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Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
Beer-Sheva, Israel - Both a low-carbohydrate diet or a Mediterranean-style
diet may be "effective alternatives" to a low-fat diet, with more favorable effects on lipids and/or glycemic control, new research suggests [1]. The two-year study, which managed to keep almost 85% of the 322 study participants on one of the three diets for the entire period, offers the hope that weight-loss diets can be tailored to personal preferences, without sacrificing efficacy, researchers say. "Several recent one-year dietary studies have led the American Diabetes Association to state in January 2008 that low-carb diets should be considered for a maximum of one year," lead author on the study, Dr Iris Shai (Ben Gurion University of the Negev, Beer-Sheva, Israel), told heartwire. "The current two-year study suggests that one low-fat diet doesn't fit all, meaning that the old paradigm should be reconsidered." http://www.theheart.org/viewArticle...._id=tho16jul08 |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
Been doing the happy dance ever since I heard this on the evening news.
They emphasized the improvement in cholesterol. I'm so tired of people whining about what they can't eat because they have to watch their cholesterol and it's always fat. They'll have to excuse us long time low carbers for gloating a bit. Roger Zoul wrote: | Beer-Sheva, Israel - Both a low-carbohydrate diet or a | Mediterranean-style diet may be "effective alternatives" to a low-fat | diet, with more favorable effects on lipids and/or glycemic control, | new research suggests [1]. The two-year study, which managed to keep | almost 85% of the 322 study participants on one of the three diets | for the entire period, offers the hope that weight-loss diets can be | tailored to personal preferences, without sacrificing efficacy, | researchers say. "Several recent one-year dietary studies have led | the American Diabetes Association to state in January 2008 that | low-carb diets should be considered for a maximum of one year," lead | author on the study, Dr Iris Shai (Ben Gurion University of the | Negev, Beer-Sheva, Israel), told heartwire. "The current two-year | study suggests that one low-fat diet doesn't fit all, meaning that | the old paradigm should be reconsidered." | | http://www.theheart.org/viewArticle...._id=tho16jul08 |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
On Wed, 16 Jul 2008 18:56:23 -0400, Roger Zoul wrote
(in article ): Beer-Sheva, Israel - Both a low-carbohydrate diet or a Mediterranean-style diet may be "effective alternatives" to a low-fat diet, with more favorable effects on lipids and/or glycemic control, new research suggests [1]. The two-year study, which managed to keep almost 85% of the 322 study participants on one of the three diets for the entire period, offers the hope that weight-loss diets can be tailored to personal preferences, without sacrificing efficacy, researchers say. A loss of 3 - 4 kilograms over a two year period is a bit underwhelming no matter what the diet. -- Steve ** Posted from http://www.teranews.com ** |
Low-carb and Mediterranean diets beat low-fat for weight-loss,lipid changes at two years
Roger Zoul wrote:
Beer-Sheva, Israel - Both a low-carbohydrate diet or a Mediterranean-style diet may be "effective alternatives" to a low-fat diet, with more favorable effects on lipids and/or glycemic control, new research suggests [1]. The two-year study, which managed to keep almost 85% of the 322 study participants on one of the three diets for the entire period, offers the hope that weight-loss diets can be tailored to personal preferences, without sacrificing efficacy, researchers say. "Several recent one-year dietary studies have led the American Diabetes Association to state in January 2008 that low-carb diets should be considered for a maximum of one year," lead author on the study, Dr Iris Shai (Ben Gurion University of the Negev, Beer-Sheva, Israel), told heartwire. "The current two-year study suggests that one low-fat diet doesn't fit all, meaning that the old paradigm should be reconsidered." http://www.theheart.org/viewArticle...._id=tho16jul08 Shai I et al. Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet. The New England Journal of Medicine (NEJM), Volume 359:229-241, July 17, 2008, Number 3 http://content.nejm.org/cgi/content/full/359/3/229 elow the abstract of the study; "Background Trials comparing the effectiveness and safety of weight-loss diets are frequently limited by short follow-up times and high dropout rates. Methods In this 2-year trial, we randomly assigned 322 moderately obese subjects (mean age, 52 years; mean body-mass index [the weight in kilograms divided by the square of the height in ' meters], 31; male sex, 86%) to one of three diets: low-fat, restricted-calorie; Mediterranean, restricted-calorie; or low-carbohydrate, nonrestricted-calorie. Results The rate of adherence to a study diet was 95.4% at 1 year and 84.6% at 2 years. The Mediterranean-diet group consumed the largest amounts of dietary fiber and had the highest ratio of monounsaturated to saturated fat (P0.05 for all comparisons among treatment groups). The low-carbohydrate group consumed the smallest amount of carbohydrates and the largest amounts of fat, protein, and cholesterol and had the highest percentage of participants with detectable urinary ketones (P0.05 for all comparisons among treatment groups). The mean weight loss was 2.9 kg for the low-fat group, 4.4 kg for the Mediterranean-diet group, and 4.7 kg for the low-carbohydrate group (P0.001 for the interaction between diet group and time); among the 272 participants who completed the intervention, the mean weight losses were 3.3 kg, 4.6 kg, and 5.5 kg, respectively. The relative reduction in the ratio of total cholesterol to high-density lipoprotein cholesterol was 20% in the low-carbohydrate group and 12% in the low-fat group (P=0.01). Among the 36 subjects with diabetes, changes in fasting plasma glucose and insulin levels were more favorable among those assigned to the Mediterranean diet than among those assigned to the low-fat diet (P0.001 for the interaction among diabetes and Mediterranean diet and time with respect to fasting glucose levels). Conclusions Mediterranean and low-carbohydrate diets may be effective alternatives to low-fat diets. The more favorable effects on lipids (with the low-carbohydrate diet) and on glycemic control (with the Mediterranean diet) suggest that personal preferences and metabolic considerations might inform individualized tailoring of dietary interventions." The full text of the article seems also to be free, although to read it a free registrations is probably required. The best news report about this study is probably Medscape's Low-Carb and Mediterranean Diets Beat Low-Fat for Weight Loss, Lipid Changes at 2 Years http://www.medscape.com/viewarticle/577593?src=rss (requires free registration) Medscape's report is very clear, detailed and accurate. It presents some results in easily readable table format. Here is Medscape's presentation of the weight loss data: "Weight loss Group Low-fat (kg) Mediterranean (kg) Low-carb (kg) All patients 2.9 4.4 4.7 All completers 3.3 4.6 5.5 Men 3.4 4.0 4.9 Women 0.1 6.2 2.4" As can be seen the low-carb diet was best for men for weight loss, followed by the Mediterranean diet, but Mediterranean diet was the best for women, followed by the low-carb diet. Medscape's presentation of lipid changes is as follows: "Lipid changes Parameter Low-fat (mg/dL) Low-carb (mg/dL) Mediterranean (mg/dL) HDL +6.4 +8.4 +6.3 LDL 0.05 3.0 5.6 Triglycerides 2.8 23.7 21.8 Total 0.6 1.1 0.9 cholesterol/ HDL ratio" As can be seen, the important Total cholesterol/HDL ratio improved most in the low-carb diet and the Mediterranean diet was very close second. LDL was lowered most by Mediterranean diet followed by low-carb diet. Low-carb diet raised HDL most. Triglycerides were lowered most by low-carb and Mediterranean diets. Finally, below some selected comments from the end of the Medscape report: "- The mean BMI changes were 1.0, 1.5, and 1.5 kg/m2, respectively. - All groups had significant decreases in blood pressure and waist circumference, with no difference among the 3 groups. - Waist circumference was decreased by 2.8, 3.5, and 3.8 cm in the low-fat, Mediterranean, and low-carbohydrate groups, respectively. - Systolic blood pressure was reduced by 4.3, 5.5, and 3.9 mm Hg, respectively. - HDL cholesterol levels increased in all groups, with the greatest increase in the low-carbohydrate group (8.4 mg/dL). - Triglyceride levels decreased significantly, with the greatest decrease seen in the low-carbohydrate group (2.7 mg/dL). - The ratio of total to HDL cholesterol decreased in all 3 groups, greatest in the low-carbohydrate group (20%). - C-reactive protein decreased significantly in the Mediterranean and low-carbohydrate groups. - In the 36 participants with diabetes, only those in the Mediterranean group had a significant reduction in fasting plasma glucose levels (32.8 mg/dL). - Hemoglobin A1c rates decreased by 0.4%, 0.5%, and 0.9% in the low-fat, Mediterranean, and low-carbohydrate groups, respectively. - The Mediterranean and low-carbohydrate diets were feasible alternatives to the low-fat diet with some benefits, and personal preference could drive tailoring of diets for weight loss." Notice especially that the very important cardiovascular risk factor C-reactive protein (CRP) was reduced significantly only in the Mediterranean and low-carbohydrate groups. -- Matti Narkia http://ma.gnolia.com/groups/Nutrition |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
Yes, but the lipids findings are significant. That should get the
low-fatters who always says we are heading for heart attacks off our backs making us much lighter. Steve wrote: | | A loss of 3 - 4 kilograms over a two year period is a bit | underwhelming no matter what the diet. |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
FOB wrote in message ... Yes, but the lipids findings are significant. That should get the low-fatters who always says we are heading for heart attacks off our backs making us much lighter. Much lighter. :-) Cheri |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
Dr. Eades has made some intresting preliminary comments on this study.
http://www.proteinpower.com/drmike/weight-loss/low-carb-diet-trumps-low-fat-diet-yet-again/ Apparently there are a lot of questions, and the low-carb diet is certainly not standard LC, because LC participants were asked to raise carb intake to 120 g/day after the initial "induction" period. Meanwhile, the very-low-fat vegan starch-based diet proponent Dr. McDougall has come out strongly against the study's conclusions: http://www.drmcdougall.com/advertising_confuses_public.htm His primary complaints seem to be that (1) the "low-fat" diet was not really low-fat, with 30% of calories from fat (his plan runs around 7-10% fat), and (2) the Atkins Foundation funded the study. So nobody is happy with this one. I will go with my anectdotal, personal findings. On McDougall's program I lost quite a bit of weight. But I looked horrible, with really wrinkled skin, a very aged appearance. I had a lot of arthritic pain. And worst, I was hungry much of the time, no matter how much fat-free brown rice and beans I ate. I craved sugar. My hair became thin. My waistline underwent relative expansion, so I think my pre-existing insulin resistance worsened. LC allowed/allows me much easier weight loss, although slower, and my skin tone and body shape improved very noticeably. Like taking off 5-10 years! The waist/hip ration improved quickly. I actually found (and still find) myself eating more vegetables on LC than McDougall. And of course LC does away with the constant craving for food/sweets/starches. I can still remember, all these years later, how astonished I was, a couple weeks after starting LC, upon realizing I had completely forgotten to eat lunch! Never, never, never could have happened on vlf vegan like McDougall's plan. Hannah "Roger Zoul" wrote in message ... Beer-Sheva, Israel - Both a low-carbohydrate diet or a Mediterranean-style diet may be "effective alternatives" to a low-fat diet, with more favorable effects on lipids and/or glycemic control, new research suggests [1]. The two-year study, which managed to keep almost 85% of the 322 study participants on one of the three diets for the entire period, offers the hope that weight-loss diets can be tailored to personal preferences, without sacrificing efficacy, researchers say. "Several recent one-year dietary studies have led the American Diabetes Association to state in January 2008 that low-carb diets should be considered for a maximum of one year," lead author on the study, Dr Iris Shai (Ben Gurion University of the Negev, Beer-Sheva, Israel), told heartwire. "The current two-year study suggests that one low-fat diet doesn't fit all, meaning that the old paradigm should be reconsidered." http://www.theheart.org/viewArticle...._id=tho16jul08 |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
- In the 36 participants with diabetes, only those in the Mediterranean
group had a significant reduction in fasting plasma glucose levels (32.8 mg/dL). - Hemoglobin A1c rates decreased by 0.4%, 0.5%, and 0.9% in the low-fat, Mediterranean, and low-carbohydrate groups, respectively. Funny, these two statements seem to contradict each other... Take care, Hamburger |
Low-carb and Mediterranean diets beat low-fat for weight-loss,lipid changes at two years
"Hannah Gruen" wrote:
Dr. Eades has made some intresting preliminary comments on this study. http://www.proteinpower.com/drmike/weight-loss/low-carb-diet-trumps-l... Thanks for the pointers to Eades and McDougall. Apparently there are a lot of questions, and the low-carb diet is certainly not standard LC, because LC participants were asked to raise carb intake to 120 g/day after the initial "induction" period. The level of 120 grams per day is above my maintenance limit. If I eat that much carb my appetite starts going up and my weight starts drfting up. It makes me wonder why they'd put folks on 2 months at 20, then put them at a level that will be over their maintenance limit for some. It doesn't make sense. Why not have them actually try, you know, either the real Atkins plan or the real Eades plan? Meanwhile, the very-low-fat vegan starch-based diet proponent Dr. McDougall has come out strongly against the study's conclusions: http://www.drmcdougall.com/advertising_confuses_public.htm His primary complaints seem to be that (1) the "low-fat" diet was not really low-fat, with 30% of calories from fat (his plan runs around 7-10% fat), and If they aren't doing a real low carb plan why should anyone expect they do a real low fat plan. Sigh. (2) the Atkins Foundation funded the study. This is both valid and invalid at the same time. It's valid because the Atkins Foundation can't be expected to fund a project that looks in advance like low carb is going to lose - Which makes it even more bizzare that they picked a level hign enough to exceed the mainteance limit of some. It's invalid because studies get duplicated when they are in doubt. So nobody is happy with this one. I will go with my anectdotal, personal findings. On McDougall's program I lost quite a bit of weight. But I looked horrible, with really wrinkled skin, a very aged appearance. I had a lot of arthritic pain. And worst, I was hungry much of the time, no matter how much fat-free brown rice and beans I ate. I craved sugar. My hair became thin. My waistline underwent relative expansion, so I think my pre-existing insulin resistance worsened. I tried low fat for 20 years, gained 50 pounds, was constantly hungry. I am well aware that low fat works for some percentage of the population, I'm just not in that percentage. LC allowed/allows me much easier weight loss, I think this is the single largest advantage low carb has - For so many people it turns off the cravings, turns down the appetite. It no longer triggers hunger to gradually reduce portion sizes. although slower, and my skin tone and body shape improved very noticeably. Like taking off 5-10 years! The gray in my hair saw about 5 years worth of set back in its advance. The waist/hip ration improved quickly. I wish I'd seen that bit. I actually found (and still find) myself eating more vegetables on LC than McDougall. Yeah. Eating veggies is the low carb way. Strange how that worked out. Strange enough that people who have never tried low carb don't think it's a feature of the system. |
Low-carb and Mediterranean diets beat low-fat for weight-loss,lipid changes at two years
Hamburger wrote:
- In the 36 participants with diabetes, only those in the Mediterranean group had a significant reduction in fasting plasma glucose levels (32.8 mg/dL). - Hemoglobin A1c rates decreased by 0.4%, 0.5%, and 0.9% in the low-fat, Mediterranean, and low-carbohydrate groups, respectively. Funny, these two statements seem to contradict each other... Good observation. I noticed the same thing and quietly wondered about it, too. From the Figure 4. Changes in Biomarkers According to Diet Group and Presence or Absence of Type 2 Diabetes. http://content.nejm.org/cgi/content/full/359/3/229/F4 you can see, that fasting plasma glucose reductions of diabetic people in the Mediterranean diet and low-carb diet groups were very close to each other at 12 months, -23.6 and -18.1, respectively, but after that Mediterranean diet group continued downward trend, but the trend of the low-carb group turned upwards, so that at 24 months the Mediterranean group was at -32.8, but the low-carb group had 1.2 _increase_. I wonder what happened after 12 months to cause this swing upwards in the low-carb group? The reduction of HOMA-IR (homeostasis model assessment of insulin resistance) was also largest in the Mediterranean group followed by the low-carb group and smallest in the low-fat group. But why the reduction of HbA1c behaved differently from fasting plasma glucose and HOMA-IR, so that it was larger in low-carb group than in the Mediterranean group, is a mystery to me, too. I wish that the authors had handled this in the Discussion chapter or elsewhere in the text, but apparently they didn't. Perhaps people familiar with diabetes could have some kind of explanation or speculation about this? -- Matti Narkia http://ma.gnolia.com/groups/Nutrition |
Low-carb and Mediterranean diets beat low-fat for weight-loss,lipid changes at two years
HbA1c
LoFat 0.4% Med 0.5% LoCarb 0.9% fBG (1 yr, 2 yr mg/dL) LoFat Med -23.6, -32.8 LoCarb -18.1, 1.2 *But why the reduction of HbA1c behaved differently from fasting plasma glucose and HOMA-IR, so that it was larger in low-carb group than in the Med group, is a mystery to me, too. *Perhaps people familiar with diabetes could have some kind of explanation or speculation about this? Is it possible that a low-carb diet shifts cellular machinery towards efficient fat metab, decreasing carb metab efficiency, thus increasing insulin resistance. I'm not sure if HOMA takes this into account. Ideally, insulin resistance should be tested after all three groups are returned to a reference diet at the end of trials. An improved cholestrol profile and Hb1Ac may not relate to improved fBG and IR due to additional factors. For example, loCarb will likely give lower HbA1c. But loCarb is higher in lipophilic toxins (ie PCBs, dixions, etc). TCDD, a potent dioxin, increases mito ROS. Cellular ROS is likely to increase insulin resistance. Lipophilic toxins are highest in animal, fish, dairy & egg fats. [TCDD decreases ATP levels and increases reactive oxygen production through changes in mitochondrial F(0)F(1)-ATP synthase and ubiquinone.] Mitochondria generate ATP and participate in signal transduction and cellular pathology and/or cell death. TCDD (2,3,7,8-tetrachlorodibenzo- p-dioxin) decreases hepatic ATP levels and generates mitochondrial oxidative DNA damage, which is exacerbated by increasing mitochondrial glutathione redox state and by inner membrane hyperpolarization. This study identifies mitochondrial targets of TCDD that initiate and sustain reactive oxygen production and decreased ATP levels. One week after treating mice with TCDD, liver ubiquinone (Q) levels were significantly decreased, while rates of succinoxidase and Q-cytochrome c oxidoreductase activities were increased. However, the expected increase in Q reduction state following TCDD treatment did not occur; instead, Q was more oxidized. These results could be explained by an ATP synthase defect, a premise supported by the unusual finding that TCDD lowers ATP/O ratios without concomitant changes in respiratory control ratios. Such results suggest either a futile cycle in ATP synthesis, or hydrolysis of newly synthesized ATP prior to release. The TCDD-mediated decrease in Q, concomitant with an increase in respiration, increases complex 3 redox cycling. This acts in concert with glutathione to increase membrane potential and reactive oxygen production. The proposed defect in ATP synthase explains both the greater respiratory rates and the lower tissue ATP levels. PMID: 17109908 |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
"Doug Freyburger" wrote (2) the Atkins Foundation
funded the study. This is both valid and invalid at the same time. True. However, it is interesting to note that Doc McDougall bitched for years that Dr. Atkins made a lot of money off his diet plan, but never did any research. Now that the Atkins organization funds a study, he won't accept the results! The gray in my hair saw about 5 years worth of set back in its advance. Wow! Now that is one I never saw. How nice! Yeah. Eating veggies is the low carb way. Strange how that worked out. Strange enough that people who have never tried low carb don't think it's a feature of the system. Yeah. I loved veggies as a kid, but I don't find them very appealing as part of a fat-free, high-starch meal. I like my olive oil sautees with a sliced clove or 2 of garlic thrown in before the veggies. In fact that is what I had for dinner. A huge panful of broccoli sauteed in olive oil and garlic, then pepper jack cheese and eggs stirred in and cooked. Salt and red pepper flakes to taste. Yum. My whole family loves broccoli. My grandson expects it whenever he is here for dinner. My new puppy... the first food he ever tried to steal and eat from a grocery bag carelessly left on the floor... yep, broccoli. I give him little sprigs of the raw stuff whenever I have it. He inhales it. Hannah |
Low-carb and Mediterranean diets beat low-fat for weight-loss,lipid changes at two years
jay wrote:
HbA1c LoFat 0.4% Med 0.5% LoCarb 0.9% fBG (1 yr, 2 yr mg/dL) LoFat Med -23.6, -32.8 LoCarb -18.1, 1.2 But why the reduction of HbA1c behaved differently from fasting plasma glucose and HOMA-IR, so that it was larger in low-carb group than in the Med group, is a mystery to me, too. Perhaps people familiar with diabetes could have some kind of explanation or speculation about this? . . . . I read in one report that the low carb group started out at 20 grams of carb (with a focus on vegetable sources of protein and fat) and increased their intake over the two years to around 110 grams. It sounds like, toward the end of the study, that the low-carb and Med diets might have been fairly similar. I can't figure out what these people would be eating if they were minimizing/abstaining from meat, cheese, eggs, etc. Israel is in the Middle East. Surely, a Mediterranean style diet is closest to what they would normally eat and most would probably aim as close to what they would be traditionally eating as the confines of their diet group allowed. At 110 grams, they could work in beans, pasta, many wheat-based dishes, etc. I think that trying to solve the "mystery" of the results is probably hopeless. Kind of a "What Did They Eat? And When Did They Eat It?" conundrum. |
Low-carb and Mediterranean diets beat low-fat for weight-loss,lipid changes at two years
"Hannah Gruen" wrote:
"Doug Freyburger" wrote: The gray in my hair saw about 5 years worth of set back in its advance. Wow! Now that is one I never saw. How nice! It's a fairly common complaint that 6 months into a very successful loss phase hair falls out. It's not as common to come back later to report it ended up coming back in thicker or less gray or whatever. Yet that's what usually happens. But it's easier to come asking about a problem than to come back several months later to report on the long term result. |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
"Cookie Cutter" wrote I read in one report that the low carb group started out at 20 grams of carb (with a focus on vegetable sources of protein and fat) and increased their intake over the two years to around 110 grams. It sounds like, toward the end of the study, that the low-carb and Med diets might have been fairly similar. I can't figure out what these people would be eating if they were minimizing/abstaining from meat, cheese, eggs, etc. Israel is in the Middle East. Surely, a Mediterranean style diet is closest to what they would normally eat and most would probably aim as close to what they would be traditionally eating as the confines of their diet group allowed. At 110 grams, they could work in beans, pasta, many wheat-based dishes, etc. I think that trying to solve the "mystery" of the results is probably hopeless. Kind of a "What Did They Eat? And When Did They Eat It?" conundrum. Yes, I've been reading more about this one, too. Even more puzzling (to me) is the fact that the calories were restricted for the low-fat and Mediterranean diet groups, but not for the LC group. My guess would be that as the LC group started adding back carbs, they lost the natural appetite suppresant function of the diet and calories may have increased? Not sure, as I haven't read the full study or perused the data. If total calories in is substantially different for the different groups, that can make a difference in findings that may trump effects of macronutrient diet makeup. At any rate, it seems like it would have been a good idea to keep as many parameters as possible equivalent, if they wanted to compare diets. Like calories, for instance. Sometimes I read these research designs, and wonder who on earth reviewed and approved them. They just defy logic. Anyway, it's just not a well-designed study, IMO, even if it does show advantage for the lower-carb plans (no surprise there.) HG |
Low-carb and Mediterranean diets beat low-fat for weight-loss,lipid changes at two years
Hannah Gruen wrote:
"Cookie Cutter" wrote I read in one report that the low carb group started out at 20 grams of carb (with a focus on vegetable sources of protein and fat) and increased their intake over the two years to around 110 grams. It sounds like, toward the end of the study, that the low-carb and Med diets might have been fairly similar. I can't figure out what these people would be eating if they were minimizing/abstaining from meat, cheese, eggs, etc. Israel is in the Middle East. Surely, a Mediterranean style diet is closest to what they would normally eat and most would probably aim as close to what they would be traditionally eating as the confines of their diet group allowed. At 110 grams, they could work in beans, pasta, many wheat-based dishes, etc. I think that trying to solve the "mystery" of the results is probably hopeless. Kind of a "What Did They Eat? And When Did They Eat It?" conundrum. Yes, I've been reading more about this one, too. Even more puzzling (to me) is the fact that the calories were restricted for the low-fat and Mediterranean diet groups, but not for the LC group. I think that the idea was that higher protein adn fat consumption and lower carb consumption of LC diet suppresses appetite so that LC group kind of automatically and voluntarily reduces its calories. It seems to have also worked that way. My guess would be that as the LC group started adding back carbs, they lost the natural appetite suppresant function of the diet and calories may have increased? Not sure, as I haven't read the full study or perused the data. If total calories in is substantially different for the different groups, that can make a difference in findings that may trump effects of macronutrient diet makeup. If you look at Table 2. Changes in Dietary Intake, Energy Expenditure, and Urinary Ketones during 2 Years of Intervention http://content.nejm.org/cgi/content/full/359/3/229/T2 you'll see that calorie reductions in LC and LF groups were almost identical. In the Mediterranean group the reductions were a little smaller, but still not statistically significantly different from LC and LF groups. At any rate, it seems like it would have been a good idea to keep as many parameters as possible equivalent, if they wanted to compare diets. Like calories, for instance. As I mentioned, the realized calorie reductions were not statistically significantly different between groups, and in LC and LF groups they were almost identical. Sometimes I read these research designs, and wonder who on earth reviewed and approved them. They just defy logic. Anyway, it's just not a well-designed study, IMO, even if it does show advantage for the lower-carb plans (no surprise there.) I have to disagree with you. Although not completely without flaws, this is, however, a large, long term (2 years), well-designed and well-published (NEJM) study, which compared well-designed and well-known diets. Additionally, if it wasn't well-designed, it probably wouldn't have been published in NEJM, the number one medical journal in the world. Here's an interesting excerpt from Low-fat Diets May Not Be Best For Weight Loss, Study Suggests http://www.sciencedaily.com/releases/2008/07/080716171134.htm : "Dr. Iris Shai is a researcher at the S. Daniel Abraham International Center for Health and Nutrition in the Department of Epidemiology at Ben-Gurion University of the Negev. She conceived the study with Dr. Stampfer, the senior author, while she was a Fulbright fellow at Harvard School of Public Health and Channing Laboratory in Boston, Massachusetts." Dr. Meir Stampfer is one of the authors of the study in question and a very remarkable scientist. Harvard's press release HSPH Department Chairs Meir Stampfer and Walter Willett Most Cited Scientists of the Decade in Clinical Medicine Harvard School of Public Health Press Release, Friday, September 23, 2005 http://www.hsph.harvard.edu/press/releases/press09232005.html from September 23, 2005, writes about him as follows: "Meir Stampfer, Chair of the Department of Epidemiology at the Harvard School of Public Health (HSPH) has been ranked the number one most cited scientist in clinical medicine for the last decade. According to ISI Essential Science Indicators, 376 of his published research findings were cited nearly 31,000 times between 1995 and August of 2005." Dr. Stampfer's web page at Harvard: Meir Stampfer Professor of Nutrition and Epidemiology Department of Epidemiology Department of Nutrition http://www.hsph.harvard.edu/faculty/meir-stampfer/ I wonder, if a major force like Stampfer would have allowed his name to be used in this study, if there were any doubts about its quality. -- Matti Narkia http://ma.gnolia.com/groups/Nutrition |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
On 2008-07-21, Matti Narkia wrote:
Hannah Gruen wrote: Anyway, it's just not a well-designed study, IMO, even if it does show advantage for the lower-carb plans (no surprise there.) I have to disagree with you. Although not completely without flaws, this is, however, a large, long term (2 years), well-designed and well-published (NEJM) study, which compared well-designed and well-known diets. Additionally, if it wasn't well-designed, it probably wouldn't have been published in NEJM, the number one medical journal in the world. Here's an interesting excerpt from Low-fat Diets May Not Be Best For Weight Loss, Study Suggests http://www.sciencedaily.com/releases/2008/07/080716171134.htm : "Dr. Iris Shai is a researcher at the S. Daniel Abraham International Center for Health and Nutrition in the Department of Epidemiology at Ben-Gurion University of the Negev. She conceived the study with Dr. Stampfer, the senior author, while she was a Fulbright fellow at Harvard School of Public Health and Channing Laboratory in Boston, Massachusetts." The reason this study was conducted and published is simply because it's the type of thing which can attract media attention these days. The institutions behind it become visible in the act of doing something regarding a large problem which faces the general public. It's nothing more than a circus show, of absolutely no consequence. It's poor science, but it doesn't appear dishonest. That is to say, as long as no data was falsified, no reputations are going to be damaged by this type of thing. Dr. Meir Stampfer is one of the authors of the study in question and a very remarkable scientist. Harvard's press release Maybe Stampfer is so confident in his credentials, that he no longer gives a damn. If he wants to do a little bit of fun, unscientific pig farming, he can boldly attach his name to it without scathing his reputation. HSPH Department Chairs Meir Stampfer and Walter Willett Most Cited Scientists of the Decade in Clinical Medicine Harvard School of Public Health Press Release, Friday, September 23, 2005 http://www.hsph.harvard.edu/press/releases/press09232005.html from September 23, 2005, writes about him as follows: "Meir Stampfer, Chair of the Department of Epidemiology at the Harvard School of Public Health (HSPH) has been ranked the number one most cited scientist in clinical medicine for the last decade. According to ISI Essential Science Indicators, 376 of his published research findings were cited nearly 31,000 times between 1995 and August of 2005." In science, people cut-and-paste citations from other papers, without even /reading/ the original papers that are being cited! Do you know that misspellings in citations propagate among unrelated papers from different authors? The more citations you have in your paper, the more it seems that you have done a thorough job of covering the prior research. There is a pressure to cite, which leads to padded citations lists. A citation is not always positive. There are citations which are used to exemplify lesser quality prior work. If you include such a citation, it gives you an opportunity to extend your paper by a paragraphs of text which does nothing but criticize the earlier work, and explain how the new work improves on it. The choice of citation can also be influenced by the degree to which the cited researcher confirms a hypothesis which the new researcher is trying to argue. If your paper argues that unlimited amounts of energy can be obtained from a perpetually moving machine, a significant fraction of your citations will be to other crackpot papers. |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
"Doug Freyburger" wrote in message ... "Hannah Gruen" wrote: "Doug Freyburger" wrote: The gray in my hair saw about 5 years worth of set back in its advance. Wow! Now that is one I never saw. How nice! It's a fairly common complaint that 6 months into a very successful loss phase hair falls out. It's not as common to come back later to report it ended up coming back in thicker or less gray or whatever. Yet that's what usually happens. But it's easier to come asking about a problem than to come back several months later to report on the long term result. Yes, true. Well, and younger people without much or any gray in their hair won't have any change of course. But this is the first time I recall hearing anyone note lessening of the gray from LC. Cool. BTW, I recall reading way in the past that increasing certain B vitamins can sometimes reverse premature graying. I know you're like me - much healthier, high-nutrient-density fare since starting LC. I can say I virtually never get sick any more. I'm not sure to attribute that to LC (I think that is part of it) or to the fact that I started supplementing with higher doese of Vitamin D. Probably both. HG |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
"Matti Narkia" wrote
I think that the idea was that higher protein adn fat consumption and lower carb consumption of LC diet suppresses appetite so that LC group kind of automatically and voluntarily reduces its calories. It seems to have also worked that way. Matti I am going to defer to you on this one, more or less. From reading your posts over the years, it's clear you know a lot more about this stuff than do I. However, from a non-biological scientist POV, it makes absolutely no logical sense to me to set up a study in which calories are controlled in only 2 of 3 groups. Yes, as it turned out the group that was not controlled for calories ended up eating the same amount as the other groups. But what if it hadn't? Why take that chance? I don't get it. Table 2. Changes in Dietary Intake, Energy Expenditure, and Urinary Ketones during 2 Years of Intervention http://content.nejm.org/cgi/content/full/359/3/229/T2 you'll see that calorie reductions in LC and LF groups were almost identical. In the Mediterranean group the reductions were a little smaller, but still not statistically significantly different from LC and LF groups. Again, since I assume that appetite reduction was not one of the parameters being studied here, why not just control all groups? I have to disagree with you. Although not completely without flaws, this is, however, a large, long term (2 years), well-designed and well-published (NEJM) study, which compared well-designed and well-known diets. Additionally, if it wasn't well-designed, it probably wouldn't have been published in NEJM, the number one medical journal in the world. Well, if you say so. I have, however, noted quite a bit of carping on various blogs of people who really are (unlike me) experts at this stuff. I'm not going to argue that the results are not interesting or valid, however. Here's an interesting excerpt from Low-fat Diets May Not Be Best For Weight Loss, Study Suggests http://www.sciencedaily.com/releases/2008/07/080716171134.htm : I think appeals from authority are a bit weak. And yet, I did just that (above). I know some of the criticism has revolved around the fact that none of the 3 diets tested were done in a way that satisfied all proponents of such diets. LC had too many carbs. LF wasn't low enough. Etc. Overall it seems to have been a reasonable effort, but had caloric intake differed substantially from group to group, that would have been a different story, wouldn't it have? Why take that chance? HG |
Low-carb and Mediterranean diets beat low-fat for weight-loss,lipid changes at two years
"Hannah Gruen" wrote:
... I know some of the criticism has revolved around the fact that none of the 3 diets tested were done in a way that satisfied all proponents of such diets. Thinking about this since it came out I've ended up at a different vewpoint than my initial reaction. The low carb group ended up at 120 grams per day after a couple of months at 20. That's not a weight loss diet at all. In fact for me it isn't even a maintenance level. But there are plenty of people who do have 120 as a maintenance level. LC had too many carbs. LF wasn't low enough. Etc. Since the LC group was a maintenance group, I don't think the intent was to compare loss phases at all. I think the intent was to compare the impact of the maintenace phases on long term health. Since the experiement lasted 2 years it was too long for just doing loss phases for any of the plans. Given the experiment is about the maintenance phase (inferred but not mentioned in the abstract) the fact that there was an average loss on all of the plan types is nice but irrelevant. I'd want to know what percentage regained not what the mean value is. Since it's not about loss all the mean value means is the ones with net loss out numbered the ones with net gain, and it was number of pounds in each direction that got out numbered not number of subjects. Being a comparison of the maintenance phases, the health markers other than average loss are all more important results. Overall it seems to have been a reasonable effort, but had caloric intake differed substantially from group to group, that would have been a different story, wouldn't it have? There is precedent from prior studies that LC groups do not get instruction to reduce total calories by LF groups do. Neither of us agrees with that precedent but that precedent seems to be the source for it. Why take that chance? I wonder about encouraging low carbers to cut total calories. I think about posters to ASDLC over the years - Some have wanted to use the appetite suppression of ketosis to drive their calorie intake levels down to starvation levels with minimum or no discomfort. I would certainly hesitate to push a group of low carbers to reduce calories if I were in charge of an experiment in fear of harming someone with an eating disorder I hadn't detected. |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
I know this is heresy but I think the best thing to come out of this study
is the positive publicity it is generating for low carb. I'm so tired of people trashing eggs, meat with any fat and butter saying they have to watch their cholesterol. And if the LCers were indeed at maintenance levels, it shows that you don't have to be doing induction, which most people seem to think is what LC is, to obtain many of the benefits. We shouldn't be surprised that a study whose results we like has its flaws, that has certainly been true of the studies that had results we didn't like. There are so many variables and such difficulty in controlling the behavior of the subjects, that no dietary study done on humans will be perfect. |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
That sure isn't what I heard on the TV reports. Nor did I read it in the
things posted here? It said that LC was the best in improving lipids. No one mentioned types of fats or 40% carbs, perhaps that's the Mediterranean diet. Susan wrote: | | How do you figure it's positive to say that a diet that's low fat and | 40% carbohydrate is the best? Or that it's necessary to replace | animal protein with vegetable proteins to get the results? | | Susan |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
Where did you see such articles, I haven't seen any? You do have to realize
that the people who have been creating low fat "Heart Smart" recipes for years are going to have to take baby steps in changing their advice. Even if the best study in the world came out they would refuse to do a complete about face. I guess I see any progress toward them accepting LC as a good thing. Susan wrote: | | Not if they're reading the rampant articles in which low carb is being | touted as low on meat and emphasizes vegetable proteins. They're | getting the message that low carb is only safe that way. | | Susan |
Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years
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