The #1 Cause of Obesity: Insulin

I just recently found this website (Swedish doctor promoting a low carb, high fat, real food diet) so some of this has probably been discussed here before but it's new to me and there's a terrific explanation (hypothesis?) of what's driving the obesity epidemic in the US and around the world.
This 3rd episode of “The Skinny on Obesity” may be the best short video on obesity I’ve seen. Not because dr Robert Lustig tells me something I didn’t already know, but because he explains it so crystal clear that a kid will understand. -Andreas Eenfeldt, MD
It's only 8 minutes:
http://www.dietdoctor.com/the-1-cause-of-obesity-insulin

If you like a little more science to go with your easy to understand videos there's also this page:
http://www.dietdoctor.com/science
«134

Replies

  • This is true but the jury is still out on whether or not saturated fat causes heart disease the second leading cause of death in America. A low fat plant based diet is the only diet proven to reverse heart disease.
    You have to choose heart disease or diabetes you cant win these days
  • AlabasterVerve
    AlabasterVerve Posts: 3,171 Member
    This is true but the jury is still out on whether or not saturated fat causes heart disease the second leading cause of death in America. A low fat plant based diet is the only diet proven to reverse heart disease.
    You have to choose heart disease or diabetes you cant win these days
    There's nothing supporting the theory that saturated fats cause heart disease that hasn't been discredited (that I'm aware of) and the Ornish diet I assume you're talking about was a low fat and low carb. Saturated fats are not bad for you!
  • AlabasterVerve
    AlabasterVerve Posts: 3,171 Member
    However, in healthy people, insulin only goes up in response to meals.
    But we're not talking about healthy people.

    I do appreciate the links but they don't do anything to disprove the theory. Or is there something specific I missed that you think would give me a better understanding of the science?
  • fawnfatale
    fawnfatale Posts: 9 Member
    I watched a video of Dr. Andreas Eenfeldt doing a presentation at AHS. I found it quite interesting, but to each their own. It's about 40 minutes long not including the Q & A at the end. I thought it was a well done presentation. Watch if you want, don't if you don't want. http://www.youtube.com/watch?v=FSeSTq-N4U4
  • AlabasterVerve
    AlabasterVerve Posts: 3,171 Member
    I saw that video too, it's what led me to his site. Thanks for posting the link, fawnfatale. :)
  • LesterBlackstone
    LesterBlackstone Posts: 291 Member
    Roughly a quarter of obese humans have normal circulating insulin and normal insulin sensitivity ("metabolically healthy" obese) (9).
    In Pima (Akimel O'odham) native Americans, one of the most obesity-prone populations in the world, and certain other populations, insulin resistance and higher insulin secretion consistently predict less body fat gain over time (10, 11, 12, 12a, 12b). This has not been observed in all populations, but the fact that it occurs in some casts further doubt on the idea that elevated insulin is a central contributor to fat gain.

    Researchers have been studying insulin's impact on food intake and body fatness for a long time, and among those who are the most intimately involved in the field, the idea that elevated insulin leads to body fat accumulation seemed rather unlikely by the late 1980s (13). Although biology is complex, and you can never be totally certain where scientific progress will lead, we have enough evidence at this point to say that this hypothesis is probably not correct. We now know that food intake is regulated by a complex 'symphony' of signals originating from the brain, fat tissue, the gastrointestinal tract and the pancreas, and insulin seems to play little or no role in this process on a meal-to-meal basis (14). In the long term, it may constrain food intake and body fat mass due to its actions in the brain, in a manner similar to leptin (although less potently).
  • AlabasterVerve
    AlabasterVerve Posts: 3,171 Member
    While I can agree that some things might not be 100% right but I think the theory is compelling and the "rather unlikely" and "it mays" of the passage you quoted don't do anything to disprove it rather show that there's probably more to it--not that it doesn't have any merit.

    I do appreciate the links highlighting the opposing point of view though. Thanks for sharing.
  • LesterBlackstone
    LesterBlackstone Posts: 291 Member
    While I can agree that some things might not be 100% right but I think the theory is compelling and the "rather unlikely" and "it mays" of the passage you quoted don't do anything to disprove it rather show that there's probably more to it--not that it doesn't have any merit.

    I do appreciate the links highlighting the opposing point of view though. Thanks for sharing.

    You realize that scientists NEVER speak in absolutes, right? Whenever you hear someone speaking in absolutes, you can promptly disregard everything they have to say.


    The insulin hypothesis was discarded by mainstream science over 30 years ago -- you just have a few clowns on the fringe still pimping this stuff.

    They just happen to make more noise in the mainstream media.
  • AlabasterVerve
    AlabasterVerve Posts: 3,171 Member
    I have little faith in mainstream science from 30 years ago--that's what got us into this mess in the first place. Is there an actual study that discredits this? Maybe Acg (I think that's his name) can link to something? He's seems pretty knowledgeable about the research out there.

    But whether the insulin hypothesis turns out to be a bunch of BS or pure genius does that invalidate the recommendation to eat a low carb, high fat diet? At the end of the day that's what I'm interested in.
  • fawnfatale
    fawnfatale Posts: 9 Member
    @Lesterblackstone

    It's funny that you mention 30 years ago, as that's about the time the 'obesity epidemic' began. If you have the time you should watch the link I posted. Even if you don't agree with it all, he does have some interesting things to say.
  • LesterBlackstone
    LesterBlackstone Posts: 291 Member
    I have little faith in mainstream science from 30 years ago--that's what got us in this mess in the first place. Is there an actual study that discredits this? Maybe Acg (I think that's his name) can link to something? He's seems pretty knowledgeable about the research out there.

    But whether the insulin hypothesis turns out to be a bunch of BS or pure genius does invalidate the recommendation to eat a low carb, high fat diet? At the end of the day that's what I'm interested in.

    Low carb diets work the exact same way that every other diet works - by creating a caloric deficit. If you find that you can adhere to them long term, then they're generally fine. But they aren't magic, and they're no more effective than low-fat, or moderate-carb, moderate-fat diets.
  • jfan175
    jfan175 Posts: 812 Member
    This is correct. The number one cause of obesity is eating more calories than you burn. The only way to reverse obesity is to eat fewer calories than you burn. There may be things that influence the number of calories you burn at rest,(i.e. thyroid issues) but the bottom line is that caloric excess is the major contributing factor. Eating a healthy, balanced diet of mostly unprocessed foods at a moderate deficit will do more for fat loss and insulin regulation than any deprivation or loading of certain macros.
  • AlabasterVerve
    AlabasterVerve Posts: 3,171 Member
    Low carb diets work the exact same way that every other diet works - by creating a caloric deficit. If you find that you can adhere to them long term, then they're generally fine. But they aren't magic, and they're no more effective than low-fat, or moderate-carb, moderate-fat diets.
    They don't work the same way--in just a few weeks I can tell you that. My appetite has decreased which causes me to eat less, of course, but that doesn't explain the why of it. I can also be hungry for the first time in years and have be just that--hunger--and not a need to eat every few hours to avoid feeling sick. That's just a personal anecdote after lowering my carbs for a few weeks but there's SOMETHING going on that has nothing to do with my will power or self control.

    You might have missed these studies as well from the second link I gave:

    RCTs showing significantly more weight loss with low carb diets

    Shai I, et al. Weight loss with a low-carbohydrate, mediterranean, or low-fat diet. N Engl J Med 2008;359(3);229–41.
    Gardner CD, et al. Comparison of the Atkins, Zone, Ornish, and learn Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women. The a to z Weight Loss Study: A Randomized Trial. JAMA. 2007;297:969–977.

    Brehm BJ, et al. A Randomized Trial Comparing a Very Low Carbohydrate Diet and a Calorie-Restricted Low Fat Diet on Body Weight and Cardiovascular Risk Factors in Healthy Women. J Clin Endocrinol Metab 2003;88:1617–1623.

    Samaha FF, et al. A Low-Carbohydrate as Compared with a Low-Fat Diet in Severe Obesity. N Engl J Med 2003;348:2074–81.

    Sondike SB, et al. Effects of a low-carbohydrate diet on weight loss and cardiovascular risk factor in overweight adolescents. J Pediatr. 2003 Mar;142(3):253–8.

    Aude YW, et al. The National Cholesterol Education Program Diet vs a Diet Lower in Carbohydrates and Higher in Protein and Monounsaturated Fat. A Randomized Trial. Arch Intern Med. 2004;164:2141–2146.

    Volek JS, et al. Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutrition & Metabolism 2004, 1:13.

    Yancy WS Jr, et al. A Low-Carbohydrate, Ketogenic Diet versus a Low-Fat Diet To Treat Obesity and Hyperlipidemia. A Randomized, Controlled Trial. Ann Intern Med. 2004;140:769–777.

    Nichols-Richardsson SM, et al. Perceived Hunger Is Lower and Weight Loss Is Greater in Overweight Premenopausal Women Consuming a Low-Carbohydrate/High- Protein vs High-Carbohydrate/Low-Fat Diet. J Am Diet Assoc. 2005;105:1433–1437.

    Krebs NF, et al. Efficacy and Safety of a High Protein, Low Carbohydrate Diet for Weight Loss in Severely Obese Adolescents. J Pediatr 2010;157:252-8.

    Summer SS, et al. Adiponectin Changes in Relation to the Macronutrient Composition of a Weight-Loss Diet. Obesity (Silver Spring). 2011 Mar 31. [Epub ahead of print]

    Halyburton AK, et al. Low- and high-carbohydrate weight-loss diets have similar effects on mood but not cognitive performance. Am J Clin Nutr 2007;86:580–7.

    Dyson PA, et al. A low-carbohydrate diet is more effective in reducing body weight than healthy eating in both diabetic and non-diabetic subjects. Diabet Med. 2007 Dec;24(12):1430-5.

    Keogh JB, et al. Effects of weight loss from a very-low-carbohydrate diet on endothelial function and markers of cardiovascular disease risk in subjects with abdominal obesity. Am J Clin Nutr 2008;87:567–76.

    Volek JS, et al. Carbohydrate Restriction has a More Favorable Impact on the Metabolic Syndrome than a Low Fat Diet. Lipids 2009;44:297–309.

    Daly ME, et al. Short-term effects of severe dietary carbohydrate-restriction advice in Type 2 diabetes–a randomized controlled trial. Diabet Med. 2006 Jan;23(1):15–20.

    Westman EC, et al. The effect of a low-carbohydrate, ketogenic diet versus a low- glycemic index diet on glycemic control in type 2 diabetes mellitus. Nutr. Metab (Lond.)2008 Dec 19;5:36.
  • LesterBlackstone
    LesterBlackstone Posts: 291 Member
    LOL

    How many of these have you actually read? Or did you just copy/paste from some carbophobe site.

    How many of them matched calories and protein? Metabolic ward studies (self reported data is ridiculously unreliable). Get back to me when you read and understand what the studies are saying.


    Since we're playing the cut/paste game, why not use these (just about as relevant to the conversation)

    Bailey T. The dummies guide to promoting wildlife conservation in the Middle East: telling tales of unicorns and ossifrages to save the hawk and leopard. J Avian Med Surg. 2011 Jun;25(2):136-43.

    Hortin GL. Of immunounreactive urinary albumin and unicorns. Am J Clin Pathol. 2008 Aug;130(2):314-5.

    O'Sullivan M. Unicorns or Tiger Woods: are lie detection experts myths or rarities? A response to on lie detection "wizards" by Bond and Uysal. Law Hum Behav. 2007 Feb;31(1):117-23.

    Frenking G, Krapp A. Unicorns in the world of chemical bonding models. J Comput Chem. 2007 Jan 15;28(1):15-24. Review.

    Sage WM, Kalyan DN. Horses or unicorns: can paying for performance make quality competition routine? J Health Polit Policy Law. 2006 Jun;31(3):531-56.

    Simon L. Research into the origins and characteristics of unicorns: mental illness as the unicorn. Ethical Hum Sci Serv. 2000 Fall-Winter;2(3):181-92.

    Askanas V, Engel WK. Unicorns, dragons, polymyositis, and other mythical beasts. Neurology. 2004 Jul 27;63(2):403-4; author reply 404.

    Hagan JC 3rd. Unicorns, obstetricians, neurosurgeons--three things hard to find in Missouri. Mo Med. 2004 Jan-Feb;101(1):4-5.

    Streiner DL. Unicorns do exist: a tutorial on "proving" the null hypothesis. Can J Psychiatry. 2003 Dec;48(11):756-61.

    Amato AA, Griggs RC. Unicorns, dragons, polymyositis, and other mythological beasts. Neurology. 2003 Aug 12;61(3):288-9.

    Howe EG. Unicorns, Carravaggio, and fetal surgery. J Clin Ethics. 2001 Winter;12(4):333-45.

    Ariew R. Leibniz on the unicorn and various other curiosities. Early Sci Med. 1998 Nov;3(4):267-88.

    Stahl FW. Unicorns revisited. Genetics. 1992 Dec;132(4):865-7.

    Foster PL. Directed mutation: between unicorns and goats. J Bacteriol. 1992 Mar;174(6):1711-6.

    Morreim EH. The law of nature and the law of the land: of horses, zebras, and unicorns. Pharos Alpha Omega Alpha Honor Med Soc. 1990 Spring;53(2):2-6.

    [No authors listed] Editorial: Why unicorns? Med J Aust. 1976 May 15;1(20):728-9.
  • yarwell
    yarwell Posts: 10,477 Member
    How many of them matched calories and protein? Metabolic ward studies (self reported data is ridiculously unreliable). Get back to me when you read and understand what the studies are saying.
    Show us a list of studies that meet your standards and show that low carb diets are worse please ? Seems to me they either come out better or the same,

    I don't see why calories and protein should be matched, if a low carb diet has more protein than a high carb diet that's part of the story - comparing A with B. Likewise if people can happily eat 1200 calories on a self selected low carb diet but are sawing their fingers off on 1600 calories of high carb diet is this not an argument in favour of the low carb diet as well ?

    I happen to agree that reasonably high protein and calorie control are important aspects, but if we're looking for a comparison between the **** people eat normally and something that will take weight off their overhanging gut we just need something that works, for whatever reason.

    I'm not convinced insulin is the cause of obesity, but it inhibits lipolysis so when trying to lose weight the less of it the better.
  • PaleoPath4Lyfe
    PaleoPath4Lyfe Posts: 3,161 Member
    This is true but the jury is still out on whether or not saturated fat causes heart disease the second leading cause of death in America. A low fat plant based diet is the only diet proven to reverse heart disease.
    You have to choose heart disease or diabetes you cant win these days
    There's nothing supporting the theory that saturated fats cause heart disease that hasn't been discredited (that I'm aware of) and the Ornish diet I assume you're talking about was a low fat and low carb. Saturated fats are not bad for you!

    Exactly. Saturated fats are needed so much for normal body function down to the cellular level.
  • PaleoPath4Lyfe
    PaleoPath4Lyfe Posts: 3,161 Member
    While I can agree that some things might not be 100% right but I think the theory is compelling and the "rather unlikely" and "it mays" of the passage you quoted don't do anything to disprove it rather show that there's probably more to it--not that it doesn't have any merit.

    I do appreciate the links highlighting the opposing point of view though. Thanks for sharing.

    You realize that scientists NEVER speak in absolutes, right? Whenever you hear someone speaking in absolutes, you can promptly disregard everything they have to say.


    The insulin hypothesis was discarded by mainstream science over 30 years ago -- you just have a few clowns on the fringe still pimping this stuff.

    They just happen to make more noise in the mainstream media.

    Of course it was ditched because that was the height of the low fat push and sugar was added to everything.........

    Where has that gotten us? Fat, sick and very unhealthy.
  • caraiselite
    caraiselite Posts: 2,631 Member
    low carb for liiiiife.

    http://i.imgur.com/lxfLV.jpg
  • wewon
    wewon Posts: 838 Member
    @Lesterblackstone

    It's funny that you mention 30 years ago, as that's about the time the 'obesity epidemic' began. If you have the time you should watch the link I posted. Even if you don't agree with it all, he does have some interesting things to say.

    LMAO!!!!

    Tooooooshay!!
  • tigersword
    tigersword Posts: 8,059 Member
    Did I hear someone say Lustig?

    I'll start with this. http://www.alanaragonblog.com/2010/01/29/the-bitter-truth-about-fructose-alarmism/

    Ok, now that that's out of the way. Insulin has pretty much nothing to do with obesity.

    Does insulin prevent lipolysis? No. Does it reduce lipolysis? Of course it does, you've just eaten. When you eat food, your body uses the food for energy first, and only goes back to relying on lipolysis after the food has been fully digested and utilized. Leptin (the hormone that signals satiety) has also been shown to limit lipolysis. As has every other hormone that has to do with satiety.

    Does insulin shuttle glucose directly to fat storage? NO. Absolutely not. Glucose is almost NEVER stored as fat. Insulin's primary job is to transport glucose to muscle cells and vital organs for normal body function. 87% of the fat in an adipose cell comes from lipids, not triglycerides.

    Insulin is a key hormone in muscle building and maintenance. It has well over 100 functions in the human body, fat storage is nowhere near the top of the list.

    And how do you care to explain protein eliciting high insulin responses? Protein and carbohydrates both spike insulin to similar levels when you eat. If insulin is what makes us fat, then protein must be just as bad as carbs.

    The entire argument is based on fear, and a hope that the person they are trying to convince has a lack of understanding of human biology. The insulin hypothesis just doesn't stand up to actual facts.

    As for low carb vs higher carb. They both cause weight loss due to a calorie deficit. Protein should always be constant, regardless of carb level. And then "weight loss" is a misleading term. Low carb diets lead to much higher losses of water weight, due to the reduction of stored glycogen in the muscles. Fat loss is identical, regardless of carb level.
  • suziecue66
    suziecue66 Posts: 1,312 Member
    low carb diets work initially but most folks can't comply for life with this diet lifestyle. Too many proponents of low carb overweight but still sing the praises of low carb. They are even testing blood ketones now - something called nutritional ketosis. Testing the urine for ketones is out. They are limiting carbs and going very low on protein now and really upping the fat. Protein is now another culprit for why they put weight back on or not losing weight. I can see a lot of muscle loss happening.
  • LesterBlackstone
    LesterBlackstone Posts: 291 Member
    How many of them matched calories and protein? Metabolic ward studies (self reported data is ridiculously unreliable). Get back to me when you read and understand what the studies are saying.
    Show us a list of studies that meet your standards and show that low carb diets are worse please ? Seems to me they either come out better or the same,


    In 7 of the 10 studies, there was no difference in resting or sleeping metabolic rate.33-39 When fat was substituted for carbohydrate (keeping protein matched), the 24-hour energy expenditure of the groups did not differ. In two studies that included a post- obese subgroup, 24-hour energy expenditure decreased 75–80 calories per day as a result of the higher fat intake. When the results of all 10 studies were averaged, there was zero difference in 24-hour energy expenditure between the high-carbohydrate and high-fat diets. AARR, June 2009

    28. Schoeller DA, Buchholz AC. Energetics of obesity and weight control: does diet composition matter? J Am Diet Assoc. 2005 May;105(5 Suppl 1):S24-8. [Medline]

    29. Schoeller DA, Buchholz AC. Is a calorie a calorie? Am J Clin Nutr. 2004 May;79(5):899S-906S. [Medline]

    30. Davy KP, et al. Regulation of macronutrient balance in healthy young and older men. Int J Obes Relat Metab Disord. 2001 Oct;25(10):1497-502. [Medline]

    31. Roy HJ, et al. Substrate oxidation and energy expenditure in athletes and nonathletes consuming isoenergetic high- and low- fat diets. Am J Clin Nutr. 1998 Mar;67(3):405-11. [Medline]

    32. Thomas CD, et al. Nutrient balance and energy expenditure during ad libitum feeding of high-fat and high-carbohydrate diets in humans. Am J Clin Nutr. 1992 May;55(5):934-42. [Medline]

    33. Hill JO, et al. Nutrient balance in humans: effects of diet composition. Am J Clin Nutr. 1991 Jul;54(1):10-7. [Medline]
    34. Rumpler WV, et al. Energy-intake restriction and diet- composition effects on energy expenditure in men. Am J Clin Nutr. 1991 Feb;53(2):430-6. [Medline]

    35. Lean ME, James WP. Metabolic effects of isoenergetic nutrient exchange over 24 hours in relation to obesity in women. Int J Obes. 1988;12(1):15-27. [Medline]

    36. Abbott WG, et al. Energy expenditure in humans: effects of dietary fat and carbohydrate. Am J Physiol. 1990 Feb;258(2 Pt 1):E347-51. [Medline]

    37. Yerboeket-van de Venne WP, Westerterp KR. Effects of dietary fat and carbohydrate exchange on human energy metabolism. Appetite. 1996 Jun;26(3):287-300. [Medline]

    38. Astrup A, et al. Failure to increase lipid oxidation in response to increasing dietary fat content in formerly obese women. Am J Physiol. 1994 Apr;266(4 Pt 1):E592-9. [Medline]

    39. Whitehead JM, McNeill G, Smith JS. The effect of protein intake on 24-h energy expenditure during energy restriction. Int J Obes Relat Metab Disord. 1996 Aug;20(8):727-32. [Medline]


    I don't see why calories and protein should be matched, if a low carb diet has more protein than a high carb diet that's part of the story - comparing A with B.

    If protein and calories are matched,, varying levels of carbohydrate and fat makee NO DIFFERENCE. If you want to point the finger at a single macronutrient, you can't vary all three and hope to come to any reasonable conclusion (although this is one of the preferred tricks by carbophobes).

    Likewise if people can happily eat 1200 calories on a self selected low carb diet but are sawing their fingers off on 1600 calories of high carb diet is this not an argument in favour of the low carb diet as well ?

    Individual and highly variable. And nothing to do with insulin.

    I happen to agree that reasonably high protein and calorie control are important aspects, but if we're looking for a comparison between the **** people eat normally and something that will take weight off their overhanging gut we just need something that works, for whatever reason.


    No we aren't. We're comparing diets. And low-carb diets are no more effective than any other.
    I'm not convinced insulin is the cause of obesity, but it inhibits lipolysis so when trying to lose weight the less of it the better.

    You forget that it also promotes protein synthesis and inhibits protein degradation.
  • AlabasterVerve
    AlabasterVerve Posts: 3,171 Member
    Show us a list of studies that meet your standards and show that low carb diets are worse please ? Seems to me they either come out better or the same,
    I looked at each of the studies you provided to disprove that and the only thing that stands out to me is "greater average weight losses (2.5 kg over 12 weeks) have been reported for low-carbohydrate diets" and "Further research on differences in the composition of weight loss and on the influence of satiety on compliance with energy-restricted diets is needed to explain the observed increase in weight loss with diets high in protein and/or low in carbohydrate."

    Admittedly, I don't understand a lot of what I'm reading but your studies seem to confirm that low carb diets ARE more effective.
    28. Schoeller DA, Buchholz AC. Energetics of obesity and weight control: does diet composition matter? J Am Diet Assoc. 2005 May;105(5 Suppl 1):S24-8. [Medline]
    Greater average weight losses (2.5 kg over 12 weeks) have been reported for low-carbohydrate diets (<90 g/day) compared with traditional low-fat (<25% of energy), hypocaloric diets, implying a 233 kcal/day greater energy deficit. It has therefore been suggested that a low-carbohydrate diet may provide a metabolic advantage (an increase in energy expenditure), resulting in a positive effect on weight loss and maintenance. However, a review of studies in which 24-hour energy expenditure was measured did not provide evidence to support a metabolic advantage of low-carbohydrate diets and showed little evidence of a metabolic advantage of high-protein (>25% of energy) diets. Nonetheless, diets high in protein, but either low or modest in carbohydrate, have resulted in greater weight losses than traditional low-fat diets.

    http://www.ncbi.nlm.nih.gov/pubmed/15867892
    29. Schoeller DA, Buchholz AC. Is a calorie a calorie? Am J Clin Nutr. 2004 May;79(5):899S-906S. [Medline]
    Further research on differences in the composition of weight loss and on the influence of satiety on compliance with energy-restricted diets is needed to explain the observed increase in weight loss with diets high in protein and/or low in carbohydrate.

    http://www.ajcn.org/content/79/5/899S.full
    30. Davy KP, et al. Regulation of macronutrient balance in healthy young and older men. Int J Obes Relat Metab Disord. 2001 Oct;25(10):1497-502. [Medline]
    To determine the influence of age on the ability to adjust macronutrient oxidation to changes in diet composition. Our hypothesis was that the ability to adjust macronutrient oxidation to changes in diet composition would be impaired with age. I didn't understand what that was saying but here's the link:

    http://www.unboundmedicine.com/evidence/ub/citation/11673772/Regulation_of_macronutrient_balance_in_healthy_young_and_older_men_
    31. Roy HJ, et al. Substrate oxidation and energy expenditure in athletes and nonathletes consuming isoenergetic high- and low- fat diets. Am J Clin Nutr. 1998 Mar;67(3):405-11. [Medline]
    The resoults from this study show that in healthy young men, fuel oxidation shifts both actuely and chromically to apporximate the macronutrient composition of the diet. There were no differences in any aspect of substrate balance in AT athletes, WT athletes, or NA men by group Again, I didn't understand it but I'm not sure that a study on three healthly, athletic men can tell us anything about what's happening is the obese.

    http://www.ajcn.org/content/67/3/405.full.pdf
    32. Thomas CD, et al. Nutrient balance and energy expenditure during ad libitum feeding of high-fat and high-carbohydrate diets in humans. Am J Clin Nutr. 1992 May;55(5):934-42. [Medline]
    To study the influence of diet composition on regulation of body weight, we fed 21 weight-stable subjects (11 lean, 10 obese) high-carbohydrate (HC) and high-fat (HF) diets for 1 wk each. Although diet composition was fixed, total energy intake was unrestricted. Subjects had a higher energy intake on the HF (11,039 +/- 2700 kJ/d) than on the HC (10,672 +/- 2617 kJ/d) diet (P less than 0.05), but energy expenditure was not different between diets. On day 7 of the HC diet, carbohydrate (CHO) oxidation was significantly related to CHO intake with the slope of the regression line 0.99, suggesting that overall CHO balance was near zero. However, the slope of the regression line was greater for obese than for lean subjects. On day 7 of the HF diet, fat oxidation was significantly related to fat intake but the slope of the line was 0.50, suggesting that overall fat balance was positive. However, this relationship was due entirely to lean subjects, with obese subjects showing no relationship between fat intake and oxidation. I'm not sure what the first part is really saying but is the last line saying that lean and obese subjects responded completely different?

    http://www.unboundmedicine.com/evidence/ub/citation/1570800/Nutrient_balance_and_energy_expenditure_during_ad_libitum_feeding_of_high_fat_and_high_carbohydrate_diets_in_humans_
    33. Hill JO, et al. Nutrient balance in humans: effects of diet composition. Am J Clin Nutr. 1991 Jul;54(1):10-7. [Medline]
    The purpose of this study was to examine the effect of alterations in diet composition on energy expenditure and nutrient balance in humans. Eight adults (three men, five women) ate a high-carbohydrate (60% of calories from carbohydrate) and a high-fat (60% of calories from fat) diet for 7 d each according to a randomized, crossover design. Six subjects were studied for an additional week on a mixed diet (45% of calories from fat). For each subject, total caloric intake was identical on all diets and was intended to provide the subject's maintenance energy requirements. All subjects spent days 3 and 7 of each week in a whole-room indirect calorimeter. Diet composition did not affect total daily energy expenditure but did affect daily nutrient oxidation by rapidly shifting substrate oxidation to more closely reflect the composition of the diet. These results show that diet composition can affect substrate oxidation without producing measurable effects on total energy expenditure. What's substrate oxidation?

    http://www.unboundmedicine.com/evidence/ub/citation/2058571/Nutrient_balance_in_humans:_effects_of_diet_composition_
    34. Rumpler WV, et al. Energy-intake restriction and diet- composition effects on energy expenditure in men. Am J Clin Nutr. 1991 Feb;53(2):430-6. [Medline]
    I couldn't find it.
    35. Lean ME, James WP. Metabolic effects of isoenergetic nutrient exchange over 24 hours in relation to obesity in women. Int J Obes. 1988;12(1):15-27. [Medline]
    Twenty-four hour whole body indirect calorimetry has been used to study the effects of feeding, during a sedentary test day, isoenergetic diets which varied in fat (3 or 40 per cent of total energy) and carbohydrate (82 or 45 per cent) content. Three groups of women were studied: lean, obese and 'post-obese' after slimming. Diets weren't compared at all.

    http://www.ncbi.nlm.nih.gov/pubmed/3360561
    36. Abbott WG, et al. Energy expenditure in humans: effects of dietary fat and carbohydrate. Am J Physiol. 1990 Feb;258(2 Pt 1):E347-51. [Medline]
    A high-dietary fat intake may be an important environmental factor leading to obesity in some people. The mechanism could be either a decrease in energy expenditure and/or an increase in caloric intake. To determine the relative importance of these mechanisms we measured 24-h energy expenditure in a whole body calorimeter in 14 nondiabetic subjects and in six subjects with non-insulin-dependent diabetes mellitus, eating isocaloric, weight-maintenance, high-fat, and high-carbohydrate diets. All subjects were Pima Indians. In nondiabetics, the mean total 24-h energy expenditure was similar (2,436 +/- 103 vs. 2,359 +/- 82 kcal/day) on high-fat and high-carbohydrate diets, respectively. The means for sleeping and resting metabolic rates, thermic effect of food, and spontaneous physical activity were unchanged. Similar results were obtained in the diabetic subjects. In summary, using a whole body calorimeter, we found no evidence of a decrease in 24-h energy expenditure on a high-fat diet compared with a high-carbohydrate diet.
    http://www.unboundmedicine.com/evidence/ub/citation/2305878/Energy_expenditure_in_humans:_effects_of_dietary_fat_and_carbohydrate_
    37. Yerboeket-van de Venne WP, Westerterp KR. Effects of dietary fat and carbohydrate exchange on human energy metabolism. Appetite. 1996 Jun;26(3):287-300. [Medline]
    Short-term effects of low-fat (10% fat energy), mixed (30% fat energy), and high-fat (50% fat energy) diets on 24-h energy expenditure, and on its components sleeping metabolic rate, diet induced thermogenesis and energy expenditure for physical activity were studied for 3 days using a respiration chamber in twelve normal-weight female volunteers classified as restrained or unrestrained eaters. There were no significant differences in any of the four measures between the restrained and unrestrained eating subjects on any of the diets. Within the group of restrained eaters, 24-h energy expenditure was significantly decreased during consumption of the mixed diet (8.21 +/- 0.21 MJ/d; p < 0.01) and tended to be decreased on the high-fat diet (8.22 +/- 0.25 MJ/d; p = 0.055), relative to the low-fat diet (8.58 +/- 0.21 MJ/d). Diet composition had no effect on 24-h energy expenditure in the women with unrestrained eating. The results suggest that a low-fat diet would be beneficial in the treatment of obesity, especially if subjects have a restrained type of eating behaviour. Where are the carbs?

    http://www.ncbi.nlm.nih.gov/pubmed/8800484
    38. Astrup A, et al. Failure to increase lipid oxidation in response to increasing dietary fat content in formerly obese women. Am J Physiol. 1994 Apr;266(4 Pt 1):E592-9. [Medline]
    Decreasing the dietary fat content increased 24-h EE in the postobese women (P = 0.02), whereas it was unaffected in the control group. Independent of energy balance, an increase in dietary fat content to 50% fat energy results in preferential fat storage, impaired suppression of carbohydrate oxidation, and reduction of 24-h EE in postobese women. Is that why low carb diets work so well--obese people have impaired carb oxidation?

    http://www.unboundmedicine.com/evidence/ub/citation/8178980/Failure_to_increase_lipid_oxidation_in_response_to_increasing_dietary_fat_content_in_formerly_obese_women_
    39. Whitehead JM, McNeill G, Smith JS. The effect of protein intake on 24-h energy expenditure during energy restriction. Int J Obes Relat Metab Disord. 1996 Aug;20(8):727-32. [Medline]
    CONCLUSIONS:
    Maintaining protein intake reduces the decrease in energy expenditure during energy restriction.

    http://www.ncbi.nlm.nih.gov/pubmed/8856395
  • mmapags
    mmapags Posts: 8,934 Member
    Did I hear someone say Lustig?

    I'll start with this. http://www.alanaragonblog.com/2010/01/29/the-bitter-truth-about-fructose-alarmism/

    Ok, now that that's out of the way. Insulin has pretty much nothing to do with obesity.

    Does insulin prevent lipolysis? No. Does it reduce lipolysis? Of course it does, you've just eaten. When you eat food, your body uses the food for energy first, and only goes back to relying on lipolysis after the food has been fully digested and utilized. Leptin (the hormone that signals satiety) has also been shown to limit lipolysis. As has every other hormone that has to do with satiety.

    Does insulin shuttle glucose directly to fat storage? NO. Absolutely not. Glucose is almost NEVER stored as fat. Insulin's primary job is to transport glucose to muscle cells and vital organs for normal body function. 87% of the fat in an adipose cell comes from lipids, not triglycerides.

    Insulin is a key hormone in muscle building and maintenance. It has well over 100 functions in the human body, fat storage is nowhere near the top of the list.

    And how do you care to explain protein eliciting high insulin responses? Protein and carbohydrates both spike insulin to similar levels when you eat. If insulin is what makes us fat, then protein must be just as bad as carbs.

    The entire argument is based on fear, and a hope that the person they are trying to convince has a lack of understanding of human biology. The insulin hypothesis just doesn't stand up to actual facts.

    As for low carb vs higher carb. They both cause weight loss due to a calorie deficit. Protein should always be constant, regardless of carb level. And then "weight loss" is a misleading term. Low carb diets lead to much higher losses of water weight, due to the reduction of stored glycogen in the muscles. Fat loss is identical, regardless of carb level.

    This^^ The whole post.
  • Sarauk2sf
    Sarauk2sf Posts: 28,072 Member
    Tagging for further reading on the unicorn studies cited.
  • mmapags
    mmapags Posts: 8,934 Member
    Tagging for further reading on the unicorn studies cited.

    ROFL!
  • taunto
    taunto Posts: 6,420 Member
    The #1 cause of obesity is that you're sitting on your butt on the internet or watching TV when we could be outside enjoying the beautiful weather
  • usmcmp
    usmcmp Posts: 21,219 Member
    gfjAd.png
  • LesterBlackstone
    LesterBlackstone Posts: 291 Member
    Some key phrases extracted for clarity:

    a review of studies in which 24-hour energy expenditure was measured did not provide evidence to support a metabolic advantage of low-carbohydrate diets

    There were no differences in any aspect of substrate balance in AT athletes, WT athletes, or NA men by group

    obese subjects showing no relationship between fat intake and oxidation.

    These results show that diet composition can affect substrate oxidation without producing measurable effects on total energy expenditure.

    no evidence of a decrease in 24-h energy expenditure on a high-fat diet compared with a high-carbohydrate diet.

    Diet composition had no effect on 24-h energy expenditure in the women with unrestrained eating.





    Bottom line: varying carbs and fat have NO effect on fat loss (given matched calories and protein). None. Thus the insulin hypothesis is unsupported.

    Like I said before, there's nothing wrong with low-carb diets (if you can adhere to them). Some find them more satiating. But they aren't magic and they don't allow you to violate the energy balance equation.

    Cutting carbs is optional. It's neither a necessary nor a sufficient condition for fat loss. Any difference in weight loss between low-carb and higher carb intake is strictly due to water retention (glycogen storage).