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Electronic letters to:
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Electronic letters published:
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Very-low-carbohydrate diets and preservation of muscle mass
Tackling the other side of the equation.
Banting Would Laugh In Your Face
Canada's Food Guide lacks evidence - especially for weight control
If Lavoisier could still be with us!
SLIMMING DOWN ON CALORIES WOULD JUST BE FINE FOR OBESITY CONTROL
Living Off The Fat Of The Land
Strychar´s review on weight loss diets: A failure of peer-review
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Anssi H Manninen Advanced Research Press
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sportsnutrition{at}luukku.com Anssi H Manninen
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For a more detailed review on very-low-carbohydrate diets and preservation of muscle mass, see my paper published (today) in Nutrition & Metabolism: http://www.nutritionandmetabolism.com/content/pdf/1743-7075-3-9.pdf Nevertheless, I would like to thank Dr. Strychar for her timely review. Conflict of Interest:None declared |
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Richard G Fiddian-Green, N/A None
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richardfg{at}hotmail.com Richard G Fiddian-Green
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Weight loss is a function not only of intake but also of nutrient utilization which is firstly to support ATP resynthesis. ATP resynthesis is achieved by a combination of anaerobic glycolysis and oxidative phosphorylation. As much as twenty times more nutrient may be needed to generate ATP by the former as compared with the latter, the decrease in efficiency of ATP resynthesis being matched and even exceeded by an accompanying increase in temperature. In malignant cachexia, for example, the proportion of ATP being replenished by anaerobic glycolysis would seem to be excessively large. The potential for achieving weight loss and more importantly maintaining weight reduction by shifting the balance between anaerobic glycolysis and oxidative phosporylation to anaerobic glycolysis could be huge. If so how might this be achieved? By sterotactic modulation of body temperature and/or pH (1)? There should be absolutely no problem with compliance as there might be with injections of PYY and oxyntomodulin as Professor Bloom has proposed (2). The risk associated with the invasive technique should even be very much smaller than those associated with morbid obesity and the metabolic syndrome. 1. Richard G Fiddian-Green Stereotactic modulation of intracerbral energetics http://www.jnnp.com/cgi/eletters/75/7/1019#180, 21 Jun 2004 2. www.imperialinnovations.co.uk/ news/news2004/innovation04_09_04_Thiakis.pdf |
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Dr. Herbert H. Nehrlich, Bribie Island, Australia Private Practice
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drhhnehrlich{at}westnet.com.au Dr. Herbert H. Nehrlich
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Maxime St-Onge's statement may make her some friends but what she says borders on poppycock. The notion that energy in equals energy out presupposes that the body treats macronutrients equally. Yes, exact numbers have been assigned to carbohydrates, fats and proteins and it is widely known that a reduction in fat intake is the single most important step the overweight person can take in order to slim down. As a bonus (s)he will also experience a new feedom from certain cancers and his cholesterol will be more politically correct. It is difficult to think of an unbiased person in science who would believe this. Banting was one of the first who not only believed in the effect of "re-arranging" macronutrients, he also proved it in his one person experiment.Millions have followed successfully. We cannot simply take the view that one must reduce calories in order to get slim. That would mean a denial of the existence of the "thrifty gene" which more often than not jeopardizes the best thought out slimming regimen. North America has been told for decades to reduce fat intake and rely on carbohydrates. As a result of this pathetically dim-witted advice visitors to the region are now more and more forced to use their wide- angle lenses to capture images of the locals. Two thirds of Americans (and Canadians I presume) are real fat. Most of them no doubt are eating low fat. As to Maxime's comment on what our ancestors ate, methinks a bit of research would change her mind on what she now appears to believe. As we all know, the chain length of fatty acids determines how they are processed and what energy they contribute. And it is also well known that the master key to fat storage is the hormone insulin. Reduce the production of insulin by the pancreas and you will reduce fat storage. And you do that by sending the signal that there will be no carbohydrates incoming. That's the secret and it would in my eyes invalidate the view still held by so many that a calory is a calory is a calory. Conflict of Interest:None declared |
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Dr. Yoni Freedhoff, 575 West Hunt Club, Suite 100 Ottawa ON K2G5W5 Bariatric Medical Institute
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drfreedhoff{at}bmimedical.ca Dr. Yoni Freedhoff
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It is truly sad that Canada's Food Guide is simply taken as the nutritional gospel in Canada. Health Canada's highly suspect and unethical conflict of interest in overtly inviting the food industry to sit on the board of advisors1 for the creation of the Food Guide and for the food industry to be formally invited as "stakeholders"2, along with the Guide's glaring omissions of evidence-based research supporting the minimization of refined carbohydrates, increasing poly-unsaturated fats and controlling calories, make Canada's Food Guide a nutritional lightweight in the ring of healthy diets. However to go so far as to suggest that it is a good choice for those considering weight loss is simply ludicrous.Category A evidence as presented by the NHLBI's Evidence Report on the treatment of obesity state that "low calorie diets are recommended for weight loss in overweight and obese persons"3. A low-calorie diet by definition contains less than 1,500 calories daily. By Health Canada's own reckoning following the Food Guide perfectly will lead to the consumption of between 1800-3200 calories4 daily. But unfortunately, the calories do not stop there. Not including in Canada's Food Guide is the "other" category of food. Other foods include foods with added fats and sugars, and according to a 2001 study in Canadian Journal of Dietetic Practice Research, 25% of energy and fat intake for all age and gender groups come from the other category5. Therefore following Canada's Food Guide and consuming an average quantity of other foods will likely ultimately lead patients to consume 2,250-4,000 calories daily and that also assumes that the patients following the Food Guide actually take the time to learn about portion sizes and weigh and measures their dietary choices.Canada's Food Guide is certainly not a low-calorie-diet, and even if followed perfectly will likely lead to weight gain in the vast majority of patients. I would go so far as to describe Canada's Food Guide as obesigenic and I cannot help but speculate that part of the reason that it recommends the consumption of so much food is Health Canada's bizarre inclusion of the food industry in its creation. If Canadian physicians read Dr. Strychar's conclusion that Canada's Food Guide is a safe choice for a weight-loss regimen and consequently recommend it to their well-intentioned overweight and obese patients, they had better be prepared to counsel them when their efforts to lose weight ultimately fail.Dr. Yoni Freedhoff, MD CCFP Dip ABBM Specialist in Obesity Medicine Medical Director, Bariatric Medical Institute REFERENCES 1. Health Canada, Food Guide Advisory Committee 2005. Available: http://www.hc-sc.gc.ca/fn-an/food-guide-aliment/revision/fg_advis_com-com_cons_ga_e.html 2. Health Canada, January 20th, 2004 Invited Participant List. Available: http://www.hc-sc.gc.ca/fn-an/food-guide-aliment/review-examen/meet-reunion/review_list_participants-examen_liste_participants_e.html 3. National Heart, Lung and Blood Institute. Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults. The evidence report. NIH Publication No. 98-4083;1998 September 4. Health Canada, Using the Food Guide. Available: http://www.hc-sc.gc.ca/fn-an/food-guide-aliment/res/using_food_guide-servir_guide_alimentaire_e.html 5. Starkey LJ, Johnson-Down L, Gray-Donald K. Food habits of Canadians: Comparison of intakes in adults and adolescents to Canada's Food Guide to healthy eating. Can. J. Diet Pract. Res. 2001;Summer,62(2):61-69 | |||
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Maxime St-Onge, 780 St-Rémi loft 51, montréal, québec, canada, H4C 3H2 Université de Montréal
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maxime.st-onge{at}sympatico.ca Maxime St-Onge
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It is hard to believe that the notion that certain combinaison of macronutriments could positively influence the energy equilibrium beside their respective energy contribution. It is well known that any weight gain must be generated by an energy surplus and that weight loss must inevitably be generated through an energy deficit. The erronous notion that improper macronutriments repartition could increase body weight without a positive energy balance (1-3) is again misleading to many healthcare professional and should not be propagated without proper scientific support. The historical reference to human previous eating habit is also to often wrong. Most of the diet of many human tribes (hunter or gatherer) consisted of carbohydrated and nothing let us believe that previous human civilizations followed high fat and/or high protein diet for prolonged period of time (4). Practicaly every animal is subject to the rule of energy equilibrium (5) and nothing can lead the scientific community to believe otherwise. Weight gain has to be the result of an energy intake superior to energy expenditure; quality of food having little effect on the sole aspect of weight gain. The main difference between our ancestor and our civilization is simply a reduction in energy expenditure synchronized with an increase in food availability. Maxime St-Onge 1. Roberts, S.B. and G.E. Dallal, Effects of age on energy balance. Am J Clin Nutr, 1998. 68(4): p. 975S-979S. 2. Westerterp, K.R., Alterations in energy balance with exercise. Am J Clin Nutr, 1998. 68(4): p. 970S-974S. 3. van Baak, M.A., Physical activity and energy balance. Public Health Nutr, 1999. 2(3A): p. 335-9. 4. Walker, A.R., B.F. Walker, and F. Adam, Nutrition, diet, physical activity, smoking, and longevity: from primitive hunter-gatherer to present passive consumer--how far can we go? Nutrition, 2003. 19(2): p. 169-73. 5. Hargrove, J.L., Adipose energy stores, physical work, and the metabolic syndrome: lessons from hummingbirds. Nutr J, 2005. 4(1): p. 36. |
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Dr. Rajesh Chauhan Consultant, Family Medicine & Communicable Diseases
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drchauhanrajesh{at}yahoo.com Dr. Rajesh Chauhan
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Dear Editor, The debates on obesity control are just not coming to logical conclusions, thereby providing enough time and opportunity for obesity to continue widening its base. Easy availability and access to ‘calories’, along with cutback in catabolism is perhaps the root cause. If that is so, then maybe the line of control and management of obesity would seem simple. As a prerequisite, a strong willpower has to be generated and sustained by every patient wanting to check out of the ‘guild’, where he/she is just ‘stuck’. Peers must be actively involved for moral support and lasting results. A few patients have benefited from my simple trick of allowing them unrestricted course of meals. However, they must first have a large helping of veg salad and fruits followed by a pint of liberally diluted buttermilk, before settling down to the 'real business'. They are also advised against snacks taken in-between the meals. Lightly salted and peppered buttermilk can again be a good substitute for the cravings of snacks. Simultaneously, starting with light exercises like a simple walk, the rate, and extent of catabolism is gradually enhanced. Slimming down on calories rather, is essential, and would be just fine for obesity control. Once a motivated patient has been able to follow the advice for 48 hours, which is the most difficult period, the rest of the sailing is real smooth with this cheap, unrestricted, unstructured, tasty, and tested modality, which seems to work. With warm regards. Conflict of Interest:None declared |
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Dr. Herbert H. Nehrlich Private Practice
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drhhnehrlich{at}westnet.com.au Dr. Herbert H. Nehrlich
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A catchy title? The paper is fairly thorough but let down by the fact that old knowledge is re-hashed and the myth of the effectiveness of low caloric dieting is propagated. Since Banting, it has been known that low carbohydrate dieting is what man naturally is programmed to live by, carbohydrates just weren't available en masse before the advent of agriculture. Since it takes insulin to "open" the cells for fat storage it stands to reason that anything that will reduce insulin output ought to reduce fat storage and thus, obesity. The great experiment of North America where several decades of low caloric/high carbohydrate dieting have produced a significant increase in obesity should show us that this method is the wrong row to hoe. Although the author seems to be diplomatic about the low carb diet, he cites the presence of saturated fats in diets such as the Atkins' Regimen as (Heart Association sanctioned) reason not to use it. Today, there is so much evidence that the diet heart hypothesis which puts the blame for our modern heart disease deluge on the bogeyman cholesterol and his first cousins, the saturated fats, is a colossal fallacy. Nothing much could be further from the truth although I do realise that the jury has been delayed due to monetary interests. If I were in charge of tackling the obesity problem I would recommend that people eat traditional foods that have undergone minimal processing, that at least 60 % of the energy needs come from (mostly animal) fats and that the other macronutrients would take care of themselves. Most low carb diets have their idiosyncrasies (to justify yet another book methinks) and all low caloric-high carbohydrate diets make people fat. Conflict of Interest:None declared |
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Anssi H Manninen Advanced Research Press, Inc.
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sportsnutrition{at}luukku.com Anssi H Manninen
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In my view, the recent review by Strych contains some incorrect and biased statements. For example, according to the author, "[During very-low -carbohydrate intake] The body depletes its glycogen stores, and gluconeogenesis is induced, whereby lean tissue is used to produce glucose as an energy source for the brain." This statement is clearly fallacious. True, animals share the metabolic deficiency of the total (or almost total) inability to convert fatty acids to glucose. So, the primary source for a substrate for gluconeogenesis is amino acid, with some help from glycerol from fat tissue triglycerides. However, when the rate of mobilization of fatty acids from fat tissue is accelerated, as, for example, during a very-low-carb diet, the liver produces ketone bodies. The liver can’t utilize ketone bodies and thus, they flow from the liver to extra-hepatic tissues (e.g., brain, muscle) for use as a fuel. Simply stated, ketone body metabolism by the brain displaces glucose utilization and thus spares muscle mass. In other words, the brain derives energy from storage fat during a very-low-carb diet. Numerous studies indicate that low-carbohydrate/high-protein diet is, if anything, protective againts muscle mass loss during energy restriction; see my recent paper published in Journal of the International Society of Sports Nutrition; http://www.sportsnutritionsociety.org/site/pdf/Manninen-JISSN-1-2-21-26- 05.pdf. Sincerely, Anssi Manninen, M.H.S.(sportsmed) Senior Sciece Editor Advanced Research Press, Inc. PS. For more information on human nutrition and metabolism, visit www.nutritionandmetabolism.com Conflict of Interest:None declared |
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