High-fructose corn syrup and scientific research: an exchange
Photo: Princeton University, Office of Communications, Denise ApplewhiteI have to admit I was a bit puzzled (and also flattered) by author James McWilliams’ article on the Atlantic website that focused on how food writers in general (and me in particular) “got the science wrong” on high-fructose corn syrup (HFCS). At issue is the question of whether we at Grist hype bad science on HFCS because we have previously decided that HFCS carries health risks over and above its caloric content. McWilliams claims that we ignore older studies that don’t support this conclusion in favor of newer science that does.
Exhibit A for McWilliams was a post about a fructose study that I wrote almost a year ago, which was based on a news article that turned out to be riddled with errors. While it’s true we did initially repeat the errors, we also quickly went back and fixed them. Indeed, anyone following the link McWilliams offers will read not only the corrected piece — but a full disclosure about what happened along with a nice discussion in the comments including contributions by the lead author of the study in question.
Rather than reading my mistake as a general failure to understand and report on scientific research, I think of it as, well, a mistake — which I quickly and openly corrected. Mistakes happen. Indeed, despite the blaring headline about “getting the science wrong,” the issue McWilliams is addressing is more accurately described as disputes among scientists.
Take for example, the now infamous Princeton study which I wrote about last March that indicated differences in how HFCS is metabolized in the body vs. cane sugar. As epidemiologist Kelly Brownell, one of the nation’s top experts on obesity and director of Yale’s prestigious Rudd Center on Food Policy and Obesity, recently acknowledged, the Princeton study’s results were indeed “pretty concerning.” Obviously, this particular study is by no means the final word, but a careful review will show that the study does provide solid and compelling evidence for his conclusions.
Tellingly, the very 2008 study McWilliams points to in order to establish the settled nature of the science on HFCS, in its abstract says that “this review highlights the fact that limited data are available about the metabolic effects of HFCS compared with other caloric sweeteners.” The Princeton study was specifically designed to fill in these scientific blanks.
It would be a shame, though a sadly familiar one, to reject a study’s conclusions merely because it contradicts earlier science.
Even McWilliams observes, “Critics are still unpacking the Princeton study.” That’s true, but then he adds this: ” … so it would be unfair to say that it’s been completely debunked.” I find the use of the word “debunked” curious. Myths, half-truths, and deceptive marketing practices should get debunked. But is that the approach to take with rigorous science by well-regarded researchers from one of the nation’s top universities? How about “corroborated”? Or “replicated”? Or just “examined”? It almost seems as if McWilliams thinks it’s his job to debunk science that overturns the status quo. In doing so, he — wittingly or not — aligns himself with the industry flacks who run around trying to undercut science that might threaten corporate profits.
So, yes, I do believe it’s possible, even necessary, to highlight the potential risks of HFCS consumption if the science supports it. It’s also important to acknowledge that science progresses — new work can indeed overturn currently held assumptions. As to the Princeton study, I did an extensive Q&A last spring with Dr. Bart Hoebel, its lead author. In the interview, Hoebel addresses many of the specific methodological criticisms leveled by nutritionists at his work — with the clear suggestion that critics were not fully engaging with the science behind the study, but rather were indulging in knee-jerk reactions. See for yourself.
I think it’s also worth referencing a follow-up post I wrote back in April about the HFCS controversy. The points I made there are as relevant as ever:
I understand and accept that a healthy skepticism is necessary in scientific debate. But reading the responses from “independent” voices (i.e. people not affiliated with Big Food or King Corn), it’s hard not to feel that some of this skepticism is far from healthy.
Some of it, I fear, involves many critics having bought in to generalized industry demands of absolute certainty when evaluating the risks presented by industrial chemicals and additives (though derived from corn and defined as “natural” by our government, high fructose corn syrup is nothing if not an industrial product). We allow corporations to wield this requirement of absolute certainty as a shield against any reasonable use of regulators’ “precautionary principle,” i.e. the point where the need for government regulation to protect individuals or the environment trumps corporate interests.
…One way to look at the effect of something like HFCS is at the individual level — how does it affect your health to consume it? What additional risk (or not) of disease or early death does it confer on you? For many, that difference compared to table sugar is relatively small and thus is deemed irrelevant — perhaps even dangerous to discuss. Cut way back on all sweeteners and you’re better off, goes the logic, so what’s the point in fighting over which sweetener is worse. This, as I’ve mentioned in previous posts, is a large part of the objection many have to continued research into the health effects of HFCS.
But it’s also important to look at population-level effects. The increase in an individual’s health risks in consuming HFCS rather than table sugar may indeed be small, but when you scale it up to a nation of 300 million people (much less billions of people worldwide), those small individual increases in risk may add up to tens, if not hundreds, of thousands of cases of diabetes and heart disease and billions of dollars in additional health costs to society. And while there may be some cases where HFCS severely and acutely affects an individual’s health, these longer term population-level effects of HFCS shouldn’t be ignored and don’t make the Princeton study results any less valid —
but I suspect that, to many analysts, they are and it does.
I’d add one more thing — why exactly does HFCS need any defenders? I mean, why shouldn’t the bar to ban it be incredibly low? It was introduced on a mass scale 1) as a means to soak up excess corn — corn that humans couldn’t eat unprocessed — and 2) as an unintended consequence of the continued existence of a powerful sugar cartel. ADM — the company that probably profits most from HFCS and is definitely not in the sugar business — has become one of the top supporters of continued sugar quotas and tariffs since they have kept sugar prices high and thus kept HFCS competitive.
HFCS is the love-child of misguided protectionist trade polices along with misguided agricultural policies and by no means does it represent real “innovation.” In my view, even the hint of health issues should be enough to invoke the precautionary principle. But not in the US, where if something sickens us (or even kills us) slowly enough, companies get to market it, profit from it and — if and when it ever does get banned — receive full immunity from future lawsuits.
As the totality of my work clearly demonstrates, I don’t think that HFCS caused the obesity epidemic. I have written about the broad and complex causes of obesity. And the need to radically reduce our consumption of all sweeteners as well as processed food in general (and referenced the risks of attacking individual nutrients as “bad”). My work on HFCS is a small fraction of the writing I’ve done on what it will take to address obesity in this country. And yes, it is true that only the Corn Refiners Association could make U.S. Sugar — oligarchs at least as bad as King Corn, but with the good sense to keep a low profile — look good. But really, is that a reason to look the other way?
There is something in McWilliams’ article with which I can wholeheartedly agree:
We need to therefore build on the pioneering work of Michael Pollan to show how corn subsidies have depressed the true cost of corn by almost 30 percent over the past decade or so. We need to show how this has led to the proliferation of cheap junk food, not to mention billions in profits for big food producers. We need to show how these subsidies have created the obesity epidemic. And we need to show how it’s the artificially low price of HFCS, rather than HFCS itself, that’s the ultimate outrage when it comes to the inequities of food and its impact on human health.
The good news is that Tom Philpott, myself, and others here at Grist have been doing exactly that for the last several years. (See our work on food, agriculture, ag policy, ag subsides, obesity, corn, HFCS, health.) I like to think McWilliams shares the goal of reforming an unsustainable food system. And I’ll just leave it at that.