Mediterranean Diet Study Has Been Retracted, Health Link No Longer Causative

Discussion in 'Scientific Studies' started by haidut, Jun 25, 2018.

  1. haidut

    haidut Member

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    By now, there is probably no adult in the Western world who has not heard of the Mediterranean diet and all of its supposed benefits for health. While the buzz about the diet has been going on for decades, a massive study was published in 2013, which pretty much legitimized the health claims made by nutritionists and dieticians in regards to the diet.
    https://www.nejm.org/doi/full/10.1056/NEJMoa1200303

    Well, that study above was retracted last week due to poor study design. The poor design included lack of proper randomization and in some cases massive assumptions about study participants that were presented as solid facts. As a result, the study has been re-analyzed and about to be republished. The new study will still claim that there is a positive link between the diet and good health outcomes. But the link will no longer be claimed to be causative. I personally suspect that the health benefits are due to the way of life of the communities in that part of the world and not so much in the diet. When the diet was tried as an intervention in a few clinicals trials in US and some Asian countries, it did not result in any improvement in the measured biomarkers. Maybe it is because the olive oil used in the intervention trials is nothing like the "real deal" used in Mediterranean countries. I know @Such_Saturation feels pretty strongly about that having tries both the local Italian olive oil and the commercial varieties sold around the world :):

    The most important study of the Mediterranean diet has been retracted

    "...In 2013, the New England Journal of Medicine published a landmark study that found that people put on a Mediterranean diet had a 30% lower chance of heart attack, stroke, or death from cardiovascular disease than people on a low-fat diet. It received massive media and public attention when released, and since has been cited by 3,268 other scientific papers. The study had tremendous impact on the field of nutrition and health science. Yesterday (June 13), however, the journal retracted the study—providing a new reason for skepticism about how effective the now-popular Mediterranean diet really is. The reasons for the withdrawal are complicated, having to do with the methodology of the study. As Alison McCook of the Retraction Watch blog writes for NPR, this retraction is the result of the work of John Carlisle, a British anesthesiologist and self-taught statistician. Carlisle has spent recent years analyzing over 5,000 published randomized controlled trials (the gold standard of medical science research) to see how likely they were to have actually been properly randomized. In 2017, he reported his results: at least 2% of the studies were problematic."

    "...As Cook reports, the lead author of the paper, Miguel Ángel Martínez González, saw Carlisle’s analysis and decided to follow up with a thorough review of the study design. The study was supposed to randomly assign participants to either the Mediterranean diet with a minimum of four extra tablespoons of olive oil a day, the same diet but with at least an ounce of mixed nuts, or a low-fat diet. But Martínez González found that of the approximately 7,500 participants in the study, 14% had not actually been randomly assigned. Instead, many married couples were assigned to the same group. In one particularly troubling case, a field researcher decided to assign an entire village to a single group, because some residents were complaining that their neighbors were getting free olive oil. The field researcher working never reported the decision. Martínez González and his team spent a year reanalyzing the data, working with outside experts. The end result is that the study’s overall findings are still accurate in one sense: There is a correlation between the Mediterranean diet and better health outcomes. But in another sense, the paper was entirely wrong: the Mediterranean diet does not cause better health outcomes. That might seem like a minor difference, but in the world of medical science, it’s incredibly significant, and the change robs the study of much of its original power."
     
  2. lollipop

    lollipop Guest

  3. OP
    haidut

    haidut Member

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    Ha, well if it has a decent amount of red meat then it is not quite "Mediterranean", is it? Nothing against the Mediterranean diet, I just think it has become another marketing tool, with very little meaning and impossible to reliably define.
     
  4. Spokey

    Spokey Member

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    The premise of the Mediterranean diet being low red meat always bothered me, after all I associate Italian cooking with bolognese sauce, lasagna, osso bucu, and then elsewhere in the med they're scarfing down lamb shanks and cheese. It reminds me of the notion spread around that the traditional southern Japanese diets were vegan, which I suppose is true if you ignore all the pork and fish they slammed down, a lot of it stewed in sugar that everyone is so terrified of (and they produce locally).
     
  5. OP
    haidut

    haidut Member

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    True, I am not sure who started the whole rumor of Mediterranean diet being low in red meat but that is its current definition in Western medicine. Come to think of it, Portugal, France, Spain, and of course Italy (but especially the first 3) are very heavy meat-consuming regions, with pork, game, poultry, beef and lamb (more in the Greece/Turkey region) being cornerstones of the local diet. Dairy too.
    Maybe the study should be renamed "Faux Mediterranean not linked to improved health".
     
  6. lollipop

    lollipop Guest

    True. Marketing possibilities abound - lol.
     
  7. burtlancast

    burtlancast Member

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    Well, where does that leave Michel De Lorgeril then ?

    After first being for the cholesterol disease theory, then switching to the mediteranean diet, is he now back to square one ?

    We need to get him asap enough shirts to put back on.
     
  8. yerrag

    yerrag Member

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    Oy vey, there in no Neapolitan ice cream in Naples. Is there a Mediterranean diet in the Mediterranean?
     
  9. lollipop

    lollipop Guest

    Right?!?!
     
  10. thomas00

    thomas00 Member

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  11. Such_Saturation

    Such_Saturation Member

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    I don't know about Spain but here in Italy people change what they eat every month of the year and every 100 miles of territory. Olive oil is prevalent but we are talking about teaspoons a day. The benefit is probably from not having the seed oils instead.
     
  12. dbh25

    dbh25 Member

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    Has the obesity rate there changed?
     
  13. Such_Saturation

    Such_Saturation Member

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    On average for sure. But for example, my grandmother wasn’t exactly thin either. I imagine because of the war famine, but who can say.
     
  14. Sharbysyd

    Sharbysyd Member

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    I'm fairly new to this forum but not new to learning about how to eat and be healthy. These kinds of things frustrate me so much. I feel like it's hard to believe any of the studies. I wish someone would just get the right info out there. I'm hoping that it's Ray Peat. I'm still learning about this way of eating and haven't transitioned yet from low carb, but I'm sold on the PUFA thing so far.
     
  15. nwo2012

    nwo2012 Member

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    Are you a Yid?
     
  16. yerrag

    yerrag Member

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    No, just like the use of that expression.
     
  17. Wichway?

    Wichway? Member

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    I believe this as well after reading about a lot of the blue zones in the world where people are freer from the major diseases which kill Westeners. Low stress lifestyle and jobs, lack of hurry sickness and clock watching, high social connectedness and support, consumption of locally grown produce, and moderate exercise and outdoor lifestyle. All of these things cannot be made up for by vitamin supplements, bouts of aerobic exercise and drugs.
     
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