Am I on the wrong track?
Is the fat contributing to his breaking out?
it’s basically around his mouth, chin area.

Do you have a better answer for him, than I have?
Is it the fat, or just hormones?
HELP!

thanks,
Eve

Hi Eve–

MRE

As a flagrant example of not taking co-variables into account I remember a bit of research done by an Amsterdam GP at the beginning of last century. He had come to the conclusion that being under the sway of socialist ideas was probably a matter of having been poisoned by white bread. He had noticed that in the Amsterdam neighborhoods where there were most votes for the socialist party there was also the highest consumption of white bread.

Interesting. I wonder where the votes for Obama will come from?

MRE

Are my comments still awaiting moderation?

I’m working through them.

We all can.

MRE

This study purported to trace the correlation between protein intake and mortality in the population of the Women’s Lifestyle and Health cohort study, 42,237 women in all, over the intial period 1991-1992 with a twelve year follow up through linkages to national registries. The original material was provided by an extensive questionnaire.

The results seemed to show that a decreasing carbohydrate and an increasing protein intake were associated with higher mortality, and particularly cardiovascular mortality, among women.

The weak spot of this study as acknowledged in the text is of course that there is no guarantee that the lifestyle respondents indicated at the beginning of the study was maintained over the next twelve years. Also, I wonder whether the concomitant variables of a lifestyle marked by a high consumption of meat were really kept constant.

Also as long as there is no non-controversial medical explanation provided for the alleged link between protein intake and higher cardiovascular mortality there remains an argument open that this statistical link could possibly be spurious. In the studies cited above we have seen that in all cases a low-carb diet led to an improvement in lipid profiles – so why the cardiovascular mortality?

One of the the contributors of the Lagiou et al. study, A.Trichopoulou, also led a study which I didn’t find in the European Journal of Medicine (Crowe’s indication) but in the European Journal of Clinical Nutrition. The complete reference is :
Trichopoulou A. et al (2007), Low-carbohydrate-high-protein diet and long-term survival in a general population cohort, European Journal of Clinical Nutrition, 61, pp.575-581.

The abstract says: “ Follow-up was performed from 1993 to 2003 in the context of the Greek component of the European Prospective Investigation into Cancer and nutrition. Participants were 22 944 healthy adults, whose diet was assessed through a validated questionnaire. Participants were distributed by increasing deciles according to protein intake or carbohydrate intake, as well as by an additive score generated by increasing decile intake of protein and decreasing decile intake of carbohydrates. Proportional hazards regression was used to assess the relation between high protein, high carbohydrate and the low carbohydrate–high protein score on the one hand and mortality on the other.”

The results seemed to suggest that higher intake of carbohydrates was linked to a significant decrease in mortality whereas higher protein intake was correlated to a nonsignificant increase in mortality. The combination of low carbohydrate-high protein seemed to be particularly fatal with regard to both cardiovascular and cancer mortality. So the conclusion was that ‘prolonged consumption of diets low in carbohydrates and high in protein is associated with an increase in total mortality’.

The same strictures relevant to the Swedish study apply here.

The results of both the Swedish and Greek study are, as far as cardiovascular disease is concerned, flagrantly contradicted by a study published in the New England Journal of Medicine which I believe to be superior to these other studies, because of the size and the nature of its population (nurses), because of the regular updating through questionnaire of food data and because of the period involved (twenty years).

The reference is:
Halton Th. et al. (2006), Low-carbohydrate score and the risk of coronary heart disease, New England Journal of Medicine, 355(19).

It concerns here an analysis in the context of the Nurses Health Study, with a total of more than 82,000 respondents who every two years filled out a questionnaire about their food intake and were followed for a period of twenty years. The resullts suggested that there was no correlation between low carbohydrate intake and cardiovascular disease and that in fact, if vegetable sources of protein and fat were consumed, there was a negative correlation. There was, by contrast, a mild link between total carbohydrate intake and coronary heart disease and a strong link if this food contained a high glycemic load.

One critic of this study held that there were not enough respondents in this study who consumed less than 30 % carbohydrates to come to positive conclusions.

Overall I would say however that Dr.Crowe’s case on this point has not really been confirmed.

I did a pretty thorough analysis of the Swedish study that I never got around to writing up and posting. Basically the results of that study are worthless as far as having any predictability to the longevity effects of low-carb diets for a couple of reasons. First, it’s an epidemiological study, which, as I’ve posted on countless times, can’t show causality. Second, the relation between carbs and protein and longevity are within a range of protein and (especially) carbs that are not found in low-carb diets and, therefore, can’t be extrapolated to them.

MRE

Uh, you don’t need any carbs at all for energy. You can get it from fat, and without the negative metabolic consequences that come along with the carbs. Spend some time with a medical biochemistry textbook.

MRE

The McAuley reference could neither be tracked down in Proquest nor in Ovid Medline . At the pagenumbers indicated (pp.1-8) there appeared in fact a different article that year. There was however a McAuley article in the following year for which the correct reference is:
McAuley K.A. et al. (2006), Long-term effects of popular diet approaches on weight loss and features of insulin resistance, International Journal of Obesity, Vol.30 Iss.2 p.342.

This article reports on a comparison between a high-protein, a high-fat and high-carbohydrate diet administered over a year to a total of 93 insulin-resistant overweight women.
The abstract says: “During the second 6 months the HF group had increases in waist circumference …, triglycerides … and 2 h glucose … . Overall there was substantial sustained improvement in waist circumference, triglycerides and insulin in the HP group and sustained but more modest changes on HC. Dietary compliance at 12 months was poor in all groups.”
So at 12 months the high protein diet was superior to both the high fat and high carbohydrate diet as far as waist circumference was concerned. It was also superior as regards triglycerides and insulin. Thus if the low-carbohydrate diet (the object of Dr.Crowe’s strictures) is defined as a high protein diet these strictures miss the mark. If, however, it is defined as a high fat diet he has a case here. Altogether a rather ambiguous result as far as his thesis is concerned.

I could not track down the Nordmann article either whatever I tried until I found out that it didn’t appear in the Annals of Internal Medicine, as indicated by Crowe, but in the Archives of Internal Medicine. The rest of the reference is the same.

This article deserves to be taken a bit more seriously because it utilises a Cochrane Search Strategy to report on five trials involving a comparison of low-carbohydrate diets versus low-fat diets. As far as weight loss is concerned the abstract states: “After 6 months, individuals assigned to low-carbohydrate diets had lost more weight than individuals randomized to low-fat diets …. This difference was no longer obvious after 12 months …”
And regarding blood pressure and lipid profile it stated: “ There were no differences in blood pressure. Triglyceride and high-density lipoprotein cholesterol values changed more favorably in individuals assigned to low-carbohydrate diets … but total cholesterol and low-density lipoprotein cholesterol values changed more favorably in individuals assigned to low-fat diets …”

Thus here it appears that a low-carbohydrate diet doesn’t offer any weight loss advantages over one year compared to a low fat diet but once again it seems that there are no risks engendered for CHD as far as the lipid profile is concerned – rather the opposite.

It took me also some time to track down the Stern article because here too the reference was faulty. In this case as far as the page numbers were concerned ( I hope for Dr.Crowe that none of his students get to see this post otherwise they would have a case to cite against him next time he marks them down for poor referencing). The appropriate reference is:
Stern L. et al. (2004), The effects of Low-Carbohydrate versus Conventional Weight Loss Diets in Severely Obese Adults: One Year Follow-Up of a Randomized Trial, Annals of Internal Medicine, Vol.140 Iss.10, pg.778, 8pgs.

This is what the abstract said:
“Stern et al review the 1-year outcomes between a low-carbohydrate diet versus a low-fat weight loss diet in severely obese adults with a high prevalence of diabetes or metabolic syndrome. They found out that participants on a low-carbohydrate diet had better results overall than those on a low-fat, restricted-calorie diet. Furthermore, weight loss was the same in the 2 groups, but patients on the low-carbohydrate diet had less atherogenic dyslipidemia and better glycemic control.”
So here too the low-carbohydrate diet seemed to have no advantage as far as weight loss was concerned but was distinctly superior in its health outcome.

The Truby article dealt with a comparison over a six month period between four diets:available in the UK: Atkins, Slim-Fast Plan, Weight Watchers pure points program and Rosemary Conley’s Eat Yourself Slim diet. The average weight loss was 5.9 kg. The abstract says further: “The Atkins diet resulted in significantly higher weight loss during the first four weeks, but by the end was no more or less effective than the other diets.” So here too Crowe seems to be scoring a point about a low-carb diet not offering any weight advantages as is also the case with the following Dansinger article (which I found equally hard to track down because of poor referencing – Crowe spelt the name Dasinger).

This Dansinger article also reports on a comparison, in this case that between Atkins, Zone, Weight Watchers and Ornish. The test was conducted for over a year on 160 overweight or obese adults with known hypertension, dyslipidemia or fasting hyperglycemia, varying in age between 22 to 72 years. Weight loss varied between 4.8 kg (Atkins) and 7.3 kg (Ornish) but the authors take care to say that the amount of “weight loss was associated with self-reported dietary adherence level … but not with diet type …”

So this also seems to confirm Crowe’s point about low-carb diets not offering any weight loss advantage, but once again clearly not as far as his warning about CHD risk factors is concerned because the authors distinctly state in their conclusion that “each popular diet modestly reduced body weight and several cardiac risk factors at 1 year.”

So what is the score as far as Crowe’s double thesis on the low-carb diet not offering any weight advantages over one year and the risk factors for CHD are concerned.
Concerning the first factor five of the eight references cited seem to support his view and one is ambiguous. Concerning the alleged risk factors for CHD he appears to be totally wrong. In so far as these risk factors have to do with lipid profile the low-carb diet had in all cases a favorable outcome.

Crowe has also given two references concerning long term health hazards. I will discuss these in my next post.

Hey Arie–

MRE

The Brinkworth article reports on a comparison between a ‘standard protein diet’ (15% protein with 55% carbohydrate) and a ‘high protein diet’ (30% protein and 40% carbohydrate) administered to obese subjects with hyperinsulemia.

Well, the first remark that can be made here is that this is not a test of a LOW carbohydrate diet. But even if it were the results would do nothing for Crowe’s case because the patients achieved weight loss on both diets but noticeably more on what is here called a high protein diet (S.P. -2.9+/-3.6 % HP -4.1+/5.8%). However, it seems to have been a poor test altogether because the authors report that after an initial period the protein intake decreased in the HP-diet and increased in the SP-diet so that at week 68 there was little difference. Adherence in both groups was poor.

Yet with both diets there was an improvement in cardiovascular risk factors.

The Foster article also reports on a comparison, this time of a low carbohydrate, high protein and high fat diet and a low calorie, high carbohydrate diet. Both diets were administered over a year. The low carbohydrate diet showed greater weight loss after six months but not after twelve months.

It should be remarked however that of the high carbohydrate diet was said that it was low calorie whereas this was not the case with the low carbohydrate diet. So was this a fair comparison? Also, the low carbohydrate diet was associated with greater improvement of some risk factors for coronary heart disease (greater increase in HDL cholesterol and decrease in the triglyceride concentration). A fact that does nothing for Crowe’s assertions about the dangers of a low carbohydrate diet for CHD.

The Franz article finally seems to have nothing to do at all with a low carbohydrate diet. The abstract says: “Result shows that weight loss intervention utilizing a reduced energy diet and exercise are associated with moderate wqeight loss at 6 months. Although there is some regain of weight, weight loss can be maintained.”

I will report on the other ones when I have tracked them down.

Good analysis of the studies. One of the tricks foes of the low-carb diet use is to quote studies where the authors of the study purport to study low-carb diets but in reality study diets that are minimally diminished in carbohydrate. Those of us who are familiar with low-carbohydrate diets realize that carbs have to be restricted to at the most 50 g per day. Dropping carbs to 175 g per day from 250 g per day doesn’t do the trick, yet these minimal reductions are reported as low-carb diets.

MRE

http://video.google.com/videoplay?docid=6731102750245618218

Enjoy.

Great fun! Thanks for sending. I’m assuming the position.

MRE