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Eat Fat, Get Thin?

I recently received an e-mail from a high school science department head who is teaching a unit on nutritional science. He asked for my opinion of a YouTube video of a lecture advocating a high saturated fat diet. The speaker is Donald W. Miller, Jr., M.D., a cardiothoracic surgeon at my alma mater, the University of Washington. My correspondent commented, “I have a feeling that there is room for some skepticism.”   I agree: there’s a whole lot of room for skepticism.

An article based on that video lecture is available on Dr. Miller’s website.   It’s entitled “Enjoy Saturated Fats, They’re Good for You!”  If you want to judge for yourselves, I recommend the article over the video, as he is a poor public speaker.

Dr. Miller’s website contains a lot of disturbing material.  He appears to be a contrarian who disagrees with the consensus of scientific experts on a wide variety of topics, for instance:

  • Health Benefits of a Low-Carbohydrate, High-Saturated Fat Diet
  • Fighting Fluoride [fluoride is poison!]
  • Cardiac Surgeon Dr. Donald Miller Tells Dr. Dean Ornish to Take a Hike
  • Avoid Flu Shot, Take Vitamin D [flu is a Vitamin D deficiency disease?]
  • Questioning HIV/AIDS, Human-Caused Global Warming, and other Orthodoxies in the Biomedical Sciences
  • A User-Friendly Vaccination Schedule [no vaccinations before age 2, no live vaccines, etc.]

He refers to questionable sources of information like the Weston Price Foundation and the notorious AIDS denialist Peter Duesberg.

Based on the company it keeps, it would be tempting to write off his diet advice as crankery.  But I tried to ignore who was saying it and give a fair hearing to what he was saying. He begins by attacking the lipid hypothesis: the idea that fat in the diet causes elevated blood cholesterol which causes cardiovascular disease. This no longer needs attacking: mainstream recommendations have followed the evidence and have evolved from a low cholesterol diet to a low fat diet to a low saturated fat diet to avoidance of trans-fats and of excess calories from fat.  He echoes Gary Taubes’ low-carb arguments and his contention that government recommendations to avoid fat led to higher carbohydrate intake and thereby caused the obesity epidemic. That may be true, but it doesn’t justify his conclusion that the solution to the obesity epidemic is to replace carbohydrates in the diet with saturated fat.

He relies on epidemiologic data and evolutionary arguments to show that dietary fat is good: he says that breast-fed babies get high-fat milk, Eskimos and the Maasai eat a high-fat diet and don’t develop CVD (cardiovascular disease), the paleolithic diet was high in fat, and our genome has evolutionarily adapted to a high fat diet. In fact, the groups he cites do develop CVD, although they have a low incidence. He conveniently fails to consider any other possible explanations for why people like the Maasai might have less CVD: they are thin, get a lot of strenuous exercise, have different genes, and have a low life expectancy, often dying of infectious disease and trauma before they are old enough to have developed signs of heart disease.

He says protein is bad for you in excess: it causes nausea, diarrhea, etc.  He repeats  Gary Taubes’ arguments  to demonize carbohydrates.  He prefers fat, particularly saturated fat, and recommends it constitute 70% of our diet.

His epiphany came from reading an article in Nexus in 1999 that led him to question Dean Ornish’s low fat advice. He was further influenced by the book Eat Fat, Lose Fat by Mary Enig and Sally Fallon (co-founders of the Weston A. Price Foundation, which has been criticized by medical experts as purveying misleading information) and by the writings of notorious cholesterol denialist Uffe Ravnskov.

He cites data from the Framingham study showing that over age 50, there is no effect of either high or low cholesterol levels on mortality except for those whose cholesterol level is falling: for every 1% drop in cholesterol levels, there is an 11% increase in all-cause mortality. He doesn’t mention that the same study showed a robust correlation of cholesterol levels with mortality below age 50, and that the authors said the data for those over 50 is confounded by people whose cholesterol levels are not stable, but falling — perhaps due to diseases predisposing to death.  He cites an article by Castelli allegedly showing that increased saturated fat, cholesterol and calories in the diet are associated with decreased blood cholesterol and that people who ate more cholesterol, saturated fat and calories had lower weight and increased activity levels.  This was not an original study but a commentary accompanying an article about The Seventh Day Adventist Health Study showing that, in vegetarians who ate nuts and whole wheat bread, greater nut consumption was correlated with lower CVD mortality. In fact, Seventh Day Adventists have lower blood cholesterol levels, lower fat consumption, and lower mortality rates than the general population.

His is not a fair assessment of the literature, but an exercise in cherry-picking and confirmation bias. The consensus of experts who have reviewed all the published evidence is that high blood LDL cholesterol is a major risk factor for CVD and that lowering it reduces risk, with a greater effect on those with multiple risk factors.

He says, “A hundred years ago less than one in one hundred Americans were obese and coronary heart disease was unknown.”  It was hardly unknown, although it was admittedly less prevalent and may not have been diagnosed with that name. He is correct that obesity has become a serious problem and is a risk factor for diabetes, heart disease, and a number of other illnesses; but he goes too far when he claims

  • that it has been “proven” that CVD, diabetes, and cancer are nutrition diseases;
  • that a low fat/hi carb diet is a human-made disaster comparable to wars and economic meltdowns and to natural disasters like hurricanes, the Ice Age and asteroid impacts;
  • that soda pop trucks are Weapons of Mass Destruction.

He plays the conspiracy card.  He says that scientists who question state-sanctioned paradigms like low fat diets, mutations as a cause of cancer, and HIV as a cause of AIDS are denied grants and silenced. In fact, some of them are very loud for people who have been “silenced,” and they may have been denied grants simply because their research was not as worthy as competing grant proposals.

Taubes says as long as you avoid carbs you can eat all the protein and fat you want and not gain weight. Miller goes even further, claiming that a high fat diet will make you lose weight. I think any influence on weight loss is due to a decrease in calorie intake; admittedly, the satiety from fat might reduce total calorie consumption, but this has not been proven to have any practical effect on dieters.

Miller says

The ideal caloric ratio between carbohydrates, fats, and protein is carbohydrates, 10-15 percent; proteins, 15-25 percent; and fats, 60-70 percent of calories, with the majority of them being saturated fats. Among the different kinds of fats, saturated fats and monounsaturated fats are good; except for omega-3 and a small amount of omega-6 essential fatty acids, polyunsaturated fats are bad in the high quantities that they are eaten in a Western diet, particularly industrially processed vegetable oils; and trans fats are terrible. Saturated animal fat is best obtained from grass-fed beef and pastured chickens, along with nitrate-free, additive-free bacon and sausage; and seafood from wild, not farm-raised, fish.

Some of this sounds like ideology based on the natural fallacy. He starts each day with two tablespoons of coconut oil. He claims that eggs from pastured poultry are much richer in nutrients, that organic isn’t good enough, and that the “Sacred Cow” transforms green grass and sunlight into vitamins A, D, and K and that this process is enhanced when cows are contented, grass fed, and not confined. He cites no peer-reviewed studies as evidence for these claims, but cites his own articles and podcasts and unreliable books by Enig and Ravnskov, and he shows a video of Julia Child talking about how much she liked the French fries from McDonald’s when they were deep-fried in lard. In passing, he mentions that aspartame is neurotoxic and causes obesity; I think he’s wrong about that.  He also links Alzheimer’s to a deficiency of saturated fat and asthma to a lack of the dietary fat needed to make lung surfactant.

He says:

Saturated fats work best for losing weight. In a randomized, double-blind trial comparing the effects of coconut oil and polyunsaturated vegetable (soybean) oil in women with abdominal obesity, women who consumed coconut oil had a significant reduction in waist circumference (with no change in cholesterol levels). Women taking vegetable oil had no change in their waist size and had a statistically significant increase in LDL cholesterol and reduction in HDL cholesterol (Lipids 2009;44:596–601).

This is cherry-picking and misrepresentation. The study doesn’t support his claim: it was a small trial and in fact it showed no difference in weight, but only a change in waist circumference.

Miller manages to ignore the mountain of data that resulted in the current recommendations for the prevention and treatment of heart disease. It is probable that the dangers of saturated fat have been exaggerated, but no reputable cardiologist would claim that saturated fat is good for you or that fat should make up 70% of the diet. Cardiologists have become more liberal about allowing some cholesterol and fat in the diet, but they still consider fat intake as part of the complex equation of risk factors. Fat contains 9 calories per gram compared to 4 calories per gram for protein and carbohydrates, and the calories can add up fast to contribute to weight gain.

Serendipitously, I have on my desk an uncorrected proof of a book by two cardiologists that is scheduled for publication in January.  They mention that recent studies have questioned the saturated fat/CVD link but they suggest that those studies only compared one unhealthy diet to another. Reducing saturated fat in the diet is not good for the heart if you replace the fat with refined carbohydrates and more calories. The heart-healthy diet that is supported by the best evidence is the Mediterranean diet, although even there the evidence isn’t perfect, because no good controlled prospective studies have been done to show that switching to that diet actually reduces mortality. They recommend avoiding trans fats and limiting eggs, fatty meat, saturated fat, and salt, consistent with the guidelines of the American Heart Association and every other credible source of diet advice.

I see Dr. Miller as an example of an oft-repeated pattern. A conventional doctor becomes frustrated with his inability to help some of his patients, and he becomes seduced by an overly simplistic answer based on anecdote and speculation; then confirmation bias does the rest.  He convinces himself that his new treatment plan is working. He cherry-picks the literature, writes books and articles, proselytizes to the world, imagines conspiracies against the Truth he has found, and generally becomes far more enthusiastic than the evidence warrants.  He is sure he is right, and considers his experience proof enough; whereas a true scientist entertains other possible explanations, engages in meaningful debate with peers who disagree, and even tries to prove himself wrong. Listening to Miller gave me déjà vu all over again, and made me feel rather sad.

 

Posted in: Nutrition

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52 thoughts on “Eat Fat, Get Thin?

  1. tuck says:

    “The heart-healthy diet that is supported by the best evidence is the Mediterranean diet, although even there the evidence isn’t perfect, because no good controlled prospective studies have been done to show that switching to that diet actually reduces mortality.”

    That’s a rather confused sentence. According to the first half of the sentence, the “best evidence” support the Mediterranean diet, and according to the second half, “no good controlled prospective studies have been done to show that switching to that diet actually reduces mortality.”

    So that’s really no evidence at all, isn’t it?

    This is ignoring the fact that no-one in the Mediterranean actually eats what’s known as the “Mediterranean diet” in medical circles…

  2. cervantes says:

    It’s actually fairly conventional wisdom right now that the low fat diet recommendation was a mistake — that it’s not how much fat you eat, but what kind of fat. Vegetable oils, and particularly monounsaturated oils like olive oil have a salutary effect on blood lipid profile, and yes, fat in the diet is satiating. So trying to eat a low fat diet may have actually meant higher calorie intake for some people, also it was an excuse to eat high glycemic index foods (simple carbs, basically) which increases risk for diabetes. So he’s kind of half right but then he goes overboard by recommending saturated fat, which appears to be a bad idea.

    That said, it is indeed difficult to sort out the effects of diet on health, because we are mostly dependent on epidemiological studies and everything is all mixed up together. Meaningful experiments are nearly impossible because of the requirement for decades of longitudinality. So, Tuck, “no good controlled prospective studies” is not the same thing as saying “no evidence at all,” but it is saying we have to live with the weaker evidence that is available. So there is indeed some uncertainty here but that’s no excuse to tout implausible ideas for which there is even less evidence. This is the same sleight of hand as filling in gaps in scientific knowledge with whatever God you happen to believe in.

  3. stanmrak says:

    100 years ago, when everyone ate butter, eggs, full-fat milk and lard regularly, heart disease was virtually unheard of. Then Ancel Keys proposed the saturated fat theory of heart disease, and saturated fat intake in America went into significant decline.
    During the sixty-year period from 1910 to 1970, the proportion of animal fat in the American diet declined from 83% to 62%, and butter consumption dropped from eighteen pounds per person per year to just four. Since the 1930′s, dietary cholesterol intake in the U.S. has increased only one percent. If heart disease is a result of dietary saturated fats, one would expect to find a corresponding decrease in the rate of heart disease.
    Instead, the rate of heart disease continued to climb, and is still rising. Today, it causes about 40% of all deaths in the United States. Clearly, the saturated fat theory is rubbish.

  4. DugganSC says:

    On a somewhat related note, I remember running into an article years ago saying that cholesterol was affected by diet in a minority of the population (1 in 5 was the figure I remembered) and that cholesterol levels in most people could only really be affected by medicine, exercise, and heredity. I suspect that this was a confusion (or possibly the then-current interpretation) of the consumption of cholesterol not affecting cholesterol levels versus it simply being unaffected by diet. Could you comment on this? I’ll admit that I’ve been using that line for years to justify eating large amounts of fatty meats and still maintaining a low cholesterol level, but I’m curious as to how supportable it is.

  5. WilliamLawrenceUtridge says:

    Sure stanmrak, because in that 100 years, we haven’t had massive changes in the amount of physical activity we undertake, the deaths due to diseases, overall diet, home cooked versus restaurant-based eating, the type, quality and amount of animal protein we eat, food processing, the way we measure cholesterol, longevity, etc. etc. etc.

    Simplistic anwers are simple, which is a virtue. They’re also usually wrong.

  6. Janet Camp says:

    Cervantes, I think you make the same mistake as Taubes, et al, in that while olive oil is good it, like all fats, must be strictly limited–at least as far as weight management is concerned. If fat is only 15 or 20 per cent of the diet, I’m not sure it matters what the source is, although I’d certainly advocate for olive oil over lard.

    —–

    Dr. Hall: Thank you for taking this on. Hardly a day goes by that I don’t hear some version of the fat “controversy”, especially the arguments of Taubes, a journalist who has no science credentials that I know of. People continue to fight the idea that it is the total calories that matter more than the source of them–assuming one is not living on a candy bar a day. I read Marion Nestle’s blog–foodpolitics.com daily and value her work in nutrition and public health, but it’s amazing how many people read her and then put forth Taubes’ and Price’s (and now Miller’s I suppose) arguments.

    This explains the appearance of myriad coconut oil products at the coop and Whole Foods–where I go for decent produce, not faddish/cultish “natural” stuff.

    ——-

    stanmrack: Please reread the article. You have fallen into every trap that HH works hard to explain. The thing is, Americans eat twice as many calories per day as they did even thirty years ago and I repeat–a calorie is a calorie is a calorie, and too many of them make you fat.

  7. DrRobert says:

    I never know what to believe when I read something written by a nutritionist. Their general misunderstanding is almost malevolent and their ignorance is abundant.

    I can pick up any nutrition book and immediately start pointing out how they are misrepresenting and straight up lying about a number of things. Aspartame and other artificial sweeteners are beaten to death by them. Boy do they love quoting that San Antonio study, which incidentally was a horrible observational study which correlated weight gain with people who use lots of artificial sweeteners. The authors said their findings were most likely due to people being on unhealthy trajectories, and of course not due to artificial sweeteners themselves. (I believe, in my opinion, based on communication with her, that the lead author, has a high possibility of being biased towards implicating artificial sweeteners for something they aren’t responsible for.)

  8. ConspicuousCarl says:

    stanmrak on 06 Dec 2011 at 10:56 am

    100 years ago, when everyone ate butter, eggs, full-fat milk and lard regularly, heart disease was virtually unheard of.

    OK, let’s do the 60-second research which anyone but Stan Mrak can do…

    Heart disease virtually unheard of in 1911?

    http://www.cdc.gov/nchs/data/dvs/lead1900_98.pdf

    11% of deaths back then. That’s a lot less than today’s rate, but certainly something you would have heard about. So Stan is just wrong about that premise.

    Of course, an intelligent person would wonder if people even lived long enough to have heart attacks in 1911…

    http://demog.berkeley.edu/~andrew/1918/figure2.html

    The other 89% of the population would have found it challenging to die of a heart attack at 55 if they already died from infections at 53.

    There was also very little Internet fraud back then. Maybe Stan Mrak can develop a theory on that.

  9. tuck says:

    @cervantes: “That said, it is indeed difficult to sort out the effects of diet on health, because we are mostly dependent on epidemiological studies and everything is all mixed up together. Meaningful experiments are nearly impossible because of the requirement for decades of longitudinality. So, Tuck, “no good controlled prospective studies” is not the same thing as saying “no evidence at all,” but it is saying we have to live with the weaker evidence that is available.”

    Epidmiological evidence is “no evidence at all”. It does not establish cause and effect.

    Or have you forgotten the results of the hormone-replacement therapy trials based on the epidemiology from the Woman’s Health Initiative?

    http://www.nih.gov/news/health/feb2010/nhlbi-15.htm

    Arguably drawing conclusions from epidmiological evidence is worse than “no evidence”, because it makes you think you know something when in fact you don’t.

    And for folks who think replacing saturated fat with seed oils is a good idea, you really ought to look at the link between seed oil consumption and age-related macular degeneration…

  10. Angora Rabbit says:

    In my opinion Dr. Hall has it right, as usual. It could almost be amusing that several posters on this thread fall into the same fallacy as Miller and Taubes, picking on “my favorite factor” to explain the totality of effect, while simultaneously everyone else must be wrong because the other “favorite factors” fail to account for the effect because they see the deficits in others but not themselves.

    The reality is that it is the MULTIPLICITY of factors that have a net influence on outcome. Something that we teach our nutrition students from the get-go, and they have trouble wrapping their heads around till their senior years. I blame the simple-minded thinking method they are accustomed to, where A must go to B and then B goes to C. This is a fine way to start introducing concepts, but a lousy way to understand how the body works, and it isn’t how real-life factors work. It is a complex of interacting and intercommunicating factors that each have a contributory role to create the final outcome. So you are all right, but it is incredibly naive to focus on one factor only and pretend that it is the be-all and end-all. Thoreau got it right – moderation in ALL things.

    30+ yrs ago we told people to reduce their CALORIC intake, reduce their FAT intake, AND EXERCISE. Instead the American public heard reduce fat intake, decided that was enough, and stopped there. So we got one out of the three, and since the late 1960s per capita caloric consumption continued its steady increase while daily energy expenditure continued to decrease. So OF COURSE obesity continued to climb. Not because the recommendations were bad, but because the American populace did not follow them.

    How a cardiothoracic surgeon like Miller can recommend a high fat, low carb diet is beyond me. Either he slept during his nutrition lectures (assuming his med degree even required them, which is still not common) or he wants more patient income for open heart surgery candidates. Sheesh. Harriet, you are being way too kind about this Bozo.

  11. LovleAnjel says:

    All I know is, this guy says bacon is health food. ’nuff said.

  12. Scott says:

    Epidemiology is certainly weaker evidence than controlled trials, but it’s a very long way from “worse than ‘no evidence’” so long as one is careful to respect the boundaries of what it can tell you – which is precisely what HH was pointing out in the passage you originally objected to! The fact that it doesn’t establish cause and effect is an argument for interpreting it cautiously, not grounds for blanket dismissal.

    There’s certainly room for disagreement about how strong the recommendation should be, based on epidemiology alone. But it’s Not Even Wrong to assert that it’s “no evidence at all.”

  13. nybgrus says:

    @carl:

    You beat me to it mate. The moment I read stanmrak’s post I thought of about 10 bajillion things wrong with it. And was about to post the exact same life expectancy data you already did.

    But hey, IIRC, stanmrak is one of those nutrition loons that loves Null, Mercola, and Adams. So what do you expect?

  14. Chris says:

    nybgrus, he also beat me to it. Though I only have an anecdote: my stepmother’s family had a genetic form of hypertension. They very seldom lived to age 50 or so. In the 1950s the first diuretic blood pressure medications came out, and she and her surviving siblings lived to their 80s (one died during 1918 influenza pandemic and another died of hypertension just a couple of years before the medication was available).

  15. dr.cosa says:

    The Mediterranean is actually a very small sample set from what Ancel Key’s discovered when following dietary habits of Greeks on the island of Crete.

    “Mediterranean” is far too broad a term considering the vast difference in diets between Mediterranean nations like France, Italy, Greece, Turkey, Algeria, Malta, Tunisia and Spain.

    In fact, the entire term is a fantasy, concocted by the diet industry in a way wholly unsupported by evidence. They should have called it the “Cretin villagers” diet as a more apt description. It has grown to become a juggernaut of diet recommendations and cherry picking of actual Mediterranean culture’s eating habits.

    Any one who has eaten southern italian food long enough could easily attest to it’s contents of bread, pasta, tomato sauces, cheeses, pastries, cannolis and a host of cured pork products that dont even remotely resemble anything Cretian villagers ate in these studies.

    Lets stop pretending that term has any valid meaning. I think its poor science to ascribe longevity to a diet when lifestyle is part in parcel of the equation. Observing the eating habits of sunny greek islands hardly makes a case on it’s own for why they might live so long. If anything the advice Key’s should have issued was for people to move to warmer sunny regions and stop smoking to improve longevity.

  16. weing says:

    “Arguably drawing conclusions from epidmiological evidence is worse than “no evidence”, because it makes you think you know something when in fact you don’t.

    And for folks who think replacing saturated fat with seed oils is a good idea, you really ought to look at the link between seed oil consumption and age-related macular degeneration…”

    Do you mean the epidemiological evidence? What makes you say it is no evidence at all when it comes to the Mediterranean diet but want us to look at it when it comes to seed oils and macular degeneration?

  17. Roadstergal says:

    It may be petty, but I did laugh at “Cretin villagers.” Those dense bastards…

    But yes, fair point.

  18. ConspicuousCarl says:

    nybgruson 06 Dec 2011 at 2:14 pm
    But hey, IIRC, stanmrak is one of those nutrition loons that loves Null, Mercola, and Adams. So what do you expect?

    I guess I shouldn’t be surprised, but he claims 30 years of research on diseases, aging, and nutrition. It’s kind of sad to see someone spend so much time doing something when they are so bad at it.

  19. Harriet Hall says:

    @dr. cosa,

    I don’t know about Cretans or Cretins, but when we refer to “the Mediterranean diet” we mean:
    Eating primarily plant-based foods, such as fruits and vegetables, whole grains, legumes and nuts
    Replacing butter with healthy fats such as olive oil and canola oil
    Using herbs and spices instead of salt to flavor foods
    Limiting red meat to no more than a few times a month
    Eating fish and poultry at least twice a week
    Drinking red wine in moderation (optional)

    There is plenty of evidence that this diet is associated with cardiovascular and other health benefits – everywhere, not just in Mediterranean countries.

    @DugganSC,

    It’s my understanding that reducing fat and cholesterol in the diet does lower blood cholesterol levels, but the effect is small, usually not large enough to produce a significant lowering of risk unless drugs are added. One could argue that if you take statins you could eat anything, but most cardiologists would consider that unwise. If nothing else, the high calorie content of fats tends to undermine weight loss, which is important for heart health too.

  20. Noadi says:

    There are a lot of factors that make the rates of heart disease misleading. A big one is that many causes of death have dramatically decreased in the last century and we’re living far longer than before. It’s one of the reasons cancer is more prevalent as a cause of death as well. When you dramatically reduce the number of people who die young you see more deaths from diseases that develop later in life like heart disease. You can’t say “people ate more saturated fats back then and had less heart disease” and conclude that fat reduces heart disease when you ignore that most heart disease develops after age 50 and the life expectancy of the time was 50.9 for men and 54.4 for women compared to well over 70 years now.

  21. dovirstrgn says:

    I’m interested in your “naturalistic fallacy” challenge regarding the assertion of higher nutritional content in animal foods produced by animals that are “happy” – free from undue stress and themselves well-fed – and especially pastured livestock.

    Is there any body of literature on this subject? I don’t think it’s particularly contentious to say that healthier animals produce healthier animal foods. In particular, two examples come to mind: higher omega-3 fatty acid concentrations in butterfat from pastured cows, and higher carotenoid content in egg yolks from free-range pastured hens. Am I mistaken in thinking that both of those things are well-established? I don’t have the time or resources just at the moment to look into it, but if I remember I will later.

    Miller’s citations on the issue may be bad, but given my prior understanding on the issue and my admittedly entirely anecdotal personal experiences – grass-fed beef tastes better and pastured hens’ eggs are so carotenoid-rich that the yolks practically glow orange, but both of those things are subjective, I guess – I feel like if there aren’t good citations to be made, that may be a potential deficiency in nutritional science literature, rather than indicative of no phenomenon.

    I do agree about the overall pattern here. It seems like Miller has extrapolated way beyond supportability and arrived at a rather silly, simplistic Dietary Solution To Everything.

  22. tuck says:

    @Scott: “…so long as one is careful to respect the boundaries of what it can tell you…”

    According to the scientific method, correlation tells you nothing but that you have something interesting that you should do further research on. This, of course, would be the difference between “science-based medicine” and “scientific medicine”. It certainly should not be a basis for treating people, as the unfortunate incident with hormone-replacement therapy illustrates. First, do no harm.

    @weing: “Do you mean the epidemiological evidence? What makes you say it is no evidence at all when it comes to the Mediterranean diet but want us to look at it when it comes to seed oils and macular degeneration?”

    The epidemiological evidence has been confirmed in animal studies.

  23. tuck says:

    @Harriet Hall: “There is plenty of evidence that this diet is associated with cardiovascular and other health benefits – everywhere, not just in Mediterranean countries.”

    You should spend some time and look into it. “Plenty” turns out to be a very small number.

  24. weing says:

    “The epidemiological evidence has been confirmed in animal studies.”
    And that is enough for you?

  25. weing says:

    Don’t get me wrong, I prefer fish oils anyway, but why did you reject animal studies of Mediterranean diet?

  26. Angora Rabbit says:

    Could someone from SBM please explain why my post this morning was selected for moderation and never posted? I can’t imagine that I said something to offend – was certainly not the intent! – and would appreciate a response.

    There were no links in it, btw.

  27. Harriet Hall says:

    @tuck,
    “You should spend some time and look into it. “Plenty” turns out to be a very small number.”
    It did. It isn’t.

  28. Harriet Hall says:

    @Angora Rabbit,

    I don’t know why things sometimes disappear into moderation. Sometimes that has happened to comments of mine, too. I’m guessing it’s some kind of programming glitch. I rescued your comment from moderation and it now appears above.

  29. cloudskimmer says:

    What’s worrying me is that Dr. Miller is working at the University of Washington. Does he instruct and is he teaching interns and residents this rubbish as if it were factual? What do his colleagues at the University and in practice think of his ideas? Does Dr. Miller work in a teaching capacity? Can the University do anything about this? Should they? Does he publish actual research, or just popular articles?

  30. Chris says:

    I suspect he is tenured. He has been there for almost forty years:
    http://www.donaldmiller.com/Curicullum_Vitae.pdf

    Fortunately my son has been referred to a much younger doctor at the UW Medicine Regional Heart Center.

  31. WilliamLawrenceUtridge says:

    dovirstrgn, you may be intereted in Harold McGee’s ”On Food and Cooking”. It’s not footnoted, but it is science-based, has a lot of references and a ton of information on food in general. One thing I do recall from it is that animals killed humanely do produce the best-tasting and tenderest meat because of what stress does to the intracellular constituents (notably depleting glucose and ATP).

    I recall reading somewhere that pasture-fed and wild animals tend to be lower in fat and the fat profiles are different from grain-fed cows and the like. Source? Don’t got one, sorry!

  32. DugganSC says:

    @Harriet Hall:
    Thank you for your reply. I tried doing my own research on it via the internet, but all it got me was a list of contradictory indications (even Wikipedia doesn’t agree with itself with a sentence stating that diet has no effect on cholesterol levels preceding one saying that a non-meat diet leads to lower cholesterol levels). So, the effect is there, but it’s very small. That’s informative.

  33. Purenoiz says:

    @WilliamLawrenceUtridge here is a source for the grass fed vs grain fed cows.
    http://www.nutritionj.com/content/9/1/10/table/T1
    “Table 1 reports that grass finished cattle are typically lower in total fat as compared to grain-fed contemporaries. Interestingly, there is no consistent difference in total SFA content between these two feeding regimens. Those SFA’s considered to be more detrimental to serum cholesterol levels, i.e., myristic (C14:0) and palmitic (C16:0), were higher in grain-fed beef as compared to grass-fed contemporaries in 60% of the studies reviewed. Grass finished meat contains elevated concentrations of stearic acid (C18:0), the only saturated fatty acid with a net neutral impact on serum cholesterol. Thus, grass finished beef tends to produce a more favorable SFA composition although little is known of how grass-finished beef would ultimately impact serum cholesterol levels in hyper-cholesterolemic patients as compared to a grain-fed beef.”

  34. Angora Rabbit says:

    Thanks, Dr. Hall, for the rescue. Dear Spouse tells me that my new laptop may be to blame, with the SBM server not recognizing it/me as a past contributor.

    @cloudskimmer: I hear you. It’s sad. The problem is academic freedom, which I will defend to my dying breath. It’s a two-edged sword. The good side is that it allows academicians to research topics with all protections that may have uncomfortable or unwelcome political implications. It is intended to prevent the Big Chill on research topics.

    The downside is Dr. Miller. Sadly, once one is tenured there is not a great deal one can do if there is not out-and-out misconduct. If he had knowledgeable peers, they could educate his views. But, shockingly, UWash does not offer a nutrition major / lacks a nutrition dept (it’s at Wash State). So speaking kindly there may not be a core intellectual group to dissuade his views. Sigh.

  35. Alix Nemo says:

    I’ve been following this blog for well over a year, and for some reason this post has pulled me out of the shadows.

    There is a good handful of research that comes up with conflicting/controversial results that lead me to question if we can say with any conviction what food is right to eat. Research in this area is very rarely done in ways that provide solid, unbiased, well documented, long term, and “all things accounted for” results.

    While the majority of the people promoting diets like this seem to be a full of “woo” that doesn’t mean it’s not possible.
    Recently I saw a study that was very interesting, called “A high-fat, ketogenic diet induces a unique metabolic state in mice” done by Adam R. Kennedy and 11 other people. I’d link you to the full PDF, but then my post may not go through. :/

    Here is a tiny part of the text from the results, to peak your interest:
    “Animals fed ketogenic diet ate the same number of calories
    as animals that were fed either chow or a high-fat diet but
    nevertheless failed to gain weight. Remarkably, animals eating
    ketogenic diet lost a small amount of weight and achieved the
    same weight and body composition as animals that were calorie
    restricted to 66% of usual daily intake. Fat mass, lean
    body mass, levels of leptin, and glucose were the same in
    ketogenic diet-fed and calorie-restricted animals”

    (the high fat diet they refer to is actually a high carb diet as well)

    It seems to me that there is some scientific evidence that points towards the possibility that eating a certain diet can indeed let you eat a larger portion of fat/calories than we think is normal, and have it affect your fat loss positively.

    Heart and arterial health seem to have similar issues.

    I had a little trouble understanding some of the paper(not a scientist) and would love to hear everyone’s thoughts.

  36. Scott says:

    Such a finding would warrant a careful examination, but even at a high level there are two key limitations of such a study, no matter how impeccably performed:

    1. It’s one study. The claim that a third of consumed calories simply “went away” somehow (excreted, or absorbed into metabolism/activity levels, or something) is quite an extraordinary one, and as we all know, extraordinary claims call for extraordinary evidence. Any finding that striking badly needs independent confirmation.

    2. It’s mice. All sorts of things happen in mice that don’t in humans (and vice versa), so while it raises fascinating possibilities it’s still very preliminary and would need to be confirmed in humans (again, one would really want multiple independent confirmations).

    If the necessary additional research is done and confirms the results, wonderful – that would be extremely valuable and useful information. Until then, it’s nowhere near enough to hang real dietary recommendations on.

  37. CC says:

    I ran across this today, in which a low protein diet leads to more feelings of hunger and more snacking (and thus more caloric intake). It doesn’t address fat, but it was interesting and somewhat related. In the sense that it talks about diet.

    What do the doctors here think – is this study well done?

  38. Badly Shaved Monkey says:

    I’ll acknowledge a conflict of interest at the outset here- my Cholesterol and LDL were high and almost completely unresponsive to strict low-fat diet so now I’m on simvastatin and my numbers have come down like a charm. I’m not overweight and I don’t have other big risk factors for cardiovascular disease. 

    It just seems biologically wrong that I can be at elevated risk for cardiovascular disease and not be able to influence that factor by physiological means. It can’t be that I was born simvastatin-deficient. 

    Yet, high Chol and LDL are risk factors for cardiovascular events. I accept this as well-established fact. 

    Is the missing element that these parameters measure a risk but only because there is something else amiss with my (my society’s) diet? 

    In other words would high Chol and LDL be biologically allowable if something else was set right at the same time. So, we have two ways to reduce cardiovascular risk- achieve lower Chol + LDL or live with high Chol + LDL and get something else right.

    In societies with lower cardiovascular disease rates do they all have low blood Chol + LDL? 

    I have read of an “inflammation hypothesis” relating to cardiovascular risks. Under this, it is not the high lipid levels per se that are the problem but that a pro-inflammatory state leads to the dangerous plaques that block our arteries and initiate platelet aggregation.

    I believe two things sit well under this hypothesis. 
    1. Protective effect of certain types of fats, which shift the balance of arachadonic acid derived inflammatory mediators. 
    2. The protective effect of aspirin is explained less by its effect on reducing platelet aggregation and more by its wider and well-known inhibition of the COX inflammatory cascade. 

    Please, beatrin mind that, as a vet, I have very little professional education in this field, my patients don’t get these problems. I come at this as a dangerously ignorant patient. 

    Thoughts? Comments?

    1. Harriet Hall says:

      @Badly Shaved Monkey,
      Some people tolerate abnormal LDL/HDL levels without developing CVD. Current thinking is that this is due to their genetic makeup rather than to anything different about their diets. Inflammation is clearly involved, but there is currently no reason to think any diet is clinically effective in preventing inflammation.

      “It just seems biologically wrong that I can be at elevated risk for cardiovascular disease and not be able to influence that factor by physiological means.”
      It may seem wrong to you, but it is a fact of life. There is no effective way to normalize high blood pressure without medication, either. And if a woman is at 80% risk of breast cancer because of BRCA1 and 2 genes, no lifestyle changes are likely to influence that factor.

  39. Badly Shaved Monkey says:

    But, for instance, I thought one idea behind the inexorable rise in average BP is that we have more salt in our diets than our ‘natural’ ancestors for whom salt was necessary but it was sparsely distributed, so limited in availability.

    So we address the raised BP by pharmaceutical strategies.

    I’m sorry if this is all plain ignorance, it really is not home territory for me and I may be the victim of media distortions.

  40. Badly Shaved Monkey says:

    A corollary of what you have said is that I am genetically programmed to high Chol and raised cardiovascular disease risk. That may be so, but it would be reasonable to ask where is the evolutionary pay-off. Is it that the risks only impose a cost after we are supposed to have bred and left the stage? But I would still want to look for an advantage to exist for this tendency to high blood lipid values in humans that are in the breeding pool or for there to be some other factor that mitigates the risk

  41. Harriet Hall says:

    HBP may be epidemiologically linked to increased salt, but avoiding salt is not a reliable way for an individual to prevent or treat HBP. Not everyone is salt-sensitive, and people with low salt intake can develop HBP for other reasons.

  42. Harriet Hall says:

    @Badly Shaved Monkey,
    “it would be reasonable to ask where is the evolutionary pay-off.”
    Except that not everything we inherit has an evolutionary pay-off. Chance and spandrels account for some of it. http://en.wikipedia.org/wiki/Spandrel_(biology)

  43. Badly Shaved Monkey says:

    I accept that would be a possibility. I’d not come across the term before though I’ve debated the concept at JREF a few times where we talked about features that might be insufficiently disadvantageous to be selected against. 

    However, that leaves us with two competing hypotheses. Do we have the means to choose? Spandrels appear to be controversial whereas it is perfectly conventional to note a character that looks disadvantageous at first glance but which confers an evolutionary benefit that is obvious once it’s been pointed out. 

    Retention of the caecum by humans looks like a bad idea if all you know about is appendicitis, but having recognised it as a site of immune regulation then it looks like an advantage to have kept it. Indeed one might even speculate that appendicitis is a consequence more of dietary patterns that predispose it to developing disease than it is really the ‘fault’ of the organ itself. The same argument is trivially true all over biology. We get diseases that might extract us from the breeding pool through disability or death but the normal function of the organ which is the locus of disease confers a net benefit to our reproductive success. 

  44. Harriet Hall says:

    I don’t think spandrels are controversial. A basic principle of genetics is that chromosome rearrangements retain linkages between genes that are located near each other. One gene is selected for; another comes along for the ride. It is fun to speculate about things like the possible benefits of retaining an appendix, but it is just speculation. I don’t think there is any evidence that the appendix plays a significant part in immune regulation or confers a benefit to humans, and even if it did, that might not be the true explanation for its persistence. Evolutionary arguments may be “just so stories.” There is no way to go back in history and study what actually happened.

  45. Badly Shaved Monkey says:

    All that said, is it fair of me to say that we really have no idea why some people have stubbornly high Chol & LDL that seems to need pharmaceutical intervention?

    1. Harriet Hall says:

      @Badly Shaved Monkey,
      We do have a pretty good idea why some people have high Chol and require pharmaceuticals: genetics. Not just one gene, but a combination of genetic factors. No practical test yet.

  46. Epidemiological evidence is evidence.

    Regarding HRT, epidemiological studies found an association betw HRT and lower heart diease rates.

    Mathematically, this is correct: they were related.

    Something was going on.

    It turns out is was not HRT, but that adoption of HRT use was an indicator, or proxy, for a person who was an adopter of a wide range of healthy habits, such as not smoking, quitting smoking,exercising regularly, taking a daily baby aspirin, and so on.

  47. WilliamLawrenceUtridge says:

    BSM, keep in mind that evolution is about reproductive advantage. If these diseases only kill you after child-bearing age, there’s no reason for evolution to select them out of the gene pool (or, at least not a strong one). Arguably you can say that having a parent for a long time is an evolutionary advantage, but in the past we lived in small kinship groups making parent-child links less important than in-group/out-group links (I have a pet theory that nations, wars and othering all exist due to misfiring of ingroup/outgroup selection).

    Evolution only cares up to the point that you have babies, there’s not really a process to select for longevity or health into old age. There’s not necessarily a reason something can be found within your genes, a neutral mutation in terms of reproduction could turn out to have catastrophic consequences once you pass 40. Huntington’s disease would be a prime example. Removing that sort of mutation from the gene pool would take a long time, if it occurred at all. Though modern times, featuring extended life span, genetics testing and delayed child bearing, might do what “nature” didn’t.

  48. fsvehla says:

    The naturalistic fallacy only applies in an ethical context (something is right, because it is natural).
    It isn’t invoked here in the evo. bio. nutritional arguments of the author.

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