Good Science, Bad Science
What should be a landmark book, a book I predict will revolutionize the way Americans eat, will be out at the end of the month. It's the product of seven years hard work by a great science journalist -- perhaps the best one out there -- investigative science journalist Gary Taubes.
In July, I quoted Taubes in Splendor In The Wheat Grass, my answer to a question from a hostile sprout fiend and his meat-eating girlfriend. And here's a link to his new book, Good Calories, Bad Calories: Challenging the Conventional Wisdom on Diet, Weight Control and Disease.
Taubes book deal came out of his terrific cover story in New York Times Magazine, "What If It's All Been A Big Fat Lie?", which can be summarized by Taubes' opening paragraph:
If the members of the American medical establishment were to have a collective find-yourself-standing-naked-in-Times-Square-type nightmare, this might be it. They spend 30 years ridiculing Robert Atkins, author of the phenomenally-best-selling ''Dr. Atkins' Diet Revolution'' and ''Dr. Atkins' New Diet Revolution,'' accusing the Manhattan doctor of quackery and fraud, only to discover that the unrepentant Atkins was right all along. Or maybe it's this: they find that their very own dietary recommendations -- eat less fat and more carbohydrates -- are the cause of the rampaging epidemic of obesity in America. Or, just possibly this: they find out both of the above are true.
This past weekend, he had another Times Magazine cover story, "Do We Really Know What Makes Us Healthy?" about how studies are read and misread; the risks of leaping to conclusions based on observational evidence -- versus large, randomized clinical trials (which, for reasons of expense and ethics can't always be performed); how some studies are interpreted to give "the appearance of cause and effect where none exists"; and what this means for our health. You really need to read the whole thing, but here's the upshot:
So how should we respond the next time we’re asked to believe that an association implies a cause and effect, that some medication or some facet of our diet or lifestyle is either killing us or making us healthier? We can fall back on several guiding principles, these skeptical epidemiologists say. One is to assume that the first report of an association is incorrect or meaningless, no matter how big that association might be. After all, it’s the first claim in any scientific endeavor that is most likely to be wrong. Only after that report is made public will the authors have the opportunity to be informed by their peers of all the many ways that they might have simply misinterpreted what they saw. The regrettable reality, of course, is that it’s this first report that is most newsworthy. So be skeptical.If the association appears consistently in study after study, population after population, but is small — in the range of tens of percent — then doubt it. For the individual, such small associations, even if real, will have only minor effects or no effect on overall health or risk of disease. They can have enormous public-health implications, but they’re also small enough to be treated with suspicion until a clinical trial demonstrates their validity.
If the association involves some aspect of human behavior, which is, of course, the case with the great majority of the epidemiology that attracts our attention, then question its validity. If taking a pill, eating a diet or living in proximity to some potentially noxious aspect of the environment is associated with a particular risk of disease, then other factors of socioeconomic status, education, medical care and the whole gamut of healthy-user effects are as well. These will make the association, for all practical purposes, impossible to interpret reliably.
The exception to this rule is unexpected harm, what Avorn calls “bolt from the blue events,” that no one, not the epidemiologists, the subjects or their physicians, could possibly have seen coming — higher rates of vaginal cancer, for example, among the children of women taking the drug DES to prevent miscarriage, or mesothelioma among workers exposed to asbestos. If the subjects are exposing themselves to a particular pill or a vitamin or eating a diet with the goal of promoting health, and, lo and behold, it has no effect or a negative effect — it’s associated with an increased risk of some disorder, rather than a decreased risk — then that’s a bad sign and worthy of our consideration, if not some anxiety. Since healthy-user effects in these cases work toward reducing the association with disease, their failure to do so implies something unexpected is at work.
All of this suggests that the best advice is to keep in mind the law of unintended consequences. The reason clinicians test drugs with randomized trials is to establish whether the hoped-for benefits are real and, if so, whether there are unforeseen side effects that may outweigh the benefits. If the implication of an epidemiologist’s study is that some drug or diet will bring us improved prosperity and health, then wonder about the unforeseen consequences. In these cases, it’s never a bad idea to remain skeptical until somebody spends the time and the money to do a randomized trial and, contrary to much of the history of the endeavor to date, fails to refute it.
Here's an excerpt from an earlier Frontline Interview with Taubes that's an easier read:
Why is it so easy for us to believe that fat is a bad dietary ingredient?The idea is that fat has nine calories per gram, and carbohydrates and protein have four calories per gram, and somehow the theory is that the denser the calories, the more easier it is for us to eat more of them. What happened is in the '50s and '60s, when researchers started fingering fat as a cause of heart disease, the obesity researchers, the obesity community started advocating low-fat diets, which they had never done before. A low-fat diet is by definition a high-carbohydrate diet.
But you had this sort of synchronicity where you had the heart disease people saying, "Give up fat, saturated fat, for heart disease," and the obesity people started saying, "Give up fat because it must be the best diet because fat is the densest calories." They moved from there without ever testing actually either of those hypotheses, so the obesity people start recommending low-fat diets; the heart disease people are recommending low-fat diets. They have actually no idea whether it's going to cure heart disease, and the obesity people have no idea whether these diets even work. But because they believe that it's only the calories that [are] important, obviously if you give up the major source of calories in the diet, you must lose weight.
You get this hypothesis that animal fats are the worst kind of fats. That seems reasonable.
That came out of studies where you compare the fat consumption in various countries versus the heart disease rates. Basically that's what we still believe, that the Japanese have a very low fat consumption. Greeks have very low animal fat consumption. They have low heart disease rates. The U.S., Sweden, Finland have high fat consumption, they have high heart disease rates, and that's the genesis of that whole belief. "It's a worthless exercise," is what one researcher in the '50s called it. You cannot say that because fat consumption associates with heart disease, that that means it causes heart disease, because a lot of other things, for instance, associate with fat consumption. Wealthy nations have a lot of fat. They eat a lot of fat; they eat a lot of sugar; they get less exercise; they smoke more cigarettes; they drive more cars; they have more televisions.
There's a world of difference between the countries that eat low-fat diets and the countries that eat high-fat diets. And to finger fat because that's what you have in your mind to go in [to the study], is just bad science. But that's what they did, and that's how animal fat came out of it. We knew that animal fat, saturated fat, raised cholesterol, LDL cholesterol, the bad cholesterol, and it was just this sort of series of suppositions--
And we knew that cholesterol was associated--
And we knew that cholesterol was associated with heart disease. The higher the cholesterol, the higher the heart-disease risk. Although when you actually look at the studies, [it's] kind of amazing. If you or I were to reduce our cholesterol levels by 30 milligrams per deciliter, we would probably increase our chances of living an extra 2 years by one-thousandth of a percent or something. For the actual individual who doesn't have extremely high cholesterol, lowering cholesterol makes very little difference in how long you're going to live.
There were several studies done in the late '80s, where they actually calculated how much longer you would live if you cut back on saturated fat. If everyone in the country cut back on saturated fat to that recommended by the government, and cut back their total fat consumption, you could then calculate from these studies how much longer you would live. And the answer was a days to a few months. And as the authors of this study pointed out, that was published in the Journal of the American Medical Association, those are at the end of your life. It's not like you get an extra month between 46 and 47. It's, you're in the nursing home and you die at, say, 77 and three weeks instead of 77 and one week. One commentary that was published along with one of these results said this is the equivalent of rearranging the [deck] chairs on the Titanic.
A while back, I ran into an interesting site about 'The Cholesterol Myth' by Dr Uffe Ravnskov. According to the recent work by Taubes, it looks like Ravnskov is right on!
Bill Henry at September 20, 2007 3:00 AM
Well, if this book gets published, let's see how the scientific community responds. I predict it will be found so full of holes, it will resemble tofu-based Swiss cheese.
Patrick at September 20, 2007 3:10 AM
...in the mean time I'll take my chances and keep eating what makes me happy, which is usually a good mix of fruit/veggies/meats/cheese/carbs. Can't go wrong if you stick to a middle-of-the-road approach.
Gretchen at September 20, 2007 6:45 AM
The cholesterol nazis do seem to have a death-grip on the USA. Used to be the target was 240 total cholesterol. Then they lowered it to 200. Now they've abolished the target altogether and simply recommend reducing to the max. AMA now officially states that the entire population should be taking statin drugs -- pills that have well-known adverse effects on many people, and that make Big Pharma unbelievably rich. There'll always be an America....
Stu "El Inglés" Harris at September 20, 2007 7:55 AM
See? This is why I don't go to doctors. They just want to tell me everything that's wrong with me and get me to buy pills.
I'll know something's wrong when I'm dead.
brian at September 20, 2007 2:24 PM
You must be new 'round here, buckaroo.
deja pseu at September 20, 2007 7:05 PM
Deja is quite right. The shitbag's comment - advertising his product, directly above Deja's comment - will be removed. Here's my e-mail to "Greg" -- GarMonavie@aol.com, in case you want to tell him what you think of people who try to steal advertising space for their products on the site I pay for, and work very hard on, while pretending to comment on an entry. What a tiny little turd of a man. Here's the e-mail I sent him:
SUBJECT: invoice, $100, advertising on advicegoddess.com
Amy Alkon at September 20, 2007 7:22 PM
Want to see science? Here's science:
http://scienceblogs.com/insolence/
I'll see if it would amuse Orac to take apart that garble.
Amy Alkon at September 20, 2007 7:25 PM
Naturally, the asshat made (complimentary) mention of Nicholas Perricone -- which I know all about, no, not because I'm one of the sheeple spending big bucks on Perricone products, but because I've read all about him on QUACKWATCH.com:
http://www.quackwatch.org/11Ind/perricone.html
Amy Alkon at September 20, 2007 7:35 PM
The cholesterol nazis do seem to have a death-grip on the USA. Used to be the target was 240 total cholesterol. Then they lowered it to 200. Now they've abolished the target altogether and simply recommend reducing to the max. AMA now officially states that the entire population should be taking statin drugs...
The same thing is being done with diabetes; now there's a relatively new "pre-diabetes" numbers range. I always double-check the recommended U.S. ranges against those from other countries' medical organizations, which I assume are less influenced by the pharmaceutical industry.
What also seems to work well--at least for me--is to eat the bigger, fattier meals earlier in the day--when the body metabolizes calories more efficiently--and the lighter meals later.
Doobie at September 20, 2007 8:57 PM
Actually, Doobie, I believe this is a myth. Here's a link:
http://news.bbc.co.uk/2/hi/health/3263249.stm
Amy Alkon at September 21, 2007 3:59 AM
Don't get me started about Perricone. A few years back they pushed some free samples on me at one of the Norstrom's makeup counters. I tried it (hey, it was free) and it made my face break out horribly. And I'm not someone who is prone to breakouts. Took two weeks for my skin to clear up.
deja pseu at September 21, 2007 5:50 AM
"pre-diabetes".... yes, I'm familiar with that one, too. Last year a cardiologist told me disapprovingly that I was pre-diabetic. I didn't react but I thought "Yeah, I'm pre-wealthy, too".
Stu "El Inglés" Harris at September 21, 2007 7:34 AM
I love that. Pre-wealthy. Yes, me, too.
Amy Alkon at September 21, 2007 8:01 AM
I've pretty much had it with my doctor too. All she's done for years is try to push prescriptions down my throat, none of which I've taken. I only needed her to get my prescription for my birth control pill, and I quit taking those 4 years ago. I hindsight, I could have gotten those from the hassle free clinic, thus removing the hassle from my life.
I really don't need the fear-mongering they use to try to get you sucked into the big money system of pharma drugs and expensive procedures that you really don't need. Since everything is paid for by the government up here, their only angle is figuring out how to use you to get money from the system.
Chrissy at September 21, 2007 9:13 AM
You're a Canuck?
Amy Alkon at September 21, 2007 9:24 AM
The state of nutrition science today, not just in the U.S. but over the entire world, is absolutely pathetic. There is no longer very much actual science there. They've degenerated to the pseudo-science level of horoscopes and tarot-card reading. There are far too many researchers out there measuring noise, with poorly controlled studies, and claiming breakthough results based on correlations below the significance threshold. The same is true in cancer research. Anyone wonder why there's been so little real progress in cancer treatments over the past 40 or so years? It's because research money goes to the researchers who get the most headlines, not to the researchers who do the most worthwhile work.
If I were head of the NSF, I would impose an across-the-board moratorium on epistomological studies. You want a grant to see if vitamin C successfully treats colds? Fine, then devise a method of tracing the metabolism of vitamin C through the body and the direct effects, if any, that its metabolites have on rhinoviruses. Don't go out and give 1,000 people vitamin C doses, with no other controls, and then pretend that you've accomplished something.
Cousin Dave at September 21, 2007 12:46 PM
Yup, I'm one of those polite boring people that live north of the border.
If you can imagine a health care system where anything and everything will be paid for as long as a doctor can come up with a reasonable excuse, welcome to my world. I have been very sceptical of anything recommended by any doctor for the last 20 years, and am consequently in perfect health. I can see where they are coming from, as they are under a lot of pressure, and they can still be sued for malpractice, so the motivating factor behind any of their decisions is 'rather safe than sorry'. Unfortunately for the patient, safe for the doctor means lots of prescription drugs and surgery for the patient.
Chrissy at September 24, 2007 11:47 AM
I come from a Family of 11 and my folks never had Med. Ins. My Father and Mother distrusted the AMA and only dire circumstance were we ever subject to there services. We ate well, right out of the garden. Pop or Ice cream was a monthly treat. None of us are lard asses like the majority I see every day. Maintained my per college weight till 55 then progressed to 200. Must have been the 6-10 beers I drank every day cense HS catching up to me. I've been on the Atkins diet for two years and will be the rest of my life. It took less than 3 months to get back down to 175 and it's easy to maintain. (That’s achieved with very little exercise and changing beer to lower carb content). I have never been to a doctor for anything other than accident repairs.
If I’m permitted to give my advice here it would be to stay away from the AMA drug pushing medical establishment if at all possible.
Bill K at September 26, 2007 11:40 AM
Great interview! I realised that the work in Taubes. This book gives good information about the this.
Jesmi at October 5, 2007 10:06 PM
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