Tim G said...
From the For-What-It's-Worth Department, Glycemic Index has been shown in nutritional studies (not the junk science stuff) to be of less effect than previously thought. Not to worry. It will, like the incredible edible egg, be back. Give it a few years and more studies.
Do you have some specific studies in mind? But I can see where just going by the glycemic index alone might not get the job done. But I have not seen any studies where getting rid of bread,pasta, desserts etc and replacing with a low carb diet, higher fat, moderate protein diet did not have impressive results in several important ways, for however long folks keep eating that way.
There are a lot of studies out there that don't seem like junk science to me. For example, here is a randomized trial from the University of Pennsylvania School of Medicine, Philadelphia ; University of Colorado Health Sciences Center, Denver; Washington University School of Medicine, St. Louis ; and Thomas Jefferson University, Philadelphia, in the 2003 New England Journal of Medicine.
This one is extra interesting to me because it compares the plain vanilla Atkins diet - with no attempts to improve it by eating healthier
fats or reducing calories etc, just plain old high fat, probably high saturated fat, maybe high protein--- whatever and as much as the folks wanted to eat except carbs, AKA Atkins. Compared to the normally physician/dietician recommended a low fat, low calorie diet, which at least some folks might call(after greatly reducing both fat and calories) a starvation diet. Probably a slam dunk for low fat/low cal was expected.
Despite the great difference in these 2 diets, and despite the fact that one group was eating however much food they wanted, weight loss was double at 6 months and 1.6 times greater at 1 year for the low carb/high fat group.
But what about
systolic blood pressure? At 6 months, the high fat/low carb group was down 2.3% vs +1 for the low fat/low calorie group. At 1 year, low carb still minus 1% vs +1.7 for the usual recommended diet.
triglycerides? Atkins minus 17% at 1 year vs +1%! After a year of low fat and low carb, their TGLs actually went up, vs a very significant drop for the fat eaters who ate as much as they wanted!
In the LDL, finally low fat wins one, dropping 3% at 12 months vs a 0.3% increase for the high fat group.
Low fat also wins at total C, with a drop at 1 year of 2.9% vs a rise for Atkins of 0.1%. But here is where the tables turn: even though the total went up slightly, the good
was all of that and then some, with HDL going up a whopping 11% vs 1.6% for low fat. Which I'd say MORE than compensates for the 3% win at the LDL #s for low fat.
Summary: low fat/low cal wins total LDL by being 3.3% better. Low carb/high fat/ eat until full wins Triglycerides by 18%, HDL by 9.4%, blood pressure by 2.7% improved, and double the weight loss at 6 months and still 1.6 times more loss at 1 year, despite no calorie restriction.
Or, if you would rather have it in their own words regarding heart health risk factors and these two diets:
Somebody said... www.nejm.org/doi/full/10.1056/NEJMoa022207#t=article
An important health concern of consuming unrestricted amounts of saturated fat is the potential to increase the LDL cholesterol concentration, which is an established risk factor for coronary heart disease. In fact, at three months, the LDL cholesterol concentration tended to increase in the subjects on the low-carbohydrate diet but decreased in the subjects on the conventional diet, so the difference between groups was significant. Over the long term, however, the LDL cholesterol concentration among subjects on the low-carbohydrate diet was similar to base-line values, and the changes in LDL cholesterol concentrations did not differ significantly between the groups. These data suggest that the increased weight loss associated with the low-carbohydrate diet may offset the adverse effect of saturated fat intake on serum LDL cholesterol concentrations. Nonetheless, weight loss with the low-carbohydrate diet was not associated with the decreases in LDL cholesterol usually observed with moderate weight loss.4,30
In contrast, the low-carbohydrate diet was associated with greater decreases in serum triglycerides and greater increases in HDL cholesterol than was the conventional diet, and the levels of both are also important risk factors for coronary heart disease.31-33 The magnitude of these changes approximates that obtained with pharmacologic treatments, such as derivatives of fibric acid and niacin.31 Although part of this benefit may be due to the greater weight loss with the low-carbohydrate diet, the changes are greater than those expected from a moderate weight loss alone.30 Therefore, it is likely that the macronutrient composition of the diet contributed to the improvement in the HDL cholesterol–triglyceride axis. High-carbohydrate, low-fat diets decrease HDL cholesterol concentrations and increase serum triglyceride concentrations,34-37 whereas low-carbohydrate, high-fat diets decrease triglyceride concentrations16,27,37 and increase HDL cholesterol concentrations.15 Moreover, replacing dietary polyunsaturated or monounsaturated fat with carbohydrate is associated with an increased risk of coronary heart disease, as predicted by changes in triglyceride and HDL cholesterol concentrations.38
No doubt there are some conflicting studies, there always are. But considering several folks here have had similar results when they take a lower carb approach, and considering there are quite a few other studies that confirm this going back a lot of years, I personally don't feel it is junk science. But it definitely does not agree with every thing they(most authorities) have been telling us for 30+ years, aka conventional wisdom.www.ncbi.nlm.nih.gov/pubmed/15148063
Compared with a low-fat diet, a low-carbohydrate diet program had better participant retention and greater weight loss. During active weight loss, serum triglyceride levels decreased more and high-density lipoprotein cholesterol level increased more with the low-carbohydrate diet than with the low-fat diet.
Post Edited (BillyBob@388) : 4/15/2016 11:05:32 AM (GMT-6)