Monday, February 11, 2008

And the Answer is...

Steven H. Woolf, MD, MPH, from Virginia Commonwealth University and Marion Nestle, PhD, MPH, of New York University:

"When the prevailing message fails to achieve its intended aims or achieves the wrong ends, the solution is not to abandon the enterprise but to reshape the message to achieve desired outcomes."

Do Dietary Guidelines Explain the Obesity Epidemic?

13 comments:

  1. Oh, man, don't get me started.

    Did you see Nestle's blog? I commented on this there.

    Dr. Nestle does have many good things to say regarding the marketing of food to children and the importance of whole foods for a healthy diet. However, I believe her mantra ("Eat less, move more") is at best useless and quite likely harmful.

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  2. Wow. I'll have to write a more extensive blog on this when I get some time. A few comments for the moment:

    I'll have to look up how they define "evidence based". There is a truly rigorous mathematical basis for weighing the evidential support of hypotheses - the problem is that almost nobody uses it. The reasons for this state are historical and sociological, but the end result is the current situation, where we're supposed to choose from "lies, damned lies, and statistics". If this is the case for the referenced analyses, then the supposed "analytical rigor" is built on a mathematical house of cards.

    That a lot of papers, pages, etc. show support for a particular hypothesis does NOT imply that hypothesis is "true". Another hypothesis might have greater significance based on the evidence, but you can't know that unless you ask the question. I would bet that the quoted evidence on the benefits of a low-fat/low-calorie diet (e.g. Ornish) are equally (if not better) explained by the carbohydrate hypothesis, because the combination of calorie restriction and increased intake of fruits/vegetables almost certainly represents a drastic decrease in glycemic load and insulin response. But if you don't specifically compare that hypothesis to the fat hypothesis, you can't possibly know which is better supported by the evidence. The carbohydrate hypothesis has the added support of information from molecular and cellular biology, which seems to be routinely ignored for the purposes of devising dietary guidelines.

    The referenced "1400 pages [of] meticulous analyses of the scientific evidence" are meaningless unless you consider ALL of the evidence. Further, when looking at results of many different studies/publications, one needs to assess how much added weight they give to a hypothesis. If Paper B simply parrots Paper A, nothing is added. But publication counts are frequently used as an argument for the "truth" of a hypothesis.

    Finally, the authors blur the line between providing information and making recommendations. When a government or other scientific agency provides information, it's just saying "here's what we know", and it is up to the individual to make behavioral decisions. Recommendations imply that the decision of what is best has already been made. Thus consumers don't have to decide - the government has already decided the optimal behavior. This is generally accompanied by a paucity of actual information - which makes sense, as the decision has already been made for you. If you have no decision to make, then why would you need any information? We then are faced with situations where we have no choices, such as with school lunches. The organization that supplies lunches for my son's school is quite proud of how it follows the food pyramid. But it also offers no alternatives. That's fine for me, since I can make him a lunch that I feel reflects my information about what is healthiest. But for most parents, the overwhelming alignment of government, school, lunch providers implies overwhelming evidence that they're all recommending the right thing. But only the government has bothered to examine any evidence at all, and a subset at that. Everyone else is just parroting the "recommendations."

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  3. Did you see that study by Tufts that said:

    "...Americans are at risk of having excessive energy intake even if they follow the 2005 FGP food serving recommendations. "

    http://jn.nutrition.org/cgi/content/full/136/5/1341

    I'm sorry if you already blogged on it, but I couldn't find a search through your past entries.

    enjoy anyway!

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  4. Anonymous9:45 AM

    That makes sense, Drs Woolf and Nestle: just keep pounding that square peg into the round hole....

    The current state of PC no-animal products recommendations reminds me of a battered, splintered peg...boy, they pounded the sh!t out of that sucker...but they got it in! See, Mom, it fits!!!

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  5. Anonymous10:35 AM

    This seems to be another article written by people with tunnel vision. They tend to blast anything that goes against the perceived norm. Then as a fallk back they always invoke the poor and helpless cards. They just can't bring themselves to admit that high carb intake (part of which is added sugar to many products)is the problem. Like Ancel Keyes did, they ignore any data that doesn't fit their hypothosis.

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  6. calianna12:57 PM

    "When the prevailing message fails to achieve its intended aims or achieves the wrong ends, the solution is not to abandon the enterprise but to reshape the message to achieve desired outcomes."

    Don't mind me, I probably just read it too fast to notice it, but I didn't find this exact quote in the linked article. However, if they said this, they are indeed leaving themselves open to ever so slowly changing the message by their careful choice of the words "Reshape the message to achieve desired outcomes".

    As Nonegiven said on the posting about the question: "Obviously it must be to scream it louder and louder while making incremental changes in the message that move it (glacially) in the direction of the truth while blaming anything and everything else for any failures."

    As they make these incremental changes (reshape the message), and ever so slowly move the message in the direction of truth, they will eventually - once it has moved far enough to the direction of truth - actually begin to see the desired outcomes of normalized weights, and better health.

    I doubt it will ever reach the side of truth in our lifetime... or at least not in my lifetime. There's just too much money at stake for everyone involved in promoting the eat less, move more, low fat, low calorie propaganda to just do a sudden 180. This is a change that will most likely take at least 20 years, if not 50.


    ~~~~~

    Which reminds me of the plethora of packages of 100-calorie packs for literally dozens of "food" items I noticed at Costco this morning. I don't know whether these things are all over the store in regular grocery stores or not, because I don't usually go down those aisles, but all the various types of snack items were together at Costco, stack after stack of big boxes of 100 calorie snack packs of cookies, chips, candies, even cereals.

    Never mind that the vast majority of those products were nothing more than artificially flavored sugar and starch. Nutritionally speaking, they're nothing more than a bag of empty carb calories, with a few poor quality vitamins coming from a witch's brew of chemicals. And yet these are considered a "healthy snack choice", simply because they only have 100 calories.

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  7. Don't mind me, I probably just read it too fast to notice it, but I didn't find this exact quote in the linked article.

    Second to last paragraph in the PDF.

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  8. *sigh*

    I really, really don't get it. Is it so difficult to see that since the dietary recommendations changed, we've been fat and sick?

    Posted a comment on Nestle's blog, and in mine for posterity :) Thanks for posting this!

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  9. "Which reminds me of the plethora of packages of 100-calorie packs for literally dozens of "food" items I noticed at Costco this morning."

    Mark Sisson of Mark's Daily Apple said it best. 100 calories of junk is still junk.

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  10. calianna6:50 PM

    Second to last paragraph in the PDF.

    Thanks Regina - I see it now. :)

    Mark Sisson of Mark's Daily Apple said it best. 100 calories of junk is still junk.

    Yes, it is.

    But just try convincing the fat phobic public that something is not good for them when it's low fat/fat free and only 100 calories.

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  11. Unfortunately they are correct in evoking the post hoc ergo propter hoc fallacy

    The fallacy of inferring causality
    from a temporal association is familiar to methodologists, but the suggestion of causality in this case is also naive on policy grounds, because it assumes that a guideline could singlehandedly change a nation’s eating habits.


    But the irony of of it all, is they fail to see that a similar fallacy, Cum hoc ergo propter hoc is responsible for what evidence there is against fat.

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  12. calianna8:05 AM

    it assumes that a guideline could singlehandedly change a nation’s eating habits

    In other words:

    "Don't blame us, we just come up with these silly things, we had no idea that anyone would actually listen to them, haha!"

    Are they setting themselves up to pass the buck - again?!

    So let me get this straight:

    It's your fault if you can't follow our guidelines because you're starving and exhausted from following them. It's your fault, because you're obviously doing something wrong. (I could insert a comment about the thing we did wrong was to follow the guidelines to begin with, but I'll refrain. Oops, did I just say it anyway?)

    But if you follow our guidelines and get fat and diabetic, it's still not our fault, because we didn't really think you'd follow them.

    Amazing. Just amazing.

    They come out with these guidelines - a pronouncement nearly tantamount to royal decree, since it comes from a gov't agency that's supposed to have our best interests at heart. Then they keep pushing it until they get all the nutritionists and doctors on board. The doctors and nutritionists, in turn start hammering their patients and clients with the guidelines.

    Then over the course of a few years everyone from journalists to food processors jumps on board (having been so severely warned about their own diets, by their personal doctors and nutritionists), touting the virtues of cholesterol free low fat this and 100 calorie that - based on information that they got from these very guidelines.

    And they don't think the guidelines could possibly be responsible for changing the nation's eating habits?!


    I've got news for them - it's not just the US that's been affected by their guidelines, it's England, Australia, and all other developed countries that are being fed the fat phobic propaganda too. What's happening in this country, and is starting to happen in other developed countries is only the tip of the iceberg.

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  13. And they don't think the guidelines could possibly be responsible for changing the nation's eating habits?!

    Yeah, people were really following the guidelines. Thats why McDonalds revenue tripled during the same time frame. Not to mention super sizing, stuffed crust pizzas, doubling of restaurant portions, and more people eating out more often. Yeah, it was those guidelines.

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