Low fat beats low carb diet - can we trust the experts?
in [Nutrition]
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From: Taka on 5 Aug 2008 02:32 The following study says so: http://hyper.ahajournals.org/cgi/content/abstract/51/2/376 and is advertised on the LEF site: Low fat beats low carb in heart disease prevention The February, 2008 issue of Hypertension published an article which concluded that low fat diets were better than low carbohydrate diets to prevent cardiovascular disease. Although both diets have their adherents in regard to their weight- loss results, concern exists that the higher fat content of low carbohydrate diets could increase cardiovascular disease risk. For the current investigation, David D. Gutterman, MD of the Medical College of Wisconsin in Milwaukee and his colleagues assigned 20 obese participants to a low fat diet, providing 30 percent of its calories in the form of fat, or a low carbohydrate diet for six weeks. Brachial flow-mediated dilation, which evaluates endothelial function, was measured at the beginning of the study, during the second week, and at the study's conclusion. Blood pressure, weight, and cholesterol were measured throughout the trial. Although all subjects experienced improvements in weight and blood pressure, the percentage of arterial flow-mediated dilation declined among those who followed the low carbohydrate diet, while significantly improving in the low fat group. We observed a reduction in brachial artery flow-mediated dilation after six weeks of weight loss on a low-carbohydrate, Atkins-style diet, stated Dr. Gutterman. The higher fat content of a low-carbohydrate diet may put dieters at an increased risk of atherosclerosis because low-carbohydrate diets often reduce protection of the endothelium, the thin layer of cells that line the blood vessels of the circulatory system. The reduced production from the endothelium of nitric oxide, a specific chemical, puts the vessel at higher risk of abnormal thickening, greater clotting potential, and cholesterol deposition, all part of the atherosclerosis process. An addition risk incurred by low-carbohydrate diets is their reduced levels of folic acid, a B vitamin that helps lower homocysteine. The composition of diet may be as important as the degree of weight loss in determining the effect of dietary interventions on vascular health, Dr. Gutterman observed. ----------------------------- In the abovementioned study they don't say which fat was used but I am pretty sure it was a PUFA rich one. They would certainly account for the saturated fat to support the current policy of demonizing it if it were used. So I interpret this study as saying that dietary PUFAs are worst that dietary carbohydrates. Other funny statements from the LEF site: ( http://www.lef.org/protocols/cancer/pancreatic_01.htm ) " Risk Factors for Pancreatic Cancer Diet: excess calorie intake; high intake of SATURATED FATS and oils, INCLUDING OMEGA-6 fatty acids, meat, and dairy products; and high intake of fried foods, carbohydrates, cholesterol, salt, nitrites from animal products, and nitrosamines (Coss A et al 2004)." so they nearly classify Omega-6 as saturated fat here ... " Olive Oil. Olive oil contains several antioxidants and a protective fat called oleic acid that diminish the risk of cell damage (Owen RW et al 2004) by scavenging free radicals (Alarcon de la Lastra C et al 2001)." so now we promoted MUFAs to the category of protective free radical scavenging antioxidants, well so much a single double bond can do! Such confusing statements just distract people from the real problem which of course is the excess of dietary Omega-6 and lure them to buying different polyphenol rich supplements and Omega-3 fatty acids to counteract the arachidonic acid metabolism. Taka
From: Matti Narkia on 5 Aug 2008 12:32 Taka wrote: > The following study says so: > > http://hyper.ahajournals.org/cgi/content/abstract/51/2/376 > The full reference is Phillips SA, Jurva JW, Syed AQ, Syed AQ, Kulinski JP, Pleuss J, Hoffmann RG, Gutterman DD. Benefit of low-fat over low-carbohydrate diet on endothelial health in obesity. Hypertension. 2008 Feb;51(2):376-82. Epub 2008 Jan 14. PMID: 18195164 doi: 10.1161/HYPERTENSIONAHA.107.101824 <http://hyper.ahajournals.org/cgi/content/full/51/2/376> (full text is freely available) > and is advertised on the LEF site: > > Low fat beats low carb in heart disease prevention > > The February, 2008 issue of Hypertension published an article which > concluded that low fat diets were better than low carbohydrate diets > to prevent cardiovascular disease. > > Although both diets have their adherents in regard to their weight- > loss results, concern exists that the higher fat content of low > carbohydrate diets could increase cardiovascular disease risk. For the > current investigation, David D. Gutterman, MD of the Medical College > of Wisconsin in Milwaukee and his colleagues assigned 20 obese > participants to a low fat diet, providing 30 percent of its calories > in the form of fat, or a low carbohydrate diet for six weeks. Brachial > flow-mediated dilation, which evaluates endothelial function, was > measured at the beginning of the study, during the second week, and at > the study's conclusion. Blood pressure, weight, and cholesterol were > measured throughout the trial. > > Although all subjects experienced improvements in weight and blood > pressure, the percentage of arterial flow-mediated dilation declined > among those who followed the low carbohydrate diet, while > significantly improving in the low fat group. [snip] > > An addition risk incurred by low-carbohydrate diets is their reduced > levels of folic acid, a B vitamin that helps lower homocysteine. �The > composition of diet may be as important as the degree of weight loss > in determining the effect of dietary interventions on vascular > health,� Dr. Gutterman observed. > Low-carbohydrate diets don't need be low in folate. In fact the best sources of folate are organ meats such as liver and kidney, see <http://www.fineli.fi/topfoods.php?compid=2273&fuclass=all&specdiet=none&items=200&from=top&portion=100g&lang=en> <http://tinyurl.com/6qaadp> Ok, liver may not be recommendable for continuous use because of its high preformed vitamin A content and potentially high content of environmental toxins, and kidney may not please everyone's taste buds (although I found it delicious, when I still ate meat), but there are many other low-carbohydrate food items, which have high folate content, for example soy beans and various soy products such as soy flour and soy protein, egg yolks, asparagus, parsley, beetroot, green beans, kale, broccoli, Brussels sprouts, parsnip, and cauliflower. So if in this study the low-carbohydrate diet had low folate content, that sounds almost like intentional or alternatively shows ignorance, stupidity or/and bad planning. Many vegetables and berries are low-carbohydrate and contain plenty of antioxidants, which protect endothelium. Nuts are also low-carbohydrate and provide plenty of L-arginine, the only precursor for nitric oxide needed by endothelium for dilation. If this study did not include enough of these into the low-carbohydrate diet, that is bad planning (or intentional) and may have made results worse. > ----------------------------- > > In the abovementioned study they don't say which fat was used but I am > pretty sure it was a PUFA rich one. Although you are pretty sure, you don't present any proof for that, and neither does the full text of the study. Perhaps we should thus just ignore this comment by you. > They would certainly account for > the saturated fat to support the current policy of demonizing it if it > were used. So I interpret this study as saying that dietary PUFAs are > worst that dietary carbohydrates. > There is no evidence supporting your interpretation, so may be again it's best to ignore it. [snip] > " Olive Oil. Olive oil contains several antioxidants and a protective > fat called oleic acid that diminish the risk of cell damage (Owen RW > et al 2004) by scavenging free radicals (Alarcon de la Lastra C et al > 2001)." > > so now we promoted MUFAs to the category of protective free radical > scavenging antioxidants, well so much a single double bond can do! > MUFA is fairly stable and therefore possibly not very prone to lipid peroxidation or other harmful changes, but its not the antioxidant meant in above citation. Olive oil's antioxidants are its phenolic compounds such as tyrosol, hydroxytyrosol, oleocanthal and oleuropein. Olive oil also contains vitamin E. See Olive oil, extra virgin <http://whfoods.org/genpage.php?tname=foodspice&dbid=132> Olive oil <http://en.wikipedia.org/wiki/Olive_oil> Waterman E, Lockwood B. Active components and clinical applications of olive oil. Altern Med Rev. 2007 Dec;12(4):331-42. Review. PMID: 18069902 <http://www.thorne.com/altmedrev/.fulltext/12/4/331.pdf> Gimeno E, de la Torre-Carbot K, Lamuela-Ravent�s RM, Castellote AI, Fit� M, de la Torre R, Covas MI, L�pez-Sabater MC. Changes in the phenolic content of low density lipoprotein after olive oil consumption in men. A randomized crossover controlled trial. Br J Nutr. 2007 Dec;98(6):1243-50. Epub 2007 Jul 9. PMID: 17617938 doi:10.1017/S0007114507778698 <http://journals.cambridge.org/action/displayAbstract?aid=1451752> Fit� M, Cladellas M, de la Torre R, Mart� J, Mu�oz D, Schr�der H, Alc�ntara M, Pujadas-Bastardes M, Marrugat J, L�pez-Sabater MC, Bruguera J, Covas MI; the members of the SOLOS Investigators. Anti-inflammatory effect of virgin olive oil in stable coronary disease patients: a randomized, crossover, controlled trial. Eur J Clin Nutr. 2008 Apr;62(4):570-574. Epub 2007 Mar 21. PMID: 17375118 doi:10.1038/sj.ejcn.1602724 <http://www.nature.com/ejcn/journal/v62/n4/abs/1602724a.html> Weinbrenner T, Fito M, de la Torre R, Saez GT, Rijken P, Tormos C, Coolen S, Albaladejo MF, Abanades S, Schroder H, Marrugat J, Covas MI. Olive oils high in phenolic compounds modulate oxidative/antioxidative status in men. J Nutr. 2004 Sep;134(9):2314-21. PMID: 15333722 <http://jn.nutrition.org/cgi/content/full/134/9/2314> Fito M, de la Torre R, Covas MI. ' Olive oil and oxidative stress. Mol Nutr Food Res. 2007 Sep 19; [Epub ahead of print] PMID: 17879994 <http://www3.interscience.wiley.com/journal/116320533/abstract> <http://www3.interscience.wiley.com/cgi-bin/fulltext/116320533/PDFSTART> (free full text PDF file) Covas MI, Nyyssonen K, Poulsen HE, Kaikkonen J, Zunft HJ, Kiesewetter H, Gaddi A, de la Torre R, Mursu J, Baumler H, Nascetti S, Salonen JT, Fito M, Virtanen J, Marrugat J, EUROLIVE Study Group. The effect of polyphenols in olive oil on heart disease risk factors: a randomized trial. Ann Intern Med. 2006 Sep 5;145(5):333-41. Summary for patients in: Ann Intern Med. 2006 Sep 5;145(5):I53. PMID: 16954359 <http://www.annals.org/cgi/reprint/145/5/333.pdf> (free full text PDF) Dell'Agli M, Maschi O, Galli GV, Fagnani R, Dal Cero E, Caruso D, Bosisio E. Inhibition of platelet aggregation by olive oil phenols via cAMP-phosphodiesterase. Br J Nutr. 2008 May;99(5):945-51. Epub 2007 Oct 11. PMID: 17927845 doi:10.1017/S0007114507837470 <http://journals.cambridge.org/action/displayAbstract?aid=1830968> -- Matti Narkia http://ma.gnolia.com/groups/Nutrition
From: Matti Narkia on 5 Aug 2008 12:44 Matti Narkia wrote: > Taka wrote: > >> The following study says so: >> >> http://hyper.ahajournals.org/cgi/content/abstract/51/2/376 >> > The full reference is > > Phillips SA, Jurva JW, Syed AQ, Syed AQ, Kulinski JP, Pleuss J, > Hoffmann RG, Gutterman DD. > Benefit of low-fat over low-carbohydrate diet on endothelial > health in obesity. > Hypertension. 2008 Feb;51(2):376-82. Epub 2008 Jan 14. > PMID: 18195164 > doi: 10.1161/HYPERTENSIONAHA.107.101824 > <http://hyper.ahajournals.org/cgi/content/full/51/2/376> > (full text is freely available) > >> and is advertised on the LEF site: >> >> Low fat beats low carb in heart disease prevention >> >> The February, 2008 issue of Hypertension published an article which >> concluded that low fat diets were better than low carbohydrate diets >> to prevent cardiovascular disease. >> >> Although both diets have their adherents in regard to their weight- >> loss results, concern exists that the higher fat content of low >> carbohydrate diets could increase cardiovascular disease risk. For the >> current investigation, David D. Gutterman, MD of the Medical College >> of Wisconsin in Milwaukee and his colleagues assigned 20 obese >> participants to a low fat diet, providing 30 percent of its calories >> in the form of fat, or a low carbohydrate diet for six weeks. Brachial >> flow-mediated dilation, which evaluates endothelial function, was >> measured at the beginning of the study, during the second week, and at >> the study's conclusion. Blood pressure, weight, and cholesterol were >> measured throughout the trial. >> >> Although all subjects experienced improvements in weight and blood >> pressure, the percentage of arterial flow-mediated dilation declined >> among those who followed the low carbohydrate diet, while >> significantly improving in the low fat group. > > [snip] >> >> An addition risk incurred by low-carbohydrate diets is their reduced >> levels of folic acid, a B vitamin that helps lower homocysteine. �The >> composition of diet may be as important as the degree of weight loss >> in determining the effect of dietary interventions on vascular >> health,� Dr. Gutterman observed. >> > Low-carbohydrate diets don't need be low in folate. In fact the best > sources of folate are organ meats such as liver and kidney, see > > <http://www.fineli.fi/topfoods.php?compid=2273&fuclass=all&specdiet=none&items=200&from=top&portion=100g&lang=en> > > <http://tinyurl.com/6qaadp> > > Ok, liver may not be recommendable for continuous use because of its > high preformed vitamin A content and potentially high content of > environmental toxins, and kidney may not please everyone's taste buds > (although I found it delicious, when I still ate meat), but > there are many other low-carbohydrate food items, which have high > folate content, for example soy beans and various soy products such as > soy flour and soy protein, egg yolks, asparagus, parsley, beetroot, > green beans, kale, broccoli, Brussels sprouts, parsnip, and > cauliflower. So if in this study the low-carbohydrate diet had low > folate content, that sounds almost like intentional or alternatively > shows ignorance, stupidity or/and bad planning. > > Many vegetables and berries are low-carbohydrate and contain plenty > of antioxidants, which protect endothelium. Nuts are also > low-carbohydrate and provide plenty of L-arginine, the only precursor > for nitric oxide needed by endothelium for dilation. If this study did > not include enough of these into the low-carbohydrate diet, that is bad > planning (or intentional) and may have made results worse. > In the discussion chapter of the study it's mentioned that LC group got more L-arginine than LF group, so perhaps that was not a problem, but I still would like know why the folate content was low in LC group and what and how much low-carbohydrate vegetables and berries LC group got. -- Matti Narkia http://ma.gnolia.com/groups/Nutrition
From: Matti Narkia on 5 Aug 2008 13:50 Matti Narkia wrote: > Matti Narkia wrote: > >> Taka wrote: >> >>> The following study says so: >>> >>> http://hyper.ahajournals.org/cgi/content/abstract/51/2/376 >>> >> The full reference is >> >> Phillips SA, Jurva JW, Syed AQ, Syed AQ, Kulinski JP, Pleuss J, >> Hoffmann RG, Gutterman DD. >> Benefit of low-fat over low-carbohydrate diet on endothelial >> health in obesity. >> Hypertension. 2008 Feb;51(2):376-82. Epub 2008 Jan 14. >> PMID: 18195164 >> doi: 10.1161/HYPERTENSIONAHA.107.101824 >> <http://hyper.ahajournals.org/cgi/content/full/51/2/376> >> (full text is freely available) >> >>> and is advertised on the LEF site: >>> >>> Low fat beats low carb in heart disease prevention >>> >>> The February, 2008 issue of Hypertension published an article which >>> concluded that low fat diets were better than low carbohydrate diets >>> to prevent cardiovascular disease. >>> >>> Although both diets have their adherents in regard to their weight- >>> loss results, concern exists that the higher fat content of low >>> carbohydrate diets could increase cardiovascular disease risk. For the >>> current investigation, David D. Gutterman, MD of the Medical College >>> of Wisconsin in Milwaukee and his colleagues assigned 20 obese >>> participants to a low fat diet, providing 30 percent of its calories >>> in the form of fat, or a low carbohydrate diet for six weeks. Brachial >>> flow-mediated dilation, which evaluates endothelial function, was >>> measured at the beginning of the study, during the second week, and at >>> the study's conclusion. Blood pressure, weight, and cholesterol were >>> measured throughout the trial. >>> >>> Although all subjects experienced improvements in weight and blood >>> pressure, the percentage of arterial flow-mediated dilation declined >>> among those who followed the low carbohydrate diet, while >>> significantly improving in the low fat group. >> >> [snip] >>> >>> An addition risk incurred by low-carbohydrate diets is their reduced >>> levels of folic acid, a B vitamin that helps lower homocysteine. �The >>> composition of diet may be as important as the degree of weight loss >>> in determining the effect of dietary interventions on vascular >>> health,� Dr. Gutterman observed. >>> >> Low-carbohydrate diets don't need be low in folate. In fact the best >> sources of folate are organ meats such as liver and kidney, see >> >> <http://www.fineli.fi/topfoods.php?compid=2273&fuclass=all&specdiet=none&items=200&from=top&portion=100g&lang=en> >> >> <http://tinyurl.com/6qaadp> >> >> Ok, liver may not be recommendable for continuous use because of its >> high preformed vitamin A content and potentially high content of >> environmental toxins, and kidney may not please everyone's taste buds >> (although I found it delicious, when I still ate meat), but >> there are many other low-carbohydrate food items, which have high >> folate content, for example soy beans and various soy products such as >> soy flour and soy protein, egg yolks, asparagus, parsley, beetroot, >> green beans, kale, broccoli, Brussels sprouts, parsnip, and >> cauliflower. So if in this study the low-carbohydrate diet had low >> folate content, that sounds almost like intentional or alternatively >> shows ignorance, stupidity or/and bad planning. >> >> Many vegetables and berries are low-carbohydrate and contain plenty >> of antioxidants, which protect endothelium. Nuts are also >> low-carbohydrate and provide plenty of L-arginine, the only precursor >> for nitric oxide needed by endothelium for dilation. If this study did >> not include enough of these into the low-carbohydrate diet, that is bad >> planning (or intentional) and may have made results worse. >> > In the discussion chapter of the study it's mentioned that LC group got > more L-arginine than LF group, so perhaps that was not a problem, but > I still would like know why the folate content was low in LC group and > what and how much low-carbohydrate vegetables and berries LC group got. > There are also some low-carbohydrate fruit as the top of the following list shows: <http://www.fineli.fi/topfoods.php?compid=2034&fuclass=frufresh&specdiet=none&items=200&from=bottom&portion=100g&lang=en> <http://tinyurl.com/6buyvb> I wonder if nay of these were used in the LC group? -- Matti Narkia http://ma.gnolia.com/groups/Nutrition
From: Ron Peterson on 6 Aug 2008 12:05
On Aug 5, 1:32 am, Taka <taka0...(a)gmail.com> wrote: > Such confusing statements just distract people from the real problem > which of course is the excess of dietary Omega-6 and lure them to > buying different polyphenol rich supplements and Omega-3 fatty acids > to counteract the arachidonic acid metabolism. http://www.jacn.org/cgi/content/full/17/3/285 says: "The results of this study showed that the almond-based diet induced significant favorable changes in TC and LDL-C relative to the olive oil-based and control diets at a fat intake higher than that recommended by the National Cholesterol Education Program for cholesterol lowering, i.e., 39% calories vs. 30% calories [19]. In addition, there were no significant changes in body weight over the study period. The primary food sources of fat in each group, almonds, olive oil, and cheese/butter, were reflected in plasma lipid changes. The decreases in TC and LDL-C in the almond group were similar to the decreases previously achieved in 27 subjects who were placed on an almond-based diet [20]. In that investigation TC decreased from 235±4 to 216±4 mg/dl after 3 weeks and remained at approximately that level until the end of the 9-week study. Also in that study, as in the present almond-based diet, HDL-C levels were unchanged, with the reduction in TC being attributed to changes in LDL-C. However, the lack of a control group in our previous investigation precluded us from concluding whether the effect on lipids was due to the almonds or to other factors such as the influence of other substances contained in the diet. Both the olive oil and control groups in this study had lower total fat intakes (both 35% calories/fat) at 4 weeks than the almond group (39% calories/fat) suggesting that the effects were independent of total fat intake." -- Ron |