th September 2010 and my life has been utterly chaotic since then. As far as I can tell I'm weight stable and have absolutely no idea of my caloric intake.......... I have a lot of time for some sort of set point hypothesis but it is clearly push-able by diet. Nit picking or micro management of calories is strictly for thought experiments.

    All of the studies in the last few posts were carried out with people who were overweight. So something is broken in these people. As you know, my suspicion is that the break is primarily hepatic in location and all else is a set of knock on effects. Although John's link to oxidised lipids and hypoinsulinaemia is forcing me to look at MODY1 and iron overload as methods of developing a form of diabetes. That's without thinking at the mitochondrial level...

    So does appetite plummet for normal weight people who low carb? My own experience is an emphatic yes but only in the short term. My weight was only inching up over the years. It dropped precipitately on LC and came back up to current weight fairly quickly. I'm never hungry in the way I remember. You know, the "I have to eat NOW!" feeling. That is a fading memory, funny to watch in work colleagues though. But I still like eating and cycled in the 64 point something kilo range, back when I had scales. I also notice that I never do anything slowly at work. Having a work-experience student in tow brings home how quite how un-energetic most people are! My job has me on my feet and active all day. I don't really get tired. It's useful. I was called Tigger or Tigs in one job.

    Don (and Nigel), I have a paper looking at intensive insulin therapy. Without actually checking I think it was T2Ds treated with insulin therapy to a semblance of normoglycaemia on a lethal ADA diet. Of course they gained weight, another giggle at the satiety inducing effects of insulin, and improved their insulin sensitivity. But the change in muscle insulin sensitivity was through reducing skeletal glycogen stores from overload to normalish levels. Insulin sensitivity improved but was completely related to improved non oxidative uptake to glycogen stores, not to acute oxidative use.

    I suspect insulin does facilitate glucose oxidation but acute shifts in normal people put glucose in to glycogen in muscles.

    Peter

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  10. Compulsory reading for those who believe that "calories in = calories out."

    http://en.wikipedia.org/wiki/Atwater_system

    The calculated caloric energy of foods is nothing but crude 100 years old estimates with limited relevance to actual human digestive processes.

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  11. Don,

    you are correct. Most carbohydrates are immediately "banked" as fat and drawn upon to provide energy as needed.

    The gut basically shuts down during intense physical activity so it is pointless eating carbohydrates while exercising to increase endurance. So called sports drinks are no more effective than plain water.

    The average western adult never reaches the anaerobic threshold so they are always relying on fat as their primary fuel.

    Humans evolved to to sprint for 5-10 seconds and jog/walk long distances. We didn't evolve to perform marathons or any other high intensity steady-state physical activity.

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  12. Like Peter I'm always hyper-energetic. I also radiate heat like a furnace. I wear nothing but shorts (no shirt) around the house unless it is below about 22C. At the moment it is 26C and I am just in shorts with fan blowing on me.

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  13. @Nigel,

    the amount of stool material produced varies enormously depending on diet. A traditional Inuit diet will produce <50g per day of stool matter. A Kitivan diet will produce >500g/day of stools.

    Stools contain up to 15% fat, 3% protein and 4% sugars (mostly as bacteria). That is why many animals such as dogs and pigs will readily eat human feces.

    In a theoretical Kitivan poo we have:

    7.5g fat = 67Cal
    1.5g protein= 6Cal
    2g sugars = 8Cal

    Total = 81Cal

    That is ~30,000Cal/year or equivalent to 4kg of body fat.

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  14. As im aware insulin will override all other hormones, including GH, only Catecholamines will override insulin.

    "Does lipolysis automatically increase to supply all needs for calories out?"

    My answer would be no. Fat people always complain of being tired all the time. And feel more energetic AFTER loosing weight ( i.e. after they have gained access to alot of fat burning )

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  15. Peter,
    “Low insulin allows calories from adipose FA to compensate for reduced dietary intake thus reducing appetite” is a great hypothesis to explain why low carb diets tend to be hypocaloric. And you have provided numerous examples of the observation (people eat less on low carb). Are there any good studies supporting that mechanism specifically? Could you think of one that would? I have a few in mind but would like to hear your thoughts.
    -Bill

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  16. Hi Aravindan,

    Sorry I missed this one last night.

    Insulin resistance is utterly essential for survival during either fasting of VLC eating. If you ran your muscles on glucose when you were only eating 20g/d of carbohydrate your brain would be non functional.

    The world of nutrition perennially confuses this with pathological insulin resistance in the presence of carbohydrate intake, a problem condition with a number of causes.

    If you are pathologically insulin resistant you can side step the problem by carbohydrate restriction, or fasting, and the normal physiological insulin resistance kicks in and makes your pathological problem irrelevant. Reversing pathological IR would mean making a type 2 diabetic able to go out and eat a giant pizza with double fries and a litre of soda on the side with normoglycaemia. I don't see that happening.

    blogblog, I have this idea of feeding a raw food vegan on 2000kcal/d of sawdust. Insulin would fall, weight would plummet and they could market their stools as firelighters, producing about 2000kcal of them each day.... I said I had a warped sense of humour.

    William, not that I'm aware of, although most of the studies I cited are interventional and Aberdeen looked at hunger using VAS. There are lots of studies looking at various brain hormones but looking for antiobesity drug development. Anything but dropping carbs. As blogblog has commented, there's not a lot of science in nutrition research...

    Peter

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  17. Hi Peter. So walking around most of the day at a vet's office is burning up to 3500 kcals/day? I'd like to see a lumberjack who skips the pancakes and doubles the bacon and eggs before starting work then.

    It still doesn't add up, but that could be due to the outdated Atwater System, as blogblog says. Or you could just be metabolically gifted. I mean, I like moving around and even work at a standing desk, but I still have to stop at 2500 kcals/day or I gain weight (though this is without any hunger, cravings or feeling deprived).

    After 30 or 40 years on the SAD, maybe we are underestimating the damage caused when we concentrate solely on weight loss. It may just take several years of VLC "treatment" for some of us to get full access to fat stores. Though come to think of it, Kwasniewski isn't very skinny either. But this could just be a reflection of his recommendation for much higher BMI.

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  18. "I'm never hungry in the way I remember. You know, the "I have to eat NOW!" feeling."

    Me neither. No hunger on low carb, but also no hunger when I started adding carbs ('safe starches' as Paul Jaminet would call them) again. Doing a 24 hour fast is really easy for me.
    Like Don said, most calories you eat end up as fat. So whether adipocytes supply fatty acids which were created from carbs you ate or fat doesn't matter. What matters is that the adipocytes do supply fatty acids, i.e., no hyperinsulinaemia.

    Eating fat instead of carbs just bypasses the need to convert the carbs to fat. In other words, it seems to be a slightly more efficient way to replenish your fat stores. On the other hand, eating fat will not replenish your liver's glycogen, eating (some) carbs will.


    John

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  19. And as a tie-in to the discussion with Frank, the Fasting Insulin Problem may be where exercise comes in to assist in stubborn obesity (ie. something's "broken"). It's not essential for the undamaged, but may be the deciding factor for others to get their fasting insulin where it needs to be for full access to fat stores.

    Get this memo out to certain chunky bloggers taking it out on evil Taubes.

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  20. Dr Lutz said healthy young adults often adapted to a VLC diet within a few weeks, most middle aged people took a a few years and old people (70+) often never adapted to VLC diets.

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  21. @Gunther,

    "Though come to think of it, Kwasniewski isn't very skinny either. But this could just be a reflection of his recommendation for much higher BMI."

    I'm not skinny either. I have a BMI of around 24.5. I'm eventually aiming for another 10kg (90kg).

    I remember a scientist describing the physiques of 100,000 year old human remains he had excavated in Africa - as "built like rugby players" - tall and extremely muscular.

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  22. Gunther, back in the days when I counted everything I was weight stable at around 63kg on 2000kcal. I remember discussing this with Stan. Both of us were eating well below OD calories and were slimmer than Optimal. Nowadays I'm around 64kg and undoubtedly get through >3000kcal some days but I suspect there are others when there is not enough time for lunch or I skip some creamy drinks. For odd practical reasons I'm fermenting milk rather than yogurt at the moment and making up calories with (hormetic) creamy cocoa drinks. How many I get through in a day is a bit random...

    Peter

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  23. blogblog,

    You may well have an excellent point here. It bugs me that I want to weigh what I did at 20.... It's easy to do, but is it healthy? Is this a psychiatric disorder????????

    Peter

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  24. blogblog, the Lutz observation is priceless. Maybe there's nothing to be done after a certain age. I'm 40 now and started VLC (with lots of mistakes and false starts) when I was 37. Before that I was Cordain-style paleo for 2 years (and not losing weight or feeling much better).

    The way you're looking with your BMI will depend on your body height and musculature, so I don't know if I'd be looking like a rugby player at BMI of 25. That's a bit too close to what I looked like on the SAD!

    But based on this Optimal BMI question, I can hear a new post brewing, no Peter? Do we want to be skinny after all? It's weird, since GCBC claims that anything that causes obesity will also cause diseases of civilisation. Now where does that leave us?

    It's an Kwasniewski vs. Taubes cage match!

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  25. "carbohydrates are stored as fat before being metabolized"

    This go's against everything that physiological science tell's us, is there a source for this?

    According to most studies de novo lipogenesis isn't a significant pathway in carb metabolism and carbs are only turned to fat under certain dietary circumstances(like eating a 85%+ carbohydrate diet). When you eat a high carbohydrate diet your glycogen stores increase from around 400g to 800-900g(which is why in my opinion high carb blast low fat away for atheltic individuals).

    If you check out Nigels blog you can see that you start using carbs for energy at 24% of maximum intensity, at 50% half your expenditure is carbs. 50% of maximum is not just sprinting or lifting...

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  26. Peter,
    I'm 182cm tall. I weighed 60kg at 18. I now weigh 80kg at age 48 (after a couple of months of deliberate gorging).

    My waist has only increased from 76cm to 82cm in 30 years.

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  27. Higher BMI on the OD will not necessarily mean higher fasting insulin (like with high BMI on the SAD), so perhaps this is where Taubes and Kwasniewski diverge. VLC fatness is different????

    It just gets weirder and weirder.

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  28. Gunther,
    "But based on this Optimal BMI question, I can hear a new post brewing, no Peter? Do we want to be skinny after all? It's weird, since GCBC claims that anything that causes obesity will also cause diseases of civilisation. Now where does that leave us?"

    BMI obviously needs to be tailored to your own physique. I gain muscle easily and add bulk evenly over my body. I could probably handle a BMI of 30 without being "obese" as long as I did a little bit of exercise.

    Other people are "obese" at a BMI of 20 eg sedentary older people who eat high carb/low protein diets.

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  29. Thanks so much for the response Peter. I understand the distinction you are making with pathological IR. Perhaps my original question was worded poorly. In your potato post, you wrote the following -

    "The more of a problem you have with obesity the less likely you are to lose weight or experience appetite normalisation (translates as access to adipose tissue calories). Ultimately the ability to live on varied macronutrient ratios comes down to how broken you are, especially your liver. Why a broken liver requires low carbohydrate eating is another post."

    I have already taken the need to eliminate wheat/gluten, sugar/fructose, and excess O-6 as a given...so I am not suggesting you articulate a path to allow for gluttony in the form of pizza, liters of soda, etc :-)

    I am just wondering how low carb one needs to go....or is the macronutrient ratio not so important if one avoids the inflammatory components that cause IR problems to begin with. Perhaps I am implicitly assuming a diabetic condition as not been realized yet, simply being overweight. Specifically, In my case I'm down 15 lbs on a MCMF diet and have another 10-15 lbs to go. Key focus for me has not been macronutrients, but wheat/sugar/vegetable oils avoidance.

    So ultimately I guess I am trying to get you to write the post to answer "why a broken liver requires low carbohydrate eating". Very demanding of me, I know :-)

    Kind Regards,
    Aravind

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  30. "most carbohydrate consumed by most people (inc. Kitavans) gets converted to fat and stored in adipose before it ever enters cellular energy metabolism."

    Is there a source for this?

    From what I've seen the science says otherwise

    "Glycogen storage capacity in man is approximately 15 g/kg body weight and can accommodate a gain of approximately 500 g before net lipid synthesis contributes to increasing body fat mass. When the glycogen stores are saturated, massive intakes of carbohydrate are disposed of by high carbohydrate- oxidation rates and substantial de novo lipid synthesis (150 g lipid/d using approximately 475 g CHO/d) without postabsorptive hyperglycemia. "
    http://www.ajcn.org/content/48/2/240.short

    De novo lipogenenis isn't really utilized for carb metabolism unless you massively overfeed on a 85%+ carb diet.

    Also you claim glycogen is only an important fuel source at max intensity but this is not true. If you read gunthers blog or search google scholar you will find out that glycogen starts to be used at around 25% of max intensity and is half of the fuel used when 50% is reached.

    If your not totally fcked from past diet experiences high carb diet>>>high fat unless your goal is to be sedentary. Increasing glyocgen stores by double trumps anything low carb has to offer imo. The above doesn't apply to fattys or lazy people :)

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  31. Don said...
    Nigel,
    My understanding, skeletal muscle does not burn glycogen at any high rate except during high intensity activity.

    The data in my first link suggest otherwise. At ~50% of maximum exercise intensity (jogging/running), there's a ~50/50 split in energy derived from fat & carbs.
    Peter said...
    Don (and Nigel), I have a paper looking at intensive insulin therapy. Without actually checking I think it was T2Ds treated with insulin therapy to a semblance of normoglycaemia on a lethal ADA diet. Of course they gained weight, another giggle at the satiety inducing effects of insulin...
    High-carb, high-insulin diets produce roller-coaster blood glucose, as large inputs lead to large errors. High insulin may well be satiating, but low blood glucose is definitely very hunger-inducing!
    blogblog said...
    The calculated caloric energy of foods is nothing but crude 100 years old estimates with limited relevance to actual human digestive processes.
    You still don't get it, do you? Calorie counts are inaccurate. So fucking what? The fact that calories count, has nothing to do with counting calories. When are you going to get that through your thick skull?
    blogblog said...
    Don, you are correct. Most carbohydrates are immediately "banked" as fat...
    Wrong again! Try reading Use and storage of carbohydrate and fat, by Jean-Pierre Flatt.
    blogblog said...
    @Nigel,
    Stools contain up to 15% fat, 3% protein and 4% sugars (mostly as bacteria).

    Are you shitting me? If stools contained 15% fat, you'd be up shit creek without a paddle. I think your maths sucks!

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  32. "You still don't get it, do you? Calorie counts are inaccurate. So fucking what? The fact that calories count, has nothing to do with counting calories."

    So calorie counts are inaccurate but still a good guide.

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  33. Blogblog,
    What does it mean , to be unable to get adapted to VLC? How does it get manifested? I am trying to convince my mom who is 74, to go to VCL as an Alzheimer prevention strategy, because my grandma has it. Is it too late to start for my mom?

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  34. Atwater factors, though averages and imprecise, somehow manage to hold up fairly well in practice. There are innumerable studies performed with weight maintaining diets where TDEE is measured and intake matched, or intake monitored during weight stability to ascertain caloric needs.

    Mostly when it doesn't hold up it's because the individual is an outlier in some respect, e.g. they may have a significant malabsorption isssue that only becomes apparent when they reduce calories they can absorb and replace them with those they can't.

    There's really not a whole lot of evidence for significant differences in the metabolic pathways. After all, most ATP comes from reactions and pathways common to all three micronutrients.

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  35. @gigi: Most obese are awash in free fatty acids. They're not locked away tightly enough.

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  36. Galina L,

    I know of two people successfully managing Alzheimers, one is using chronic LC diet (not anyone I have had any hand in) and the other has asked the nursing home to supplement with medium chain triglycerides and has updated me off blog. The nursing home staff have never seen improvements as produced by the MCTs.

    I doubt it's ever too late but MCTs probably need a less extreme diet.

    Peter

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  37. Hi Galina,

    as you age your body takes progressively longer to repair damage.

    I assume that people in their 70s have accumulated so much damage that they have trouble adapting to a VLC diet.

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  38. Peter, another thing that doesn't make much sense to me given your extremely low bodyweight is that if you're burning about 3000 kcals/day by being active at your job, why isn't your appetite through the roof when you sit down to eat?

    I would assume some kind of set-point would kick in as you burn up calories at work. Just like exercise works up an appetite using the same process, hence insignificant weight loss (or for those on the SAD, weight gain).

    Have you ever pigged out enormously for a few days to a week on VLC just to see what it does to you? It seems like in order to get yourself to JK's Optimal BMI levels, you'd have to eat upwards of 5000 kcals a day. Assuming you're even capable of reaching that BMI or eating that many calories.

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  39. Nigel,
    I will gladly defer to your superior knowledge.

    I mean I only have a BSc in food science, a research Masters in biotechnology, a Grad Dip in exercise science from one of the world's leading human movement schools and experience dating back to 1986.

    How could I possibly know as much about any of these topics than an egotistical foul-mouthed former engineer. This person apparently gets his own nutrition and exercise advice from blogs written by equally arrogant ignoramuses.

    Nigel,if you weren't so incredibly ignorant and arrogant I could explain that stools are up to 80% bacteria by dry weight. The principal component of bacteria is lipids ie fat.

    So if I to was take some poo (or your brain - they're essentially indistinguishable) and dry it and analyse it I would discover that it was up to 15% fat.

    Ruminants such as sheep and cattle get most of their energy from cultivating bacteria in their guts and using specialised enzymes (acid-resistant lysozyme) to digest these bacteria.

    Cattle on natural pastures get about 80% of their energy from volatile fatty acids and only about 2% from carbohydrates.

    Even more amazing is that these vegan cattle frequently enter a state of intense ketosis during pregnancy or lactation.

    [http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/80900.htm]

    Who would have thought that vegan cattle are on a VLC ketogenic diet?

    In fact nearly all adult mammals on a natural diet derive most of their energy from fat and protein in an approximately 4:1 energy ratio - from big mean polar bears and scary lions right down to fluffy little bunny rabbits and cute little mice. Mammals do this either by direct consumption of other animals or by gut fermentations.

    So if most other mammals are on a permanent VLC diet why shouldn't carnivorous humans be as well?

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  40. And come to think of it, how do OD followers or JK himself ever reach Optimal BMI levels if VLC is causing such ramped up access to fat stores? Shouldn't they be jittering and sweating these calories off just like you?

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  41. Nigel,
    you are in serious need of professional psychiatric help.

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  42. gunther,

    those of us who gain weight on VLC are mostly gaining muscle not fat.

    Glasgow is cold so that may be why Peter is thin. Maybe he needs to eat some of that famous Glaswegian delicacy - the deep fried Mars bar.

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  43. @blogblog: . Most carbohydrates are immediately "banked" as fat and drawn upon to provide energy as needed.

    Do you have any citations to substantiate this claim? In humans the exact opposite is true where only large excesses are converted to fatty acids to any great extent.

    @All: The lipophobic cardiologists recognize that burning certain fatty acids for fuel is not optimal for cardiac myocytes. If memory serves it is because fatty acid "burning" requires more oxygen than glycolysis and/or accumulation of ceramides are likely culprits.

    Peter, maybe I should send you a bouquet.

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  44. Thank you, Peter and Blogblog. My mother doesn't have any signs of the Alzheimer yet, just usual old age thinhs - sort of high blood pressure problem, middle body obesity, also acid reflux (manifested as too much mucus coming up her throat), and I was thinking about the degree of LC she could be convinced to achieve. Your answers helped me to decide. At least she stopped using sugar and limited bread by now. She eats too much fruits and sunflower oil.

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  45. @Don

    From memory, the proportion of energy contribution from muscle glycogen is related to both intensity of exercise and the amount of glycogen in the muscles being used. Muscle glycogen use can be high at lower intensities when the muscles are fully saturated after CHO loading, then the inverse rule applies more as the muscle glycogen levels drop to normal levels. From my experience as an athlete over the years, the body likes to maintain a certain level of muscle glycogen based upon the training stimulus, not too high or too low. If it is too high the muscles can feel all jammed up and stiff during aerobic exercise(hence TdF riders riding 30 miles on rest days to stay loose).

    This does kinda relate to the post. Taking the above in the opposite direction, in an acute situation where muscle glycogen stores are very depleted following exercise, during post-exercise refeeds the body will preferentially oxidise fats and conserve glucose regardless of significantly elevated insulin levels. Up until the point at which an individual's 'normal' glycogen status has been normalised, glucose is directed towards these stores in order to satisfy the body's over-riding drive for normalisation of its muscle glycogen stores in preparation for the next exercise bout.

    Ref - Skeletal muscle fat and carbohydrate metabolism during recovery from glycogen-depleting exercise in humans -

    http://jp.physoc.org/content/548/3/919.full.pdf+html

    The above is obviously an extreme stress type situation and does not really detract from the anti-lipolytic effects of insulin under normal circumstances.

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  46. @Galina L,

    My mother will be 70 next year, and her mother had Alzheimer's. About seven months ago, I suggested that my mother avoid sugar and eliminate wheat. Her gastric reflux vanished within a week. Within a few months, she'd shed 20 pounds and now weighs 116 (what she considers her ideal weight). She otherwise eats as she wishes in both food selection and quantity and her weight remains stable. I have noticed an incredible difference in her energy level, motivation, and clarity of mind (she does not have Alzheimer's - I'm referring to her re-found quick wit).

    Wishing your mother good health.

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  47. @CS

    You said:

    "The lipophobic cardiologists recognize that burning certain fatty acids for fuel is not optimal for cardiac myocytes. If memory serves it is because fatty acid "burning" requires more oxygen than glycolysis and/or accumulation of ceramides are likely culprits."

    Once again I think you are confusing pathology with the normal physiologic state.

    Fatty acids are only a problem in the setting of ischemia, where there is not enough O2 being supplied. Fatty acids, of course, cannot be burned without O2. So glucose may be better in the ischemic setting.

    So the problem is the LAD choked off by plaque, not the "toxicity" of the fatty acids.

    Cardiomyocytes love fatty acids.

    @Blogblog

    Nigel knows everything because he read it somewhere. Didn't you know that? Being a foul-mouthed sort just emphasizes how much he knows.

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  48. Kurt,

    additionally a healthy person isn't going to develop ischemia unless they do something really, really stupid - like running a marathon.

    HGs tend to stick to short sprints and jogging/walking when they go hunting eg an 8-10km/h average speed. This creates very high cardiorespiratory fitness safely because the heart rate is only high for a few seconds at a time.

    In fact you can get super-fit just by 10x sprinting/walking 30m once a week. It takes only 3-5 minutes.

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  49. @Cliff:

    Thanks for reminding me of that study:

    http://www.ketotic.org/2011/04/extra-glycogen-de-novo-lipogenesis-and.html

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  50. Galina,
    the best approach for older people is gradual change in diet over at least 1-2 years.

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  51. Again from memory, the ATP yield per unit of oxygen is only about 5-10% lower from fat vs CHO.
    Cardiac stroke volume increases well in response to LSD exercise at only 60% VO2. No need for too much stress.

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  52. @Paul,
    high intensity interval training is far more effective than steady state training. Intermittent training will achieve more in five minutes a week than steady state will achieve in a few hours per week.

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  53. You claim to have such superior knoweldge of nutrition blogblog but then you make statements like this "Most carbohydrates are immediately "banked" as fat and drawn upon to provide energy as needed."
    and ignore everyone who asks for citations... Your just another arm chair wannabe scientist :)

    You go on to make even more retarded claims like the one that HG's only practice specific exercises. Clearly you haven't heard of persistence hunting.
    http://www.youtube.com/watch?v=fUpo_mA5RP8 http://en.wikipedia.org/wiki/Persistence_hunting

    Maybe you should go get more useless degrees so you can make more smug biased false comments.

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  54. Proof that its impossible to gain weight on a low fat high carb diet www.30bananasaday.com(I don't advocate what these people do)

    They eat well over there glycogen needs but if you look at the pictures you can see they are all extremely skinny. I've done the diet eating 4000+ calories of date smoothies on a daily basis for a prolonged period I did not gain anything. This is totally anecdotal but its enough evidence for me.

    Don tried to claim they are skinny because they can't absorb the food properly due to fiber but this is pretty retarded considering there diet is based around fruit a relatively fiber poor food.

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  56. This comment has been removed by the author.

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  57. Aravindan, I tend to make certain assumptions about people.

    In general people can read. If they read a comment with expletives throughout they might draw certain conclusions, as I do, about the value of the comment.

    I sort of hope people who read here can draw their own conclusions.

    Peter

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  58. Peter

    You are better man than I am. Having said that, and to be more productive, any response to my post from a few days ago (my second post in this thread) regarding "why a broken liver requires low carb?".

    Thanks and warm regards,
    Aravind

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  59. On low carb less work for the liver and liver has chance to recover?

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  61. @Cliff.
    why don't you read what I said?

    Persistence hunting is not steady state exercise

    Persistence hunting is alternative jogging and walking with an average pace of only 8-12km/hr. It may include a few brief sprints.

    Why do I need to quote papers for every statement I make? When you know enough about a topic the knowledge becomes internalised and you don't even think of the sources.

    An experienced doctor doesn't pull a textbook off shelf every time they see patient to check facts.Why? Because they rely on their memory.

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  62. @Cliff,
    fruit typically has 2-5% fibre levels - mainly as pectins and polyols.

    Raw food diets often have >50-100g per day fibre intake.

    Vegans are skinny because raw plant material is mostly indigestible. The nutrients are locked inside the cellulose cell walls and can't be accessed.

    Raw food vegans may be eating 4000+Cal a day but they are lucky to absorb 1000-2000cal of those calories. Most of what goes in their mouths ends up undigested in the toilet bowl.

    Cellulose and uncooked starches starches can't be digested except by colonic fermentation.

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  63. On the topic of human feces...there is a lot of varition in content cited by various researchers.

    "Dry weight" is the only useful way to present percentage data, since water content is both high and variable.

    Huge percentages of dry weight consist of bacteria, and the bacterial content and distribution of species vary greatly.

    It is generally assumed that most digestible calories (i.e., everything except fiber) are extracted before reaching bacterial digestion in the gut, but there actually isn't all that much evidence on the topic--or on how much this varies between healthy individuals. (Or between healthy and unhealthy individuals.)

    If you consider the kinds of things that would have to be done to get real details, in humans, in a broad sample, to demonstrate exactly what is happening between mouth and anus, it's easy to see why what we have is largely conjectural.

    We are symbiotes. And there is increasing evidence that our gut flora may affect all manner of things.

    Probably including our energy budget. 35-45% of the dry weight of human feces is bacteria...

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  64. Aravindan,

    There will be a post.

    Peter

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  65. @David,
    before I switched to VLC I suffered very badly from Crohn's. I would often see totally undigested food in my stools. One day I had just weighed myself ons some precision electronic scales at the gym when I had a sudden urge to defecate. I had a massive surge of watery diarrhea. I reweighed myself and found I was 3.0kg lighter!

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  66. Just to beat a dead horse on the calories in/out discussion and your low weight, I came up with a theory. Perhaps your reliance on the cream as your main caloric base is the cause, due to its being an "expensive" food to digest.

    I can imagine dairy products, especially those high in bacteria such as yours (fermented 3 days, if I remember correctly) would be a lot of work for the body too. This idea is not an attempt to refute what we know about low insulin for fat loss, just a possible explanation for why your BMI would be even lower than someone else eating an 80% fat diet and relying on other, more easily digestible foods.

    Fine, call me a wacko, but does anyone know if dairy is any harder to digest than, say lard? If it takes much longer for the intestines to process and break down, we could have a winner.

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  67. In other words, the higher the level of exogenous processing for a food, the higher its "caloric content", in a way.

    It kind of adds calories when you "digest" your food before eating. I wonder if this applies to dairy, at least when heavily fermented or raw.

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  68. Gunther,
    fat inhibits the growth of most gut bacteria. That is why a cat can turn a 450g can of cat food into one very small stool.

    I'm guessing Peter is actually burning a lot of energy just to keep warm in the cold Glasgow climate.

    Metabolism is only 20% efficient so it is easy to increase calorie consumption by a huge margin just by keeping cool. Polar explorers need about 6000Cal/day to maintain their weight.

    Traditional Inuits kept their housing at about 30-32C in winter. They also wore extremely warm fur clothing. This would have saved a huge amount of food energy.

    In hot humid climates it is virtually impossible to lose heat. This is possibly why obesity is far more prevalent in hot places like Mexico, southern US, Micronesia and Australia than in cold climates like Finland, Korea and Japan.

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  69. Hi blogblog, the climate thing is certainly relevant, but Peter was this weight before he moved to Glasgow, and in any case I would think his office and home are kept in fairly livable conditions or he'd have a tough professional and social life. :-)

    I'm thinking the enormous amount of work devoted to the breakdown, fighting of bacteria and bacterial waste products which the body has to do for many hours after eating a whole bunch of highly fermented cream may be a factor, in addition to the low baseline insulin Peter's got between mealtimes. After we factor out the calories devoted to actual digestion, he may not actually be eating as much as 3000-3500 kcals a day.

    Just an idea. Stone at will if its ridiculous.

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  70. Gunther,

    a high fat diet produces far less bacterial growth than a normal diet. Fat and protein are absorbed extremely effectively. So you would expect a high fat diet to actually provide more usable calories than a SAD.

    VLC diets promote fat utilisation. This means more movement and more body heat. In turn this means feeling hotter and wearing less clothing and keeping rooms cooler.

    The skin radiates heat at any temperature below 34C. So unless Peter has his house and workplace like a tropical greenhouse he will be losing a great deal of heat.

    I live in a subtropical climate where the summer temperature averages around 33C and 80% humidity. This induces extreme lethargy because any muscle activity - even gentle walking - causes severe overheating.

    I eat a virtually identical diet to Peter. Yet I weigh 82Kg. Arguably the main difference is that I don't expend anywhere as much energy on physical activity or heat loss due to living in a hot humid climate.

    I have a few Irish friends working in Australia. They are 10-20% lighter than the locals despite a similar diet. However these Irish people wear less clothing and keep their houses far colder than we locals do.

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  71. @Gunther,

    USA obesity map. Note the strong correlation between climate and obesity.

    http://calorielab.com/news/wp-images/post-images/fattest-states-2010-big.gif

    Heating dwellings above 20C doubles the risk of obesity.



    A couple of interesting papers - free full text:

    Obesity (2011) 19 1, 13–16. doi:10.1038/oby.2010.105

    Brown Adipose Tissue, Whole-Body Energy Expenditure, and Thermogenesis in Healthy Adult Men

    Obesity (2010) 18 1, 190–195. doi:10.1038/oby.2009.167

    Microbiota and SCFA in Lean and Overweight Healthy Subjects

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  72. Hi Blogblog, these are interesting but they are all measurements of people on the SAD in the West. I'm not sure it applies to a guy like Peter. I'd like to see HG bodyfat levels around the world to make a comparison that applies to VLC and other paleo oriented diets and lifestyles.

    Anyone with a correctly working endocrine system and lifestyle should probably be adjusting to most reasonable temperature changes, and they would eat more or less as a result of increased/decreased expenditure. Enormous swings in bodyfat wouldn't be seen on a Real Food diet, I should think. It just wouldn't be practical from an evolutionary standpoint.

    HGs have very low BMI compared to ours and most of them live in tropical or subtropical climates. And the logic of low temperature = low bodyfat would imply that the Inuit should be rail thin on 10,000 kcals a day, which is not the case, especially in Inuit women.

    Thanks for the info. I'm still holding out for a "net calorie / digestion expenditure" explanation. I realise it doesn't explain why you're more than a third heavier than Peter on the same diet, but there are height differentials and perhaps background damage on the SAD to account for this. You're also actively trying to gain weight while Peter is not.

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  73. blogblog said...
    Nigel, I will gladly defer to your superior knowledge. I mean I only have *insert list of impressive qualifications here*
    Yawn! Not another "Appeal from authority"? Did you know that Ph.D. actually stands for "Piled higher & Deeper"? ;-p

    Sorry about the f-bomb, but some of the utter crap that a supposedly well-educated person like you comes out with just beggars belief.

    Nigel, you are in serious need of professional psychiatric help.
    Pot, kettle, black, matey! :-D

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  74. Kurt said...
    @Blogblog
    Nigel knows everything because he read it somewhere.

    Yes, in your blog ;-p

    Didn't you know that? Being a foul-mouthed sort just emphasizes how much he knows.
    Tell Richard Nikoley that, because he drops lots of f-bombs. Hmmm, what's that smell? I do believe that it's the stench of hypocrisy - again.

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  75. @Gunther,
    all the HGs and pre-agricultural societies that have been well-studied have lived in very marginal environments. They probably aren't realistic representatives of early human lifestyles. Modern HGs, such as the Kalahari Khoisan, seem to be around 10-15% shorter and 30-40% lighter than their early East African ancestors.

    The East African highlands where humans evolved are actually quite cool. Daytime temperatures are always below 25C and nights are often below 10C. Being naked in a cool climate will cause a lot of heat loss.

    People don't become fat overnight. It usually takes decades. A 20Cal/day change will result in a 1Kg annual weight variation.

    Studies by that US army have shown that soldiers use only 2000Cal/day in the tropics vs 6000Cal/day in the Arctic to perform the same tasks.

    Unless you have lived in the tropics you can't understand how difficult is to undertake any physical activity or even maintain body temperature without air-conditioning.

    A sedentary female in a hot humid climate will find it very hard to reduce calorie intake to the ~1000-1200Cal/day needed to maintain her weight. Increased physical activity isn't an option.

    Until about 50 years ago most people simply couldn't afford to eat more food or heat their houses to compensate for weight loss. They gained some weight in summer and lost weight in winter.

    Two hundred years ago the average European peasant had a very real chance of starving to death over winter. They would literally stay in bed for 3-4 months to conserve energy.

    I used to live in Ballarat one of the coldest and windiest cities in Australia with a climate similar to southern England. I only weighed 65kg. When I moved to subtropical Brisbane I gained about 10kg in the first year without any major changes in my diet

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  76. @Gunther,
    Peter and I both eat about 3500Cal/day. We apparently eat very similar foods with an emphasis on fermented dairy foods. I'm also a chilli and dark chocolate enthusiast.

    The main variable is that I live in a hot humid climate that is typically 15-20C hotter than Glasgow.

    Peter is more active because he won't overheat and is losing a lot of extra calories as heat. This can easily create a 1000Cal/day energy difference between the two of us.

    I'm sure if Peter and I swapped cities and maintained out diets that he would gain weight and I would lose weight.

    In fact I also weighed 65kg when I lived in a cold (by Australian standards) climate.

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  77. Hi blogblog, I can't see an Inuit living in a place where he needs at least 6000 kcals/day just to function normally. And in his case, possibly more than a US solder, since he's exerting far more energy on a daily basis and without any of the army's amenities or technology. It just wouldn't be economically feasible for survival to have to eat that much on a daily basis. The Inuit can't afford to stay in bed for 3 to 4 months a year.

    I live in chilly Normandy, but I still have to limit calories to around 2500 kcals/day to stay 69 kgs. Though you're right; in summer I find myself spontaneously eating less, while staying about the same weight.

    You make some good points about exposure to the elements helping to burn calories or to conserve them. My hunch is still that there is much more energy loss taking place through digestion than we are attributing. The Atwater system doesn't consider it at all, neither do any national caloric or nutritional guides that I know of. "Calories" as we know them could be a completely different world when we consider how each food is actually processed in vivo.

    I'd love to see some info on human post-prandial thermal output comparing the same foods with different preparation (raw vs. cooked, large surface area vs. small surface area, hot vs. cold, fermented vs. non-fermented, etc.). I'll keep your observations in mind as we try to figure this out though.

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  78. I have recently upped my calories to 3K from 1500 and find that I am losing body fat now.Its not a lot of food when most calories are from fat either and is very satisfying for me.Could be that the body likes to have a higher metabolism and with keeping the insulin level low thru OD type macronutrient manipulation it behaves optimally.What if 3K is normal for a man to eat and is not excess calories when this man is not doing any type of excessive work??

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  79. blogblogblog said

    "you are correct. Most carbohydrates are immediately "banked" as fat and drawn upon to provide energy as needed."

    BS.

    de novo lipogenesis is very minor pathway even in very obese HUMANS (exclude rats and mice).


    there is a lot of literature about this. like most studies these studies have some flaws, but the consensus is clear. to give you some perception the first study gave 500 g of carbs at once. result: 3-4 g fat made via DNL

    data is still incomplete, but it appears that DNL is even less active in exercising humans.

    Acheson KJ, Schutz Y, Bessard T, Anantharaman K, Flatt JP, Jequier E. Glycogen storage capacity and de novo lipogenesis during massive carbohydrate overfeeding in man. Am J Clin Nutr. 1988 Aug;48(2):240-7.

    Hellerstein MK. De novo lipogenesis in humans: metabolic and regulatory aspects. Eur J Clin Nutr. 1999 Apr;53 Suppl 1:S53-65.

    McDevitt RM, Bott SJ, Harding M, Coward WA, Bluck LJ, Prentice AM. De novo lipogenesis during controlled overfeeding with sucrose or glucose in lean and obese women. Am J Clin Nutr. 2001 Dec;74(6):737-46

    Tappy L. Metabolic consequences of overfeeding in humans. Curr Opin Clin Nutr Metab Care. 2004 Nov;7(6):623-8.

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  80. When I go low carb and then carb up my muscles swell with glycogen with little fat storage...if done right.By right I mean that the longer I take to injst the carbs the better the effect.If I slam sugar drinks it all goes to fat but if I slowly do starch over two to three days my muscles get a ridiculous pump and I look amazing.Sad thing is that the super compensation effect lasts for a day at most.If I continue to eat carbs at high amounts I lose the pump and start getting bad hypo symptoms.

    So yes carbs can go straight to fat IMO.

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  81. @Gunther,

    Hi blogblog, I can't see an Inuit living in a place where he needs at least 6000 kcals/day just to function normally. And in his case, possibly more than a US solder, since he's exerting far more energy on a daily basis and without any of the army's amenities or technology. It just wouldn't be economically feasible for survival to have to eat that much on a daily basis. The Inuit can't afford to stay in bed for 3 to 4 months a year.

    I suggest you read Stefansson on how Inuits lived:

    a) they stayed inside and rested all winter (5-6 months).
    b) they kept their housing very hot and humid (30-33C).
    c) They wore extremely warm fur clothing.

    They were using very little energy to keep warm.

    The Atwater System is based on human experiments. It is accurate to within 10% or so.

    The energy costs of metabolising different foods are only a few percent. This has been confirmed by very carefully controlled metabolic studies and radioactive tracers.

    Humans convert in excess of 95% of calorie intake into heat. No other mammal is able to lose heat more easily. That is why we are such effective persistence hunters. - because we don't overheat like most prey animals.

    To put things into perspective humans use about 20x as much energy per unit body weight as crocodiles.

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  82. @Antero"

    BS.

    de novo lipogenesis is very minor pathway even in very obese HUMANS (exclude rats and mice).


    I said that excess carbohydrate is stored as fat. In sedentary people the glycogen stores are saturated and there is very little glucose uptake by the skeletal muscles. The only other alternative to fat storage is loss of glucose via the urine. This is what happens in diabetics.

    You obviously didn't bother to read any of the papers because none of them actually support your argument.

    1) Acheson et al studied glycogen depleted athletes. Sedentary humans have saturated glycogen stores. Therefore this paper is irrelevant.

    2)Hellerstein mentions that liponeogenesis occurs as soon as muscle glucose uptake is overwhelmed by high carbohydrate intake.

    3) McDevitt says that overfeeding causes substantially increased liponeogenesis.

    4)Tappy says that overfeeding increases liponeogenesis and makes people fat.

    Btw very obese people are normally insulin resistant and have reduced ability to remove glucose from the bloodstream leading to hyperglycemia.

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  83. @Wolfstrike.
    the pumped look from carb loading is mostly water because each gram of glycogen needs 3g of water to be stored.

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  84. Hi blogblog. The Atwater system is based on bomb calorimetry performed by William Olin Atwater around the 1890s. I think most people agree (aside from the US government, of course) that it is hopelessly inaccurate and has nothing to do with how calories are burned or used in the body when the particular food in question is processed.

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  86. blogblog,

    Oh, you were talking only about sedentary, glycogen loaded obese western christian white males. ;) I didn't see you writing that. You said that "Most carbohydrates are immediately "banked" as fat" and I made some assumptions. Even in obese glycogen levels aren't "full" most of the time. Glycolysis is proportional to glycogen levels and is very active in glycogen repleted state. Yes the studies agree that DNL increases considerably with excess carbohydrates. But the carbohydrates that are shunted to DNL are very minor part of the total carbohydrate load. Hence adipose tissue is mostly triglycerides from exogenous fat source. Remember that you wrote "most carbohydrates" and I just couldn't tolerate that. There is no point questioning the fact that excess calories consumed via carbohydrates increases adipose tissue. But it is not (mostly) because of DNL, it's because almost all of the fat consumed is stored in adipose tissue and tightly kept there.

    If you have evidence which shows that "most carbohydrates" are shunted to DNL in HUMANS and in REASONABLE CONDITIONS I would be more than happy to see it.


    BTW I would never suggest carbohydrate based diet to obese sedentary people (or to health conscious lean active people for that matter) for many reasons. My only point was that DNL is not very active in humans.

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  87. @gunther: Atwaters factors were confirmed with bomb calorimeter, but they are human metabolizable energy. IOW they are for a human calorimeter.

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  88. Great blog Peter. Nice info, nice insights, great humor. I'd like your opinion on something: I'm about to lose more than a 100lbs (BMI of 61, non-diabetic, borderline high-pressure) on a diet that would consists of 800 calories of only organic butter (to prevent gallstones) and farmed raised eggs (since it's the least insulogenic food according to insulin index, see http://www.ajcn.org/content/66/5/1264.short?rss=1&ssource=mfr). Good idea, bad idea anyone?

    mpaix

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  89. This comment has been removed by the author.

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  90. Splendid posts, Peter, got me thinking. Check me on this: Has Fructose-Fed Ratty elucidated what gets broken in Mets?

    Rayssiguier found “magnesium deficiency combined with a high-fructose diet [in rats] induces insulin resistance, hypertension, dyslipidemia, endothelial activation and prothrombic changes in combination with the upregulation of markers of inflammation and oxidative stress” - metabolic syndrome IOW.

    Balon found that extra magnesium prevented the development of insulin resistance in fructose-fed rats and concluded “magnesium deficiency and not fructose ingestion per se leads to insulin insensitivity”

    Is this relevant to fructose-fed, magnesium depleted humans? Magnesium blocks calcium ion channels and so lowers intracellular calcium ion content; High Ca(i) prompts cells to overdo their thing – beta cells hypersecrete insulin and so on. Importantly, Xue found Ca(i) inhibits HSL and so fat cells grow fatter – in this view, insulin resistance and obesity are fellow travelers each mediated by magnesium depletion.

    Resnick measured the ratio of ionic magnesium to ionic calcium within cells and found it high in health and lower in obesity, Type II diabetes and insulin resistance (not to scale):

    ********************* Health: 9.8
    ****************** Aged: 7.4
    ***************** Obese: 7.0
    **************** Type II: 5.6
    *************** Hypertensive: 5.0
    ************Obese hypertensive: 4.7
    **********Type II hypertensive: 4.3

    This fits with Reaven’s finding that insulin resistance is increased “in association with obesity, high blood pressure and non-insulin dependent diabetes” and that the effects of these conditions are additive – is our degree of insulin resistance mediated by the ratio of calcium and magnesium ions within our cells? Then magnesium supplements should cure diabetes. But Paolisso found diabetic’s cells accumulate less magnesium when insulin is high and Reddi found they pump less calcium out when blood sugar is high.

    Proposition: these defects may be what actually gets broken in MetS and diabetes.

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  91. @Jordan

    http://jp.physoc.org/content/548/3/919.full.pdf+html

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