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Author Topic:   Good Calories, Bad Calories, by Gary Taubes
Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 256 of 451 (474039)
07-04-2008 6:08 PM


Correcting Misinformation
Molbiogirl has returned to this thread and resumed her campaign of ridicule, character assassination, error, and misinformation. I guess there's something about the carbohydrate hypothesis that causes irrational and emotional knee-jerk objections, which is no way to contribute to a dispassionate scientific discussion. For Molbiogirl, science and research papers are just a backdrop upon which to paint her canvas of mudslinging and fallacies. There's really no way a rational dialogue can take place while Molbiogirl maintains this malevolent and emotional approach, and so all I can do is correct any misinformation I find in her three recent consecutive messages, Message 253, Message 254, and Message 255.
First, from Message 253:
Molbiogirl in Message 253 writes:
I finally settled on some really obvious flaws (no "temporary fat storage in the liver" after carb digestion, no "elevated VLDL levels" after carb digestion, etc.) to try and drive the point home ... no dice.
Taubes never says anything about "temporary fat storage in the liver". What he says is that the liver produces triglycerides (molecules containing three fatty acids) for temporary storage, and it was me who assumed that storage was in the liver. Molbiogirl corrected me, but since then has continued repeating the false claim that this is something Taubes said, something she knows isn't true since she has Taubes' book in her possession.
Moving on to Message 254:
Molbiogirl in Message 254 writes:
What you have failed to mention is that the reduction in epileptic seizures is accompanied by over 1/3 of the children suffering significant cognitive impairment.
Which you would have known had you watched the Charlie Rose interview (Taubes/Dr. Howard/Dr. Ornish) that I linked earlier in the thread.
Taubes tried to throw the ketogenic diet/epileptic seizure connection in Dr. Howard/Dr. Ornish's face and got a thorough dressing down -- with the facts.
The same mechanism for eliminating the seizures is apparently responsible for seriously degrading cognitive processes.
Molbiogirl misremembers the Charlie Rose nutrition panel discussion (YouTube Video), and this is wrong on two levels. First, it is actually Dr. Barbara Howard who introduces the topic, not Taubes. Second, Dr. Howard, a representative of the American Heart Association which is irrationally opposed to low carbohydrate diets, makes a series of claims that aren't supported by the research, even though she says they are:
Dr. Barbara Howard on the Charlie Rose show at 19:40 writes:
I would challenge Gary strongly about the accuracy of the Atkins data because it is well known that if a person eats very high protein and a lot of fat you become ketotic. As soon as you become ketotic you lose fluid and you lose your appetite, so of course you get a short term weight loss. But no one has ever shown even in a non-randomized trial that that can be sustained. What has been shown is that high protein, the levels of protein that they include in that diet, are absolutely detrimental, to the kidney and to the liver. They cause bone loss, very worrisome for a post menopausal woman, and those diets have been used in children for many years who have epilepsy, and those children show definite cognitive dysfunction."
Notice that Dr. Howard does not say what Molbiogirl claims she did, about "over 1/3 of the children suffering significant cognitive impairment." Dr. Howard mentions no such figures. As to the rest of the claims, it appears that Dr. Howard is confusing ketosis, a normal metabolic process, with ketoacidosis, which is indeed dangerous but has other causes unrelated to low carbohydrate diets.
On this panel, Dr. Barbara Howard and Dr. Dean Ornish are both arguing as if there existed conclusive evidence showing that not only are low carbohydrate diets ineffective, they are dangerous. But the research that actually exists is not consistent with such conclusions, as much as they might wish it were.
Concerning whether a ketogenic diet (a diet high in fat and low in carbohydrates) causes cognitive impairment in children with severe epilepsy, I could not find research studies showing this connection, which is not to claim it doesn't exist, I just couldn't find it, though I did find some urban legend-style misinformation out there on the Internet. And I also found a review study (Ketogenic Diet for the Treatment of Refractory Epilepsy in Children: A Systematic Review of Efficacy) from the journal Pediatrics (published by the American Academy of Pediatrics) that concludes:
"Although controlled trials are lacking, the evidence is sufficient to determine that the ketogenic diet is efficacious in reducing seizure frequency in children with refractory epilepsy."
And about cognitive impairment it says:
Poorly controlled epilepsy has been associated with higher rates of mortality, unemployment, and cognitive impairments.
Possibly Dr. Howard is confusing the remedy with one of the symptoms of refractory childhood epilepsy.
Moving on to Message 255:
Molbiogirl in Message 255 writes:
First, let me say that the New Scientist link you provide is referencing a 2001 paper by Havel. That's kinda funny, donchathink? A 2008 article discussing 7 year old findings?
The article is not about "a 2001 paper by Havel." As it clearly states, "Havel presented the results at a meeting of the Endocrine Society in San Francisco last week." By "last week" they mean mid-June of this year, just a few short weeks ago, not 2001. I can't imagine how Molbiogirl could make such a serious mistake, especially since she actually quotes the article in its entirety (here's the link to the article again: Is fructose fuelling the obesity epidemic?).
So when Molbiogirl goes on to ask:
Second, let me ask: Have you read the full Havel paper?
The answer is, of course, no. This was a presentation at a very recent conference, and the paper hasn't yet been published to my knowledge.
Fourth. I have read the 2001 Havel article.
Except that no "2001 Havel article" is mentioned in the New Scientist article. From the quotes Molbiogirl provides I was able to track the paper down. It is Fructose, weight gain, and the insulin resistance syndrome, and it is a November, 2002 (not 2001), paper that appeared in the American Journal of Clinical Nutrition. I don't know what it was in the New Scientist article that led Molbiogirl to this paper, but it looks very interesting and I will give it a read.
Problem No. 1. The obesity epidemic started long before HFCS was a staple of the American diet. HFCS wasn't developed until 1957. Obesity was already a problem. Remember the Pima!
Obesity has a long history, but the obesity epidemic that affects the entire western world across all religions, races and income categories is considered to have begun in the 1980s. This link contains a series a slides showing the increasing obesity rates by state from 1985 to 1999: The Worldwide Obesity Epidemic. Just start at slide 10 for 1985 and keep clicking for the next slide to see the US turn from mostly non-obese to mostly obese as the years click by. It makes for dramatic watching.
Glycogen. Not fat! (A reminder for those who haven't read the entire thread -- carbs are metabolized into glycogen -- a form of energy that is stored in the muscles and liver that isn't fat.)
This is so oversimplified as to be wrong. Both glucose and fructose are carbohydrates, and fructose is primarily transformed into triglycerides (fatty acids) by the liver. There are also metabolic pathways by which glucose can be transformed into triglycerides. Just baldly stating that "carbs are metabolized into glycogen" is very misleading.
Also, by the way she presents this point Molbiogirl may give some the impression that Taubes in some way claims that it is carbohydrates being digested into fat that causes obesity. Rest assured that this is not part of Taubes argument. While there are indeed metabolic pathways by which carbohydrates can be transformed into fatty acids, Taubes hypothesis is that it is elevated insulin levels caused by the intake of refined carbohydrates that make us fat, because elevated insulin levels increase the update of fatty acids by adipose tissue (fatty tissue).
Huh. Fructose is good for Type 2 diabetics. Taubes would have a fit.
Most components of diet have both positive and negative effects, and fructose is no exception. One of the negative effects of fructose described by Taubes is that because sustained intake at elevated levels (e.g., several cans of HFCS-sweetened beverage per day) can reduce the ability of the liver to transform glucose into glycogen (it's busy transforming fructose into triglycerides), thereby causing glucose to remain at higher levels in the bloodstream which in turn causes the pancreas to churn out more insulin, which causes increased insulin resistance, one of the primary symptoms of metabolic syndrome and diabetes. Molbiogirl can find this on page 200 in Taubes book.
De novo lipogenesis does not increase in response to eucaloric glucose ingestion (31).
Translation of biochem speak: de novo lipogenesis = making new fat. Taubes kinda missed this fact in his "exhaustive" studies.
This contains two errors, the first of which is not Molbiogirl's fault. First, the Havel paper is stating this a bit more strongly than the paper they reference (Regulation of hepatic de novo lipogenesis in humans), which says in the abstract:
The enzymatic pathway for synthesis of fatty acids from acetyl-coenzyme A, or de novo lipogenesis (DNL), is present in human liver and, to a lesser extent, in adipose tissue. Although the molecular and enzymatic regulation of the components for DNL are well characterized, the quantitative importance of the assembled pathway and its physiologic functions have remained uncertain.
The abstract does not describe the results, and the paper is only available for pay, but I did find a very similar paper (De novo lipogenesis during controlled overfeeding with sucrose or glucose in lean and obese women) which concludes, "De novo lipogenesis increases after overfeeding with glucose and sucrose to the same extent in lean and obese women but does not contribute greatly to total fat balance."
Of course, we knew already that this was not a primary metabolic pathway for triglyceride production, but the Havel paper is clearly overstating the case to say that, "De novo lipogenesis does not increase in response to eucaloric glucose ingestion." I think all he was trying really to say is that it is not a primary contributor and need not be given much consideration when identifying sources of triglyceride production sufficiently significant to contribute to obesity. And, of course, Taubes describes these issues correctly in his book.
(In one of the 3 studies) body weight increased in a group of 14 middle-aged men, 11 with type 2 diabetes mellitus and 3 with type 1 diabetes mellitus, who incorporated 50-60 g fructose/d into their diets for 24 wk (38).
14 guys! Most of whom had diabetes. I'm serious. Somebody call the Nobel committee.
Molbiogirl is in a biology PhD program and is well aware of how small the number of subjects is in most studies. Limited sample size is extremely common in the field of diet/health research. There have been some large gold-standard studies, but they are extremely expensive (the country studies cost hundreds of millions of dollars 40 years ago and would cost billions today), so most studies are small. Small sample size will be true of much research literature cited in support of either side of the dietary fat hypothesis.
But one wonders why Molbiogirl is trying to discredit a paper she's using to support her position?
Fructose, unlike glucose, does not stimulate insulin secretion from pancreatic cells (40, 41). ... Although high-carbohydrate meals stimulate leptin production in humans relative to high-fat meals (80), if the carbohydrate provided in this study had been fructose rather than glucose, the results would probably have been different because of the dissimilar effects of the 2 sugars on insulin secretion. To compare the effects of glucose and fructose on leptin production, plasma leptin concentrations were measured in rhesus monkeys after intravenous infusion with saline, glucose, or fructose. Glucose infusion markedly increased plasma glucose and insulin concentrations and progressively increased plasma leptin 4-8 h into the infusions. In contrast, an intravenous infusion of the same amount of fructose only modestly increased plasma glucose and did not stimulate insulin secretion or increase circulating leptin concentrations over an 8-h period (65).
There goes yet another of Taubes' pet theories. He thinks insulin is the driving force behind obesity.
The conclusion that insulin is not a driving force behind obesity does not follow from the quoted passage. Indeed, it doesn't address the causes of obesity at all. This is a frequent occurrence in Molbiogirl posts, to quote something, almost anything it sometimes seems, then claim it somehow supports her position no matter how irrelevant.
Another puzzle for Taubes. How on god's green earth is hyperinsulemia induced without insulin?
As mentioned earlier, this is described on page 200 in Taubes' book.
An increased supply of nonesterified fatty acids in the liver also leads to an increase in the production of VLDL triacylglycerol (102).
Aha! Elevated VLDL correlated with fat! Poor old Taubes. He's getting a licking in this paper.
This requires a little translation. "Non-esterified fatty acids" are free fatty acids. "Triacylglycerol" is the technical term for what is more commonly called triglycerides, which are three fatty acids bound together into a single large molecule for transport around the body in the bloodstream.
The passage Molbiogirl quotes is saying that increasing the supply of free fatty acids to the liver can lead to an increase in the production of VLDL triglycerides, which isn't inconsistent with anything Taubes says. Where Taubes writes about this process in his book he's talking about coronary heart disease, not obesity.
The combination of the high-fat diet with fructose resulted in increased circulating triacylglycerol, and fructose with copper deficiency resulted in significant increases in blood cholesterol.
Uh oh. Looks like one needs both fat and fructose to elevate TAGs. More bad news for Taubes.
Fat plus fructose is only one of the many metabolic pathways that can elevate triglyceride levels.
Hyperlipidemia did not develop when starch was combined with a high-fat diet (110).
Translation of biochem speak: hyperlipidemia = putting on too much fat aka getting pudgy.
And starch = carbs. Nail in the coffin for Taubes, if you ask me.
In other words, this passage says that high levels of triglycerides did not result when starch (carbohydrates) was combined with a high fat diet. This is rather inconclusive, as what's truly significant is insulin levels. The more complex the carbohydrate, the less insulin is released to transform triglycerides into fat, and the passage gives no indication of the degree of complexity of the carbohydrate.
Hellerstein (111) showed that there is little de novo lipogenesis from glucose under eucaloric conditions in humans.
Yet another study Havel mentions that completely destroys Taubes' central argument.
Taubes position is definitely not that "de novo lipogenesis" from glucose is the cause of obesity. Again, where Taubes talks about the liver producing triglycerides from glucose it was in the context of coronary heart disease.
This concludes the correction of errors and misinformation provided by Molbiogirl in her three messages. Molbiogirl is operating under the supposition that the evidence disproving the carbohydrate hypothesis already exists, but it doesn't. And the evidence conclusively supporting the dietary fat hypothesis doesn't exist either. It is this paucity of evidence that Taubes decries most.
Whether the carbohydrate or dietary fat hypotheses are right or wrong will be shown by scientific research and discourse, not by whatever it is Molbiogirl is doing. In other words, in a scientific discussion you have to say things that are about the hypothesis rather than about the people backing the hypothesis, and more importantly, when finally addressing the topic you have to say things that are actually true.
--Percy

Joe T
Member (Idle past 2169 days)
Posts: 41
From: Virginia
Joined: 01-10-2002


Message 257 of 451 (475691)
07-17-2008 1:57 PM


A new Study
On MSNBC (MSN | Outlook, Office, Skype, Bing, Breaking News, and Latest Videos) and CNN there is a report of a study comparing the Mediterranean, low fat and low carb (no fat restrictions) diets. The report will be coming out in the NEJM. Some of the findings:
1. In general low carb beat low fat for weight loss and cholesterol lowering. Note that the fats consumed by the low carb peoples were vegetable based so this probably doesn’t do anything one way or another to settle the Taubes/Atkins claims (as I understand them) that saturated animal fats are not a health issue.
2. Apparently men and women lose weight differently. Women responded better to the Med diet, while men responded better to the low carb diet.
3. Diabetics only lowered their blood sugar on the Med diet.
I would be interested in seeing the NEJM article. Maybe one of the med types here can read it and post some of the details.
BTW I finally found a low carb/high fiber (12 gms) tortilla that more closely resembles food rather than cardboard. I’ll print the brand name when I go home and look at the label. I think that the thing has less than 10 gms net carbs per serving.
Joe T.

Replies to this message:
 Message 258 by Percy, posted 07-17-2008 4:01 PM Joe T has not replied

Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 258 of 451 (475707)
07-17-2008 4:01 PM
Reply to: Message 257 by Joe T
07-17-2008 1:57 PM


Re: A New Study
Hi Joe, thanks for posting this MSNBC article (Low-carb beats low-fat in diet duel). There's a few things I want to comment on, but first a short personal report.
Concerning the state of my diet, I'm now down 15 pounds. I'm losing weight very slowly, and as I've mentioned, I have to do it that way. If I lose weight too fast then I lose stamina, which I can't afford to do. Today the temperature is around 90, and in an hour or so I have to play some tennis, which I do around three times a week. If I eat too little I get too tired too quickly.
Concerning the state of my health, a few weeks ago I had my annual checkup, which includes blood work. My triglycerides, cholesterol, HDL and LDL levels have never been better. They're way better, in fact, best they've ever been in the last 20 years. Before that I have no data.
Now a few comments about the article.
First, here's a link to the actual study itself in the New England Journal of Medicine: Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet. I actually have to leave in a few minutes and can't read it right now.
msnbc writes:
The low-fat diet ” no more than 30 percent of calories from fat ” restricted calories and cholesterol and focused on low-fat grains, vegetables and fruits as options.
If the low-fat diet this study used is typical of modern low-fat diets, then anachronistically enough the low-fat diet still features cholesterol restriction when it's been known for at least 20 years that dietary cholesterol does not become blood cholesterol. Dietary cholesterol is broken down by the digestive system before it reaches the bloodstream. Dietary cholesterol is not the source of blood cholesterol.
The Mediterranean diet had similar calorie, fat and cholesterol restrictions, emphasizing poultry, fish, olive oil and nuts.
So the main difference between the low-fat and the Mediterranean diets used in this study is that the low-fat diet included more carbohydrates. Of the three diets in the study, the low-fat had the highest carbohydrate content and the worst performance for weight loss.
"So not a lot of butter and eggs and cream," said Madelyn Fernstrom, a University of Pittsburgh Medical Center weight management expert who reviewed the study but was not involved in it.
Since Madelyn Fernstrom reviewed the study, she has knowledge of details that may not have been mentioned in the article, but I should mention that butter and eggs contain very little carbohydrates and would not normally be restricted in any way on a low carbohydrate diet. Proportionally cream contains far higher levels of carbohydrates than butter or eggs, but one doesn't normally drink much cream, anyway. Certainly a couple of teaspoons of cream in a cup of coffee is going to contribute negligibly to carbohydrate intake, definitely less than a single gram. Cream or milk in products like ice cream is another matter, since the sugar in such food products results in high carbohydrate levels, including fructose.
More surprising were the measures of cholesterol. Critics have long acknowledged that an Atkins-style diet could help people lose weight but feared that over the long term, it may drive up cholesterol because it allows more fat.
This should come as a surprise only to members of the American Heart Association and the American Diabetes Association, which for reasons known only to themselves choose to ignore the decades of research clearly showing that increased intake levels for fat and protein do not correlate with cholesterol levels. Or with obesity. Or with heart disease, for that matter. Or with diabetes, either.
As far as the American Heart Association goes, I hope its members think of it in the same way American Catholics think about the Pope. It's a good and important organization, it fills an important organizational role, but by and large they're not actually going to follow its dietary advice.
I also wanted to comment on a couple things you mentioned:
Joe T writes:
Note that the fats consumed by the low carb peoples were vegetable based so this probably doesn’t do anything one way or another to settle the Taubes/Atkins claims (as I understand them) that saturated animal fats are not a health issue.
If I could clarify Taubes position on saturated fats (which may or may not be the same as Atkins, I don't know - I don't have the book with me right now, but I don't recall Atkins mentioned in much more than a historical role), he's not saying saturated fats are not a health issue. What he's saying is that they aren't the health issue that the American Heart Association says they are, and there are already many completed research studies calling their position on saturated fats into question. Like most components of diet, saturated fats carry both benefits and risks. High intake levels of saturated fats correlate with higher risk of coronary heart disease (this correlation should not be mistaken for causation, which hasn't been established), while low intake levels correlate with even higher rates of rectal cancer (again, no causation established). Pick your poison. By the way, the risk of death from rectal cancer is higher than that for coronary heart disease.
Taubes also describes some positive dietary contributions of saturated fats. I don't recall the details, and as I said, I don't have the book with me right now.
3. Diabetics only lowered their blood sugar on the Med diet.
This finding is the only one I find surprising. It will be interesting to read the study when I get a chance to see if it contains any speculation about why higher fat intake might boost blood sugar levels.
By the way, the article contains a link to a Newsweek article about the same study (The Never-Ending Diet Wars) by Dean Ornish, who says the study has some serious flaws. Dr. Ornish's name might be familiar to some, he has his own diet called The Ornish Diet, which is a low-fat diet, so naturally he's unhappy with the study's results. I don't have time to give this much of a look right now, either, I'll have to comment later.
--Percy
Edited by Percy, : Clarification in next to last para.
Edited by Percy, : Spelling in last para.
Edited by Percy, : Fix minor grammar mistake.

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 Message 257 by Joe T, posted 07-17-2008 1:57 PM Joe T has not replied

Replies to this message:
 Message 259 by Percy, posted 07-19-2008 9:48 AM Percy has seen this message but not replied

Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 259 of 451 (475864)
07-19-2008 9:48 AM
Reply to: Message 258 by Percy
07-17-2008 4:01 PM


Re: A New Study
Hi all!
I'm replying to myself because I want to follow up on this from my previous message:
Percy writes:
By the way, the article contains a link to a Newsweek article about the same study (The Never-Ending Diet Wars) by Dean Ornish, who says the study has some serious flaws. Dr. Ornish's name might be familiar to some, he has his own diet called The Ornish Diet, which is a low-fat diet, so naturally he's unhappy with the study's results. I don't have time to give this much of a look right now, either, I'll have to comment later.
I've had a chance to read Dean Ornish's Newsweek article and will now comment.
One would expect that someone of Dean Ornish's reputation for integrity and intellect would play things straight up, but Ornish engages in the same kind of shenanigans we see here everyday, for instance:
Dr. Dean Ornish writes:
However, participants in the study who were on the "low-fat" diet decreased their total fat intake from 31.4 percent to 30.0 percent, hardly at all.
To say that participants on the low-fat diet reduced their fat intake "hardly at all" is misleading in the extreme. Participants on the low-fat diet reduced their fat intake by more than those on either the Mediterranean or low-carbohydrate diets. Low-fat dieters reduced their fat intake by 18.9 grams/day, with Med dieters next at a 10.5 grams/day reduction, and low-carb dieters bringing up the rear at a 1.7 grams/day reduction. In other words, low-fat dieters reduced their fat intake far more than those on the other two diets.
What does Dr. Ornish base his figures upon? He drew them from this table: Changes in Dietary Intake, Energy Expenditure, and Urinary Ketones during 2 Years of Intervention
The 31.4% and 30.0% figures are "percent of total energy contribution". Because total energy intake was reduced (these *are* diets, after all), a lower fat intake contributed roughly the same percentage of total energy for the low-fat diet. If you look at the columns for the other diets, Med-diet participants increased their percentage fat intake slightly, while low-carb participants increased it from 32.1% to 39.1%. But dieters on all plans reduced their fat intake, with low-fat dieters having by far the greatest reduction.
Dr. Dean Ornish writes:
I'm also very skeptical of the quality of data in this study. For example, the investigators reported that those on the "low-fat" diet consumed 200 fewer calories per day”or 10,000 fewer calories per year”than those on the Mediterranean diet, yet people lost more weight on the Mediterranean diet. That's physiologically impossible.
Aside from his bad math (200 calories/day at 365 days/year is 73,000 calories, not 10,000), Dr. Ornish is evidently a member of the "a calorie is a calorie is a calorie" camp. I've said enough about this fallacy in this thread already, but I'd be glad to go over it again with anyone who's interested. As long as Dr. Ornish adheres to this fallacy he'll be unable to perceive the evidence before his very eyes.
Dr. Ornish is critical of the low-fat diet used in the study, referring to it in quotes, because is does not include a significant enough reduction in fat. The Ornish diet advises larger reductions in fat intake, and so Ornish believes, correctly I think, that the study does not reflect on the Ornish diet.
Dr. Dean Ornish writes:
My colleagues and I at the nonprofit Preventive Medicine Research Institute and the University of California, San Francisco, have studied for more than three decades the effects of diets much lower in fat (10 percent) than the one used in NEJM study as well as lower in refined carbohydrates and higher in fruits, vegetables, whole grains, legumes and soy products.
I'm not familiar with the Ornish diet, but from this description it sounds like a pretty good diet, particularly the part about reducing intake of refined carbohydrates.
Dr. Ornish goes on to describe studies conducted by his non-profit that demonstrate the effectiveness of the Ornish diet, but his earlier sloppiness with numbers means I'd have to actually read the studies before I'd accept his claims. Since I don't have that kind of time right now I'll withhold comment on his studies and just say that Dr. Ornish and I would probably agree that this recently concluded study cannot be used to judge the Ornish Diet. But we definitely appear to agree that it is great evidence by which to judge the dietary recommendations of the American Heart Association - they're a failure.
Dr. Ornish cites two studies which he says indicate that low carbohydrate diets worsen heart disease, but I don't have time to look at them right now. The studies are:
Dr. Ornish argues that studies that measure actual heart disease rates rather than risk indicators for heart disease are better, and I agree with him. He also argues that there is still a great deal of debate about HDL, and that the higher levels of HDL that result from a low carbohydrate diet are not necessarily an indicator of good health, and I agree with this also, in the sense that research is currently inconclusive on this point.
When you go for your annual checkup as I recently did your doctor will review with you various biomarkers, most prominent among them HDL/LDL cholesterol levels and triglyceride levels. I think Ornish's point is that these biomarkers are not necessarily reliable as indicators of good health, and I again agree that current research is not conclusive. Taubes would likely agree, too. But as any doctor's visit will confirm, these are the indicators that the medical establishment currently thinks are most important, and the three diet study includes this table: Changes in Cholesterol and Triglyceride Biomarkers According to Diet Group during the Maximum Weight-Loss Phase (1 to 6 Months) and the Weight-Loss Maintenance Phase (7 to 24 Months) of the 2-Year Intervention.
The table shows that the low carbohydrate diet beats the other two diets handily for HDL cholesterol, triglycerides and the cholesterol/HDL ratio, and comes in second for LDL cholesterol behind the Mediterranean diet. The low fat diet comes in last in all categories, though there's a near tie in one category.
If HDL/LDL cholesterol and triglycerides are what doctors are going to annually lecture us about, but the research isn't conclusive about whether or not these are relevant biomarkers or not, then what confidence can this give us about the current state of most diet/health recommendations? As Michael Pollan, author of The Omnivore's Dilemma, once said, the state of diet/health research today reminds him of the state of science in the 1650's.
This should not be construed as a condemnation or even a criticism of the medical research establishment. Like the alchemists of the Middle Ages trying to turn lead into gold, they are guilty only of grossly underestimating the task before them.
Dr. Ornish concludes by making some general dietary recommendations that I agree with, and Taubes would likely agree, too, but Taubes would also likely add the wrinkle that sustained intake of heightened levels of refined carbohydrates over long time periods cause changes in metabolism that are very difficult to overcome.
--Percy

This message is a reply to:
 Message 258 by Percy, posted 07-17-2008 4:01 PM Percy has seen this message but not replied

Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 260 of 451 (476867)
07-27-2008 3:01 PM


A Third Possibility
This thread on Taubes book has turned into a debate between the dietary fat and carbohydrate hypotheses, but I recently came across a third hypothesis. Could it be that all these factors play a role?
Before describing this third hypothesis, a brief update on the diet. I'm now down 17 pounds. What's amazing isn't the weight loss itself, but the way it was achieved. Traditional diets are what I call willpower diets, a constant battle between hunger and willpower. But you don't get hungry on a low carbohydrate diet, and that's what's amazing. I've lost all this weight without getting hungry.
The only drawback I've encountered is monotony - the dietary choices of a low carbohydrate diet do not include a lot of variety. Nothing with sugar (0 grams/day isn't really possible unless one gets really anal about dieting, but I'm probably less than 15 grams/day), nothing with bread, nothing with pasta. We tried whole-grain pasta for a while, but when we gave it up was when I broke out of my plateau a few weeks ago, and I've concluded that whole-grain pasta represents an insignificant improvement over regular pasta. I'm already pretty certain that modern versions of whole-grain bread are very little different than their refined grain cousins.
Now, on to this third hypothesis. The July 12, 2008, issue of New Scientist includes an article titled Rewriting Darwin: The new non-genetic inheritance. It says:
New Scientist writes:
It has become increasingly clear that environmental factors, such as diet or stress, can have biological consequences that are transmitted to offspring without a single change to gene sequences taking place.
...
The implications for public health could also be immense...For example, non-genetic inheritance might help explain the current obesity epidemic...
In other words, perhaps the obesity epidemic is explained not by what people are eating now, but by what their parents were eating decades ago. The article concludes with a discussion of this possibility:
Nutrition does seem to have some lasting effect, according to a study by Marcus Pembrey of the Institute of Child Health at University College London and his colleagues. They analysed records from the isolated community of —verkalix in northern Sweden and found that men whose paternal grandfathers had suffered a shortage of food between the ages of 9 and 12 lived longer than their peers (European Journal of Human Genetics, vol 14, p 159). A similar maternal-line effect existed for women, but in this case by far the biggest effect on longevity of the granddaughters occurred when food was limited while grandmothers were in the womb or were infants. It would appear that humans thrive on relatively meagre rations, and the team concluded that under these conditions some sort of key information - perhaps epigenetic in nature - was being captured at the crucial stages of sperm and egg formation, then passed down generations.
Pembrey's team also looked at more recent records from the UK, collected for the Avon Longitudinal Study of Parents and Children. They identified 166 fathers who reported starting smoking before the age of 11 and found that their sons - but not their daughters - had a significantly higher than average body mass index at the age of 9.
Also in 2006, Tony Hsiu-Hsi Chen at the National Taiwan University in Taipei and colleagues reported that the offspring of men who regularly chewed betel nuts had twice the normal risk of developing metabolic syndrome during childhood. Betel nuts are also associated with several symptoms of metabolic syndrome in chewers including increased heart rate, blood pressure, waist size and body weight.
The mother's nutrition might affect a child's risk of obesity, too. Women in the Netherlands who were in the first two trimesters of pregnancy during a famine in 1944 and 1945 gave birth to boys who, at 19, were much more likely to be obese.
All these results raise an important question. Why should factors like food intake or smoking around the time sperm or eggs are created, or at the embryo stage, have such an influence on a child's metabolism and weight?
Extended periods of too much or too little food might trigger a switch to a pattern of gene expression that results in earlier puberty and so earlier mortality, says Pembrey - and this might be heritable. "The reason why some people gain weight more easily is because their metabolic genes are used differently," says Reinhard Steger at the University of Washington in Seattle. He suggests that long before the emergence of modern humans, a network of metabolic genes evolved that was honed for a relative scarcity of food, but not feast or famine. "These genes have become epigenetically programmed during the early stages of life in response to adverse environmental conditions - such as feast. This might explain the current epidemic of type II diabetes and obesity in the west, where food is plentiful." Prolonged epigenetic silencing in response to the environment might also lead to a DNA change that "locks in" epigenetic marks, Steger suggests.
Though not a possibility mentioned in the article, I think the same epigenetic factors (heritable changes passed on by means other than DNA) may have been at work in another substantial change observed in the health of western civilization over the course of the 20th century, that of increasing stature. Much of the 20th century was a period during which children became increasingly larger and taller (not fatter) than their parents. Perhaps the increasing nutritional quality of parents turned on genes responsible for increases in stature. Then in the late twentieth century beginning in the 1970s, increased intake of refined carbohydrates caused other epigenetic changes responsible for increases in obesity and diabetes II in succeeding generations.
Interestingly, this epigenetic possibility could explain the Pima. Increased intake of refined carbohydrates during the late 19th century caused epigenetic factors to turn on genes that made the population more obese and diabetic. It would be interesting to see if the cycle could be broken by one generation following a low carbohydrate diet. Would the next generation have less of a problem with obesity and diabetes?
Ultimately, the answers to the obesity and diabetes epidemics will not be simple. Dietary fat plays a role. Carbohydrates play a role, particularly refined carbohydrates. And while it's still very early in the research cycle, my bet is that epigenetic factors also play a role. The net contribution of each to the problem also remains to be seen, and likely that is complicated, too, with it varying widely across regions, races and segments of society.
--Percy
Edited by Percy, : Punctuation.

Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 261 of 451 (479018)
08-23-2008 8:48 AM


A Possible Neurological Component
Dr. Zane Andrews of Monash University (Australia) has just published research in Nature describing a possible neurological contribution to adult-onset obesity. According to a news release from Monash Univerity:
Dr Andrews found that appetite-suppressing cells are attacked by free radicals after eating and said the degeneration is more significant following meals rich in carbohydrates and sugars.
"The more carbs and sugars you eat, the more your appetite-control cells are damaged, and potentially you consume more," Dr Andrews said.
Full article: Killer carbs - Monash scientist finds the key to overeating as we age
For those with a subscription to Nature, here's a link to the full article: UCP2 mediates ghrelin's action on NPY/AgRP neurons by lowering free radicals
Diet update: I've been plateaued the last couple weeks at about 19 pounds down. Except for the lack of variety the low carb diet continues to be a very easy diet to follow.
I know that anecdotal information says that recidivism is the same for both low fat and low carb diets, but I'm finding that hard to believe. Hunger is the problem with low fat diets. While the desire for foods forbidden on low-carb diets, such as anything with sugar, does have some power, it can't hold a candle to hunger. Take away a special food that I haven't had in a long time and I might become peeved, but deny me food while ravenous and violence is a definite possibility. Hunger wears down the will and overcomes rationality, and there's no hunger on a low carb diet.
--Percy

Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 262 of 451 (482842)
09-18-2008 10:55 AM


Status of the Diet and a Few Observations
So the diet is 5 months old and I'm down 21 pounds! Hurray!
Here are a few observations.
I think that putting the "low carbohydrate" label on my diet is inaccurate, and I think this is true of most reasonable low carbohydrate diets. What the "low carbohydrate" label actually means is low levels of refined carbohydrates, such as sugar and refined flour products like bread and pasta. Many sources of complex carbohydrates are fine, and most low carbohydrate diets explicitly recommend them, such as many vegetables and fruits. Examples of vegetables and fruits that are usually explicitly excluded from low carbohydrate diets are corn and grapes, but many others are just fine.
I've mentioned this one before, but it bears repeating: you don't get hungry on a low-carbohydrate diet if you include meat.
The big danger to dieters is from refined carbohydrates that cause insulin spikes that sweep any available free fat in the bloodstream into fatty tissues.
And the most dangerous form of refined carbohydrates is high fructose corn syrup, a common sweetener used in both carbonated beverages and candy.
While the research is still inconclusive at this point, the possibility that the current diabetes epidemic that is affecting all income groups, races and religions is caused by wearing out the pancreas by subjecting it to frequent and high demands for insulin through the intake of refined carbohydrates must be given serious consideration. If you don't like the prospect of sticking yourself with needles for the rest of your life then you should immediately and drastically reduce your consumption of food products that have significant levels of refined carbohydrates. This includes the aforementioned soda and candy, and also any bread or pasta products made from refined flour.
I don't believe bread or pasta in any form can be part of any effective low carbohydrate diet targeted at weight reduction. This includes even 100% whole grain products. Wheat grain kernels have three components: the kernel shell which is fiber, also called bran, i.e., indigestible carbohydrates; the embryo, also known as wheat germ; and the endosperm which provides nutrition for the embryo when it is planted and begins growing. The endosperm portion is by far the largest. Removal of the bran and germ leaves just the endosperm, which is what makes refined flour. Whole wheat products contain almost as much endosperm as refined flour products. This is mitigated somewhat by the presence of fiber from the bran, but not much, at least not in my experience, your mileage may vary. Best to avoid all breads and pastas in all forms.
--Percy

Replies to this message:
 Message 263 by Joe T, posted 09-18-2008 1:33 PM Percy has replied

Joe T
Member (Idle past 2169 days)
Posts: 41
From: Virginia
Joined: 01-10-2002


Message 263 of 451 (482856)
09-18-2008 1:33 PM
Reply to: Message 262 by Percy
09-18-2008 10:55 AM


Re: Status of the Diet and a Few Observations
Glad your weight loss program is going well. You said something with which I take small exception:
quote:
I don't believe bread or pasta in any form can be part of any effective low carbohydrate diet targeted at weight reduction. This includes even 100% whole grain products.
My experience of loosing 35 lbs over a 1 year period (and keeping it off for the last 2 years) is that you (meaning me) can have a reduced carb diet, lose weight, and eat smaller (1/3 to 1/2 cup servings) amounts of whole grains (bread, pasta, rice, barely, bulgur wheat, etc). I also eat grapes and bananas which some low carb diets consider anathema.
I also lost considerable weight once in my youth (mid to late thirties) on a high carb diet, but that involved unrealistic levels of exercise. Once the 10-15 hrs/week in the gym tailed off, the weight piled on. I had to adjust my diet to reduce carbs as I got older and busier to get the weight back off and keep it off.
Joe T.

This message is a reply to:
 Message 262 by Percy, posted 09-18-2008 10:55 AM Percy has replied

Replies to this message:
 Message 264 by Percy, posted 09-18-2008 2:06 PM Joe T has not replied

Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 264 of 451 (482864)
09-18-2008 2:06 PM
Reply to: Message 263 by Joe T
09-18-2008 1:33 PM


Re: Status of the Diet and a Few Observations
Joe T writes:
My experience of loosing 35 lbs over a 1 year period (and keeping it off for the last 2 years) is that you (meaning me) can have a reduced carb diet, lose weight, and eat smaller (1/3 to 1/2 cup servings) amounts of whole grains (bread, pasta, rice, barely, bulgur wheat, etc). I also eat grapes and bananas which some low carb diets consider anathema.
No arguments here. The most important criteria of all is what works for us personally. Each of us is our own experimental laboratory building up databases full of dos and don'ts.
I guess I'm hoping this thread successufully communicates two significant points:
  1. As far as existing research is able to indicate, low carbohydrate diets are as safe as low calorie diets. Characterizations of low carbohydrate diets by organizations like the American Heart Association and the American Diabetes Association as dangerous quackery have no basis in existing research. In fact, if these and other organizations are correct in believing that lower triglyceride levels and higher HDL/LDL ratios are desirable for good health, then the research already indicates that low carbohydrate diets are healthier than low calorie diets.
  2. For those who find low-calorie diets difficult to follow because of hunger, a low carbohydrate diet that has a significant meat component will greatly alleviate, even eliminate, the hunger problem. My label for low calorie diets is "willpower diets", because such diets will only last as long as willpower can hold out against hunger.
There's an interesting article in today's New York Times about how people are dieting less now than 20 years ago and focusing more on seeking out healthy foods rather than avoiding bad foods, in other words, focusing on inclusivity instead of exclusivity: Instead of Eating to Diet, They’re Eating to Enjoy
--Percy

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 Message 263 by Joe T, posted 09-18-2008 1:33 PM Joe T has not replied

Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 265 of 451 (487006)
10-26-2008 6:49 PM


Status of the Diet, and a Couple Observations
So the diet is 6 months old and I'm down 26 pounds! Hurray!
One thing that became apparent this past month was that I was no longer losing weight on the amount of food that had allowed me to lose weight before. I had plateaued for a few a weeks around 21/22 pounds down, but once I recognized this I reduced the amount I eat by maybe another 20% and resumed losing weight.
I can't give calorie or carbohydrate estimates because I keep track of neither, but as I've been saying in this thread, I try to eat no refined carbohydrates whatsoever, meaning no sugar and no refined grain products such as bread or pasta. As a practical matter that's not really possible, but it's probably less than 10 grams/day, certainly less than 20. My diet is a bit monotonous as I eat mostly vegetables and meat, maybe a 50/50 mix, and some nuts, too. There's also a fair amount of fat in my diet from sources like regular salad dressing, butter and cheese. When I reduced the amount I eat I had to increase fat intake because I find it effective at holding off hunger.
One other observation has to do with exercise. I engage in vigorous exercise several times a week, and I have no trouble maintaining energy levels on this diet. My ability to exercise appears to be neither better or worse.
I miss pizza, cheesesteaks, subs, calzones, lasagne, even just a simple ham and cheese sandwhich. I'm eagerly looking forward to the end of my diet, but I don't have a specific target weight. When I reach a weight below which I shouldn't go I have a feeling my body will tell me, but I would be surprised if I end up losing more than 40 pounds. After I finish the diet comes the big question: can I keep the weight off?
--Percy

Replies to this message:
 Message 268 by Michamus, posted 04-08-2009 11:03 AM Percy has replied

Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 266 of 451 (493808)
01-10-2009 10:06 PM


Evolving Views on Refined Carbohydrates
That refined carbohydrates are bad for you may be a view that is quitely moving more and more into the mainstream. It's too early to be sure, but a couple recent articles are heartening. Our local paper recently ran an article about diabetes in the Latino community that had this to say:
Latinos are known to have a diet rich in rice, beans and potatoes, such meals are high in carbohydrates, which, after broken down, translate to increased flow of sugar in the blood stream.
This is encouraging because of the lack of emphasis placed by the American Diabetes Association on the diabetic risks associated with carbohydrates. Hopefully it is only a matter of time before the ADA begins issuing forceful warnings, but in the meantime local health officials seem aware of the dangers.
The January, 2009, issue of Scientific American also got into the act with this passing comment in a SciAm Perspectives article about evolution:
Scientific American writes:
Many modern diseases - obesity, diabetes and autoimmune disorders - come about, in part, because of the mismatch between our genes and an environment that changes more quickly than human genomes can evolve. Understanding this disparity may help convince a patient to make a change in diet to better conform to the demands of a genetic heritage that leaves us unable to accommodate excess, refined carbohydrates and saturated fats from a steady intake of linguine alfredo and the like.
Taubes couldn't have said it better himself!
Increasingly in grocery stores one sees growing recognition of the dangers of refined carbohydrates, as the shelves more and more often offer low-carbohydrate substitutes. Good to see.
Concerning the diet, the more I lose the slower I lose, but I'm down 28 pounds now.
--Percy

Replies to this message:
 Message 267 by Michamus, posted 04-08-2009 10:58 AM Percy has seen this message but not replied

Michamus
Member (Idle past 5157 days)
Posts: 230
From: Ft Hood, TX
Joined: 03-16-2009


Message 267 of 451 (505165)
04-08-2009 10:58 AM
Reply to: Message 266 by Percy
01-10-2009 10:06 PM


Re: Evolving Views on Refined Carbohydrates
Refined Carbohydrates such as High Fructose Corn Syrup and refined sugars (Found commonly in American-made soft and fruit drinks) should definitely be avoided, or at least minimized. I don't know of any dietitians that would say otherwise.
There is certainly merit in the input to ouput ratio when it comes to energy (food). It is surprising to many people that some of the most fit people (Olympic athletes, and Infantrymen ) actually consume more food than the average American, period. This is to a scale or ratio. This is entirely due to the fact that you require more energy when your activity level increases. You will also notice that healthier individuals seek a more balanced diet.
[red]***Anecdote Alert***[/red]
This isn't to say that our bodies aren't individualized. I for one eat a much larger ratio of meat when compared to my diet than most people. I have been told this isn't healthy, but I have an innate craving for the larger supplement of meat. This also hasn't affected my ability to perform in my tasks here in Afghanistan as an Infantry Medic.
[red]***Anecdote Alert***[/red]
The best solution I can provide for obesity is a balanced diet, and a strict exercise regimen. I have personally seen individuals 40+lbs overweight go through Basic and AIT coming out having come down 20+lbs. I would say anyone that argues against a balanced diet and exercise is probably trying to sell you something, or rationalizing complacency.
Just my two cents.

This message is a reply to:
 Message 266 by Percy, posted 01-10-2009 10:06 PM Percy has seen this message but not replied

Michamus
Member (Idle past 5157 days)
Posts: 230
From: Ft Hood, TX
Joined: 03-16-2009


Message 268 of 451 (505166)
04-08-2009 11:03 AM
Reply to: Message 265 by Percy
10-26-2008 6:49 PM


Re: Status of the Diet, and a Couple Observations
One thing that became apparent this past month was that I was no longer losing weight on the amount of food that had allowed me to lose weight before. I had plateaued for a few a weeks around 21/22 pounds down, but once I recognized this I reduced the amount I eat by maybe another 20% and resumed losing weight.
This is one way to handle a plateau. I would have suggested simply changing the types of food you are eating just to randomize, so as to prevent a memory for your body to go off of. Obviously it is working for you, so keep it up.

This message is a reply to:
 Message 265 by Percy, posted 10-26-2008 6:49 PM Percy has replied

Replies to this message:
 Message 269 by Percy, posted 04-08-2009 2:43 PM Michamus has not replied

Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 269 of 451 (505182)
04-08-2009 2:43 PM
Reply to: Message 268 by Michamus
04-08-2009 11:03 AM


Re: Status of the Diet, and a Couple Observations
My initial goal when I opened the thread was to make people aware of a hypothesis drawing increasing attention that it isn't fat causing the diseases of western civilization (obesity, diabetes and heart disease) but carbohydrates. I didn't originally plan on starting a diet, but I did, so I began posting my progress on the diet here, too.
Current diet status is that I'm on a plateau at 26 pounds down. The big problem with diets isn't finding ones that work. Tons of different diets will work. The problem is finding one you can live with for the long term. Any diet that is based upon deprivation enforced via willpower will not work for most people for the long term. Some people have that kind of willpower, and I'm sure all our hats go off to them, but most of us don't. That's why a low carbohydrate diet is so important, because it eliminates one of the strongest forces for breaking down willpower: hunger.
Exercise for weight reduction has just as spotty a record as diets. If you're making yourself exercise instead of exercising because you enjoy it, then at some point you'll just stop. Every January my club overflows with an influx of the recently resolved, and most are gone by March.
--Percy

This message is a reply to:
 Message 268 by Michamus, posted 04-08-2009 11:03 AM Michamus has not replied

Dr Jack
Member
Posts: 3514
From: Immigrant in the land of Deutsch
Joined: 07-14-2003
Member Rating: 8.7


Message 270 of 451 (505189)
04-08-2009 4:52 PM


A though: cyclical dieting
This is more a thought than any kind of researched analysis.
I suspect the best form of diet (for weight loss) is one in which you cycle fat/carbs/protein as the major energy providing part of your food on a relatively short time scale (probably switching every 3-4 days; although it might be more practical to use a weekly cycle). The reason for thinking this is that the cells in your stomach take several days to adapt to a new diet.
In experiments in mice it takes 3 days in mice for epithelial cells to be switched for ones adapted to digesting food from a new diet, before this time they fail to extract the full calorific value of the food from the diet, and a large potion it passes undigested out the other end of the gut. It might causes you unpleasant bowel problems as a result, I suppose, but I expect with a little practice it could be tuned reasonably well.

Replies to this message:
 Message 271 by Percy, posted 04-08-2009 5:07 PM Dr Jack has not replied

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