tag:blogger.com,1999:blog-1629175743855013102.post3985749828845700816..comments2024-03-28T11:29:46.845-07:00Comments on Whole Health Source: NuSI-funded Study Serves Up Disappointment for the Carbohydrate-insulin Hypothesis of ObesityStephan Guyenethttp://www.blogger.com/profile/09218114625524777250noreply@blogger.comBlogger54125tag:blogger.com,1999:blog-1629175743855013102.post-15549597560143871602016-11-26T11:31:46.223-08:002016-11-26T11:31:46.223-08:00Guyenet said:
"Therefore, this trial was nei...Guyenet said:<br /><br />"Therefore, this trial was neither randomized, nor controlled. I don't know why this decision was made, but it does weaken the result."<br /><br /><br />The following link has statements by Kevin Hall regarding the rationale for lack of randomization of diet order. See the last four paragraphs of the first article by Katherine.<br /><br />http://www.thenutritionwonk.com/single-post/2016/07/07/ROUND-UP-RXNS-Dr-Kevin-Hall-the-Metabolic-Chamber-of-Secrets<br />Anonymoushttps://www.blogger.com/profile/02151097017284865549noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-42033824807859143682016-09-27T20:45:22.651-07:002016-09-27T20:45:22.651-07:00Stephan - Thanks so much for the references. Much ...Stephan - Thanks so much for the references. Much appreciated!!<br /><br />Randyrandyfeingershhttps://www.blogger.com/profile/05633383192317515383noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-14367178271228793552016-09-21T08:37:39.659-07:002016-09-21T08:37:39.659-07:00Hi P1,
I think your speculation is probably corre...Hi P1,<br /><br />I think your speculation is probably correct, although there's no way to be certain. By the end of the experiment, both the energy expenditure and the fat loss rate of the KD period were approaching what was observed during the control period. Basically, after a 4-week physiological adjustment period, the experiment was converging on the finding that macronutrient composition makes little difference for energy expenditure and fat loss-- which would be consistent with other studies. <br /><br />That said, this experiment was specifically designed to test the carb-insulin hypothesis, as posited by Taubes and Ludwig, and it did that. They hypothesized that reducing carb and sugar intake, and in turn insulin levels, would have a robust influence on the amount of fat exiting fat tissue, resulting in accelerated fat loss. Taubes and Ludwig believe that this effect of insulin is so powerful that it trumps other physiological variables, like glycogenolysis and gluconeogenesis. This was clearly shown to be false.<br /><br />To modify your closing statement a bit, I'd say that metabolism is complicated and will continue to defy simplistic models. Stephan Guyenethttps://www.blogger.com/profile/09218114625524777250noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-76234120253638700812016-09-20T20:53:44.458-07:002016-09-20T20:53:44.458-07:00To play devil's advocate - if your summary of ...To play devil's advocate - if your summary of the study design is correct - is the result of this study with reference to ketogenic diets even worth considering since they did not account for the period of glycogen loss, and separately they did not provide for the additional protein required in a ketogenic diet?<br /><br />Had they tried to measure glycogen losses, they could have marked the point in time when glycogen was exhausted and evaluated fat loss from that point going forward. Instead, as you summarize it, the rate of loss of fat in the ketogenic diet might be distorted downward because some of the caloric needs were supplied by glycogen instead of fat. Had they started the measurement of fat loss after glycogen was exhausted, the data would have been cleaner.<br /><br />With reference to protein, apparently the body wanted more glucose and it was determined to supply this by gluconeogenesis from protein. Instead of accommodating that with more protein in the diet, they allowed the body to take it from lean body mass. Had they simply supplied additional protein in the diet and reduced fat calories to keep total calories constant, they might have at least had a better isolation of the effects of insulin going lower.<br /><br />My summary of the study: metabolism is frustrating. :)P1https://www.blogger.com/profile/10150386241231733361noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-75484977978721300302016-09-20T15:29:16.439-07:002016-09-20T15:29:16.439-07:00Stephan,
You don't think this study can serv...Stephan, <br /><br />You don't think this study can serve as a nod to "Carb Nite" by John Kiefer?<br /><br />KimGoodleitzhttps://www.blogger.com/profile/16666130744742105609noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-46260880386844413952016-09-20T09:51:07.110-07:002016-09-20T09:51:07.110-07:00This is a Himworth paper published a year earlier,...This is a Himworth paper published a year earlier, but it's probably based on the same information, and you can see full text:<br /><br />http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1394223/Gretchenhttps://www.blogger.com/profile/17019921800841883073noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-12820274913675827452016-09-20T09:36:31.014-07:002016-09-20T09:36:31.014-07:00Is this increase in insulin sensitivity an increas...Is this increase in insulin sensitivity an increase in mitochondrial function? Or could it be essentially temporary "physiological insulin sensitivity," analogous to temporary "physiological insulin resistance" on a high-fat diet?Gretchenhttps://www.blogger.com/profile/17019921800841883073noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-37060058127245343812016-09-20T08:54:44.294-07:002016-09-20T08:54:44.294-07:00Hi Randy,
Here are some references. The first on...Hi Randy,<br /><br />Here are some references. The first one was published so long ago that I haven't been able to get the full text-- I've only seen the results described in review papers. The one by Dan Porte's group is interesting. The ones by Anderson were done in diabetics and show that a very-high-unrefined-carb, very-low-fat diet reduce insulin requirements. The last one is less convincing than I initially thought because of a lack of statistical significance of a key result.<br /><br />Overall, reviewing the references again, the case doesn't seem as strong as I remembered. There is some evidence to support what I said, but it's not ironclad, in part because some of the very-high-carb, very-low-fat diets were also high in fiber.<br /><br />Himsworth HP. "The Dietetic Factor Determining the Glucose Tolerance and Sensitivity to Insulin of Healthy Men" Clin Sci 2:67. 1935<br />http://press.endocrine.org/doi/abs/10.1210/jcem-67-5-951<br />http://ajcn.nutrition.org/content/52/3/524.short<br />http://www.ncbi.nlm.nih.gov/pubmed/9867084<br />http://www.ncbi.nlm.nih.gov/pubmed/495550<br />http://www.ncbi.nlm.nih.gov/pubmed/495284<br />http://www.ncbi.nlm.nih.gov/pubmed/11237931Stephan Guyenethttps://www.blogger.com/profile/09218114625524777250noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-84598773722976471282016-09-19T18:18:27.602-07:002016-09-19T18:18:27.602-07:00Stephan wrote:
******
"The only macronutrient...Stephan wrote:<br />******<br />"The only macronutrient profile that has been clearly shown to improve insulin sensitivity independent of calorie intake and body fatness is a very-low-fat, very-high-carbohydrate diet."<br />****<br /><br />Hi Stephan - Be interested is a reference to the above.<br /><br />Thanks<br />Randyrandyfeingershhttps://www.blogger.com/profile/05633383192317515383noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-84404749227507197502016-09-16T18:59:26.526-07:002016-09-16T18:59:26.526-07:00Stephan,
Incredibly thoughtful reply. Thank you ...Stephan,<br /><br />Incredibly thoughtful reply. Thank you so much for your time!<br /><br />Looking forward to purchasing your book when it comes out.Anonymoushttps://www.blogger.com/profile/17972651052853333256noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-7409204879899458062016-09-16T03:33:24.897-07:002016-09-16T03:33:24.897-07:00Please comment this article - carbs = insulin = al...Please comment this article - carbs = insulin = alzheimer ?<br /><br />https://www.psychologytoday.com/blog/diagnosis-diet/201609/preventing-alzheimer-s-disease-is-easier-you-think<br />Janushttps://www.blogger.com/profile/14591816948426586279noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-7291797583564717452016-09-15T09:16:22.551-07:002016-09-15T09:16:22.551-07:00Hi tjortho,
The primary problem is insulin resist...Hi tjortho,<br /><br />The primary problem is insulin resistance, not high insulin levels. High insulin levels are a marker of insulin resistance. Insulin resistance promotes noncommunicable disease states like type 2 diabetes and coronary heart disease (http://wholehealthsource.blogspot.com/2015/06/insulin-resistance-predicts-variety-of.html). Reducing carbohydrate intake reduces insulin levels but has little effect on insulin resistance unless body fat is lost. But there is a lot of confusion around this issue because many studies measure insulin resistance indirectly using a measure called HOMA, which is based on fasting insulin and glucose. Since carb restriction lowers insulin levels, this makes it look like it also improves insulin resistance. But when you directly measure insulin sensitivity, you find that reducing carb intake does not improve insulin resistance unless it causes body fat loss.<br /><br />The only macronutrient profile that has been clearly shown to improve insulin sensitivity independent of calorie intake and body fatness is a very-low-fat, very-high-carbohydrate diet. That said, some macronutrient profiles can improve insulin sensitivity via fat loss. So for example, a higher-protein lower-carbohydrate diet tends to reduce calorie intake and body fatness, which can improve insulin sensitivity. Also, just ditching calorie-dense processed foods and eating a whole food based diet can help control calorie intake and body fatness. I believe that CrossFit's approach-- including a Paleo diet and lots of exercise-- increases insulin sensitivity, but that doesn't necessarily mean their mechanism is correct. I'm not familiar enough with CrossFit to say whether or not what they teach is correct.<br /><br />There is no evidence that a higher-fat, lower-carbohydrate diet extends lifespan in any vertebrate species (and certainly zero evidence in humans), regardless of its effect on insulin levels. Rodent studies suggest that a higher-carb diet that's lower in protein and fat optimizes lifespan, but if I recall it also has some negative side effects on growth and reproduction. Also, it's not clear how relevant those findings are to humans.<br /><br />Bottom line: if you care about disease risk, healthy aging, and longevity, you should care about insulin sensitivity more than insulin levels. Staying lean, getting regular physical activity, eating a whole food based diet, getting good sleep, managing stress, not smoking cigarettes, and avoiding excessive use of alcohol and other drugs are likely going to give you a high return on your effort. Most of the rest is details.<br /><br />FYI, my book doesn't spend much time at all on the insulin hypothesis of obesity. It's about the nonconscious brain circuits that nudge us to overeat.Stephan Guyenethttps://www.blogger.com/profile/09218114625524777250noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-71837835038538110942016-09-13T10:42:27.971-07:002016-09-13T10:42:27.971-07:00Stephan,
The focus here (and on your book, I pres...Stephan,<br /><br />The focus here (and on your book, I presume) is on the "insulin-obesity" relationship. I understand the analysis and accept that body fat loss is not a simple matter of macro balancing (low carb).<br /><br />The corollary hypothesis pushed is the "insulin-health" relationship. i.e. Reducing carbohydrate intake-> reduces insulin -> leads to prevention of all insulin mediated disease states. <br /><br />Do you think that corollary hypothesis is well supported at this point? Has it really been tested? Should this be the real motivation for people to limit carbohydrates to only those needed for energy/activity demands?<br /><br />In current application of this, the crossfit community's nutrition teaching advocates high protein, adequate carbohydrate, and eventually a increasing proportion of fat as energy needs increase.....net result is a high fat, moderate carb diet. But the hypothesis that this is better for longevity (due to reduced insulin) is largely via indirect evidence...<br /><br />A penny for your thoughts?Anonymoushttps://www.blogger.com/profile/17972651052853333256noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-16985928441215909552016-08-26T20:18:57.790-07:002016-08-26T20:18:57.790-07:00Maybe the high carbohydrate group lost weight fast...Maybe the high carbohydrate group lost weight faster because it takes more calories to digest carbohydrates than it does to digest fats.onikahttps://www.blogger.com/profile/09584631028448077780noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-168023573130569532016-08-19T22:40:16.220-07:002016-08-19T22:40:16.220-07:00I follow keto, and I would never let the protein g...I follow keto, and I would never let the protein go down to 15%, always at 20-30%. Ianhttps://www.blogger.com/profile/05407187307100246667noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-9711596275751190612016-08-18T12:18:53.157-07:002016-08-18T12:18:53.157-07:00Wow, I had no idea there was this behind the scene...Wow, I had no idea there was this behind the scenes battle royale going on between LCD gang and the CICO gang all the while obesity is still a huge issue. <br />I've lived the struggle, in my family obesity has been the norm. I know the pain, frustration and hopelessness that comes from doing all you can to lose weight only to gain it back. I maxed out at 330lbs in August 2003 and went on to lose 100 pounds by July 2004 and another 30lbs since then. I have experience. <br /><br />IS it possible that everyone is somewhat right? Glucagon burns fat and can't co-exist with insulin right? So would keeping insulin low from longer periods of time increase fat burning? <br /><br />Also though we need carbohydrates to keep leptin up because studies have shown that high calories /high fat do little for leptin while high calorie/high carb boosts it up. <br /><br />Energy balance is just that and losing weight and keeping it off like I did is intentionally controlling the ups and downs. Anonymoushttps://www.blogger.com/profile/00604965095078218781noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-14125556230742195722016-08-05T12:09:24.469-07:002016-08-05T12:09:24.469-07:00Per Ludwig's comment, it seems worth noting th...Per Ludwig's comment, it seems worth noting that it would be even better had there been a crossover design of some kind (sorry if my terms are wrong): either having the groups go back and forth a couple times, or having part start with HCD and the other start with the LCD/KD. I was wondering about lagging effects myself---metabolic changes that might show up at more than four weeks out from the dietary change. <br /><br />Not really convinced of the insulin hypothesis, but it seems like "devastating" might be a little bit too strong. Rickhttps://www.blogger.com/profile/15718339895075968309noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-28873392331795728872016-07-16T15:26:43.943-07:002016-07-16T15:26:43.943-07:00The carb insulin hypothesis needs refining thats a...The carb insulin hypothesis needs refining thats all. The science has evolved, and so must the hypothesis<br /><br />High levels of insulin and glucose cause irreversible differentiation of pre-adipocytes into fully mature adipocytes, basically a growth of the adipose tissue depot. While lowering the insulin and blood glucose on Low-carb diets only causes adipocyte shrinkage, not de-differentiation or apoptosis. Theres your carb-insulin hypothesis of obesity. <br /><br />Kindkehttps://www.blogger.com/profile/15841418412425329998noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-28267804320058690442016-07-15T06:08:47.354-07:002016-07-15T06:08:47.354-07:00"Evidently, the total quantity of circulating..."Evidently, the total quantity of circulating energy in the blood is regulated tightly enough that even radical changes in diet have little impact on it."<br /><br />This is pretty significant. Are there other literature references to this?<br /><br />I would have thought that after glycogen depetion on the HFLC diet the first source for additional glucose would be gluconeogenesis from bloodstream protein rather than the catabolism of lean mass. Yet if bloodstream energy is tightly controlled bloodstream protein would not be available, and the signal for catabolism would be immediate.thhqhttps://www.blogger.com/profile/07256574635664867999noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-14911700837193193672016-07-14T14:43:03.020-07:002016-07-14T14:43:03.020-07:00Mikej26, inefficiency is sought because people are...Mikej26, inefficiency is sought because people are fat. They have the fuel to burn, and a desire to burn it. De-tuning the engine is exactly what's sought here. If a condition like that of nephrogenic glycosuria were possible to induce, losing sugar into the urine, without adverse effects, that kind of a fuel leak would be highly sought.Roberthttps://www.blogger.com/profile/15361114843115796546noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-13583499088785976112016-07-14T12:09:20.501-07:002016-07-14T12:09:20.501-07:00Why are low-carbers & keto dieters getting ups...Why are low-carbers & keto dieters getting upset about this study? It's not showing that keto diets don't work. It's showing that keto diets don't work <b>due to Taubes, Ludwig et al's Carbohydrate-Insulin Hypothesis Of Obesity</b>.<br /><br />If a low-carb or keto diet's working for you and it's sustainable, carry on doing it. Why quibble over details?<br /><br />The only people who should be getting upset about this study are those who profit from promulgating the Carbohydrate-Insulin Hypothesis Of Obesity i.e. Taubes, Ludwig et al.Nigel Kinbrumhttps://www.blogger.com/profile/03368973941328529619noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-82698607501537379632016-07-14T07:29:59.783-07:002016-07-14T07:29:59.783-07:00I would have loved to have seen a high-protein var...I would have loved to have seen a high-protein variant as well. 15% protein in a 2700 kcal diet amounts to 405kcal or about 100grams of protein. Considering atheletes take in about 2gr(or more) per kg of bw, I would have love to have seen the effects of a truly high in protein diet...zzzzhttps://www.blogger.com/profile/15957018313007282648noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-66931684139216922002016-07-13T19:48:49.293-07:002016-07-13T19:48:49.293-07:00The problem with the concept of the metabolic adva...The problem with the concept of the metabolic advantage is that everyone who is trying to argue that there is one is trying to show that the body will be burning MORE calories. In reality what seems to happen in the long term is that LESS dietary calories are needed in order to maintain energy homeostasis. It has to to with the efficiency at which ATP can be derived from different energy substrates. While everyone knows that carbs are 4 cals and fats are 9 cals. When you look at the actual amount of ATP that can be produced from the two, there is a wider spread in energy production of ATP than the caloric values represent. Largely because the energy from carbohydrates or glucose will end up producing more waste energy as heat than fatty acids will. So per unit of oxygen consumed, you get more ATP and less waste heat via fatty acids than you do from glucose. <br /><br />So if you're using calories as a metric to gauge energy metabolism you're missing the point entirely. You want maximum conversion of energy substrate into ATP, not maximum consumption of calories. The former is akin to an efficient fuel use, the latter is inefficiency.<br /><br />So do you want more usable energy produced from less total fuel supply, or less useable energy produced from a greater total fuel supply? <br /><br />Only in the human body would people think that burning more fuel is a good idea and it's silly.<br /><br />Looking at auto racing as an example. The car that can get the most power whilst also getting the best fuel mileage will need to make fewer pit stops and ultimately will win when compared to the cars that need to consume more fuel to get the same output.<br /><br />In this case efficiency is a clear advantage.<br /><br />However, if the goal was to just burn the most gas you probably want less efficiency, and you could do so by detuning the engine, but it'll end up putting out more emissions and it'll suffer longevity wise.<br /><br />How come efficiency is recognized as being optimal in everything except the human body? mikej26https://www.blogger.com/profile/04428379731454622909noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-22699494923876441302016-07-12T08:18:21.344-07:002016-07-12T08:18:21.344-07:00Reversing the study order is bound to be more expe...Reversing the study order is bound to be more expensive. It would take a week or two under ward conditions to replenish dieters glycogen to pre-ketosis state. <br /><br />The original sequence gave HFLC another advantage. The dieters were fully "carbo loaded" entering HFLC. It should have been a perfect HFLC storm...thhqhttps://www.blogger.com/profile/07256574635664867999noreply@blogger.comtag:blogger.com,1999:blog-1629175743855013102.post-57794769015333995752016-07-12T08:05:01.210-07:002016-07-12T08:05:01.210-07:00The more I look at the study design the more I lik...The more I look at the study design the more I like it. It's very aggressive using such a high sugar load in the high carb diet. The HC is thus a near-perfect SAD control. This is the diet that HFLC attacks and not optimized for best nutrients. The isocalorie part is good too. If HFLC has a metabolic advantage the fat should fall off. The design puts the major HFLC claims on the line.<br /><br />In using an aggressive HFLC approach to study design, the failure is as complete as the planned success would have been. If there is funding for a repeat I would leave the study the same but reverse the diet sequence to ketosis first, followed by some period to restore glycogen, then the high carb. thhqhttps://www.blogger.com/profile/07256574635664867999noreply@blogger.com