Monday, December 16, 2019

Retrospective #303: Poor Dr. Walter Willett

“The Nutrition Source,” not to be confused with my, “The Nutrition Debate” (heehee), is the Harvard T. H. Chan School of Public Health’s website. With “My Alternate Healthy Eating Index,” I took a poke at their Alternate Healthy Eating Index in 2015 in The Nutrition Debate #229. To be fair, though, because they deign to criticize the USDA’s Dietary Guidelines, as their HSPH’s “Alternate Healthy Eating Index” amply demonstrates, they deserve some notice.
Much of their gravitas was attributable to Dr. Walter Willett, now retired but then Professor of Epidemiology and Nutrition and chairman of the HSPH. Willett was “the principal investigator of the second “Nurses' Health Study,” a compilation of studies regarding the health of older women and their risk factors for major chronic diseases. According to his Wikipedia bio (which he appears to have written), he has published more than 1,000 scientific articles regarding various aspects of diet and disease and is the second most cited author in clinical medicine.”
Staying “King of the Hill” is a rough game. Ancel Keys, despite numerous attempts to dethrone him, stayed King until long after he was smoldering in the grave. In fact, his ghost still casts a ghoulish pale. And Walter Willett has recently managed to do so too, using the same type of rough play as Keys used. A 2013 piece in Forbes, based on a story in Nature, tells how the “Top Science Journal Rebukes Harvard’s Top Nutritionist.” An editorial accompanying the Nature piece was also scathing. Willett’s offense was to say on NPR that an article in JAMA, showing people who were overweight (but not obese) lived longer than those deemed normal weight, was “a pile of rubbish, and no one should waste their time reading it.” He then organized a conference at Harvard expressly to discredit the JAMA piece.
More recently, Nina Teicholz, author of “The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet,” wrote a New York Times op-ed, “The Government's Bad Dietary Advice.” In it she says, “…the primary problem is that nutrition policy has long relied on a very weak kind of science: epidemiological, or “observational” studies in which researchers follow large groups of people over many years. But even the most rigorous epidemiological studies suffer from a fundamental limitation. At best, they can only show an association, not causation.” Target: Dr. Walter Willett.
“Epidemiological studies can be used to suggest hypotheses but not to prove them,” Teicholz said. “Instead of accepting that this evidence was inadequate to give sound advice, strong-willed scientists overstated the significance of their studies.” Then, she zeros in: “Much of the epidemiological data underpinning the government’s dietary advice comes from studies run by Harvard’s school of public health.” Teicholz doesn’t pull punches. She also takes a hit at the Guideline’s advice on salt by citing an “authoritative Institute of Medicine study.” I cite it in #153: “Salt: Friend or Foe.”
Then, Dr. Willett used his quarterly, “Ask the Expert” interview to address the cholesterol issue. (Remember that the 2015 Dietary Guidelines Advisory Committee said, “cholesterol is not considered a nutrient for overconsumption.”) Largely responding to the Teicholz guest op-ed (that he inexplicably calls the NYT “story” or “article”), Willett says,
“The important point is to have the best possible evidence, and we shouldn’t be basing dietary guidance on just guesses or beliefs. In the case of both the egg issue and the total fat issue we were basically starting with virtually no direct evidence. When the evidence did start to come in – and there were different lines of evidence from our studies based on large cohorts and also short term studies investigating metabolic changes – it showed that people who consume more eggs did not have a higher risk of heart disease even after adjusting for any other factors, and that total fat in the diet was not related to heart disease risk or cancer risk.”
Got that? Willett, a closet vegetarian (some suspect vegan) admits that DIETARY CHOLESTEROL and TOTAL FAT are no longer risk factors for heart disease and cancer. Read that again, please!
But the Forbes piece offers the best rebuke of Willett. “Science is complex, and Willett’s message to his fellow scientists appears to be that the public can’t be trusted with this complexity (except, as noted, when it might be something that he thinks is worthy of research); the question, which the public might ask in turn, is whether Willett can be trusted with complexity given his apparent intolerance for it in other scientists.”  Wow! That’s heavy.

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