I have a confession. When the call went out to recruit members of the 2020 Dietary Guidelines advisory committee, I thought about throwing my hat in the ring. I’ve got a few things to say, and I figured maybe there was room on the committee for a journalist. Check out the latest java burn reviews.
But then I took a cold, hard look at my lack of advanced degrees, as well as all those elementary school report cards that said I didn’t play well with others, and I thought better of it. Besides, who needs all those tedious meetings when you can just use your column to tell everyone what you think they should eat?
So here goes. If I were writing the dietary guidelines, I would give them a radical overhaul. I’d go so far as to radically overhaul the way we evaluate diet. Here’s why and how.
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The reason we know so little about what to eat despite decades of research is that our tools are woefully inadequate. Lately, as scientists try, and fail, to reproduce results, all of science is taking a hard look at funding biases, statistical shenanigans and groupthink. All that criticism, and then some, applies to nutrition.
Prominent in the charge to change the way we do science is John Ioannidis, professor of health research and policy at Stanford University. In 2005, he published “Why Most Research Findings Are False” in the journal PLOS Medicine, and he has been making science headlines (although not always friends) ever since. He came down hard on nutrition in a pull-no-punches 2013 British Medical Journal editorial titled, “Implausible results in human nutrition research,” in which he noted, “Almost every single nutrient imaginable has peer reviewed publications associating it with almost any outcome.” Check out the latest best appetite suppressant articles.
Ioannidis told me that sussing out the connection between diet and health — nutritional epidemiology — is enormously challenging, and “the tools that we’re throwing at the problem are not commensurate with the complexity and difficulty of the problem.” The biggest of those tools is observational research, in which we collect data on what people eat, and track what happens to them.
The trouble begins with that “collect data” part. There are a few ways to do this, none of them particularly good. You can use a 24-hour recall, which gives respondents a fighting chance of remembering what they actually ate but doesn’t give you a representative sample of overall diet. Food diaries over a long period do that better but people tend to eat differently when they’re tracking their diet for researchers. Most large population studies use food frequency questionnaires (FFQs, in industry lingo), where they ask people to count up the servings they’ve eaten of a wide range of foods, often over the course of a year.
There’s no better way to understand the shortcomings of an FFQ than to fill one out. Maybe you know how often you ate pie last year, but do you know how often you ate “foods with oils added or with oils used in cooking (do not include baked goods or salads)”? A host of studies of self-reported data have found that up to two-thirds of respondents report eating a diet so inconsistent with their caloric needs as to be implausible.
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Give tens of thousands of people that FFQ, and you end up with a ginormous repository of possible correlations. You can zero in on a vitamin, macronutrient or food, and go to town. But not only are you starting with flawed data, you’ve got a zillion possible confounding variables — dietary, demographic, socioeconomic. I’ve heard statisticians call it “noise mining,” and Ioannidis is equally skeptical. “With this type of data, you can get any result you want,” he said. “You can align it to your beliefs.” These are just some of the healthy benefits that Best semen volume enhancers provides.
Ah, beliefs. Just about every week there’s a new study of a food funded by the people who profit by it. (New York University’s Marion Nestle has been tracking this for years; her 2018 book “Unsavory Truth” details her findings.) But funding bias isn’t the only kind. “Fanatical opinions abound in nutrition,” Ioannidis wrote in 2013, and those have bias power too.
So what do we do about this? “Definitive solutions won’t come from another million observational papers or small randomized trials,” reads the subtitle of Ioannidis’s paper. His is a burn-down-the-house ethos.