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What causes obesity?

According to Gary Taubes, writing in the New York Times Sunday Review, we don't really know.

I agree.

Here is Taubes:

Here’s another possibility: The 600,000 articles — along with several tens of thousands of diet books — are the noise generated by a dysfunctional research establishment. Because the nutrition research community has failed to establish reliable, unambiguous knowledge about the environmental triggers of obesity and diabetes, it has opened the door to a diversity of opinions on the subject, of hypotheses about cause, cure and prevention, many of which cannot be refuted by the existing evidence. Everyone has a theory. The evidence doesn’t exist to say unequivocally who’s wrong.

and

One lesson of science, though, is that if the best you can do isn’t good enough to establish reliable knowledge, first acknowledge it — relentless honesty about what can and cannot be extrapolated from data is another core principle of science — and then do more, or do something else. As it is, we have a field of sort-of-science in which hypotheses are treated as facts because they’re too hard or expensive to test, and there are so many hypotheses that what journalists like to call “leading authorities” disagree with one another daily.

If I'm not mistaken, Taubes is leading an effort to raise funds to experimentally test his conjecture  (related to effects of sugars and other carbs) about a cause of obesity.  He has written persuasively about his views, but rather than leaving it at that, he's putting his money where his mouth is, and using scientific experiments to test his theory.  Good for him.



The New Yorker on Atrazine

The New Yorker has a long article appearing online today about the controversy between a Berkeley professor (Tyrone Hayes), his research on the herbicide atrazine, and Syngenta - the company that makes it.  

I found this article disturbing in many respects.  I have do doubt Syngenta faces all kinds of chemophobia fear mongering, and constantly has to fight public battles with strategic activist groups who attempt to alter public opinion and public policy, sometimes based on shaky science.  I wish the New Yorker article would have discussed more of that dynamic.  Nevertheless, what it does reveal are allegations of internal memos from the company with  tactics (most of which were apparently never implemented) to smear and discredit the Berkeley professor.  That ought to frighten any academic working on controversial issues, and it unfortunately is likely to reduce the incentive to work on precisely those issues which need the most attention.  This piece focused on the tactics of a business against a professor (and a professor's enthusiasm for attacking the company) but I have little doubt the same can happen from interest groups on all sides of a debate.

More disconcerting still is what this says for the ability of science to resolve disputes about knowledge.  Whether atrazine causes abnormalities in a particular type of frog at a certain dosage should be one of those questions science can answer.  Either atrazine causes these effects or it doesn't.  This isn't one of the mysteries of the cosmos.  This isn't macroeconomics.  Yet, there are apparently findings on both sides of the issue (Note: I have't personally delved into the scientific literature on this particular matter in any detail).  Unlike some of the "science" that gets cited by the anti-GMO crowd, the work critical of atrazine has appeared in top journals like PNAS and Nature, as have articles finding no effect.  Still it appears that the biggest determinant of whether an effect was found is the prior belief about whether one exists.  I don't have a problem with Syngenta funding research on the topic (who, after all, will pay for such research?), but it is disheartening when repeated scientific experiments cannot ultimately settle a dispute that is empirical in nature.  

The last paragraph of the piece was an interesting quote from one of the professor's former students:

He had come to see science as a rigid culture, “its own club, an élite society,” Noriega said. “And Tyrone didn’t conform to the social aspects of being a scientist.” Noriega worried that the public had little understanding of the context that gives rise to scientific findings. “It is not helpful to anyone to assume that scientists are authoritative,” he said. “A good scientist spends his whole career questioning his own facts. One of the most dangerous things you can do is believe.”

In part, I agree.  But, I also fear this is part of an attempt to undermine the ability of scientific inquiry to settle empirical disputes.  I teach a graduate research methods class, and talk a bit about the definition of science, which is often described as a systematic process for discovering new knowledge.  Yes, we should question our facts.  Yes, we should question our biases (and where humans are involved, that will always be an issue).  But, I hold out hope that science can, indeed, provide knowledge for those willing to follow the evidence where it leads.  Otherwise, every issue is simply a PR battle.

 

Natural Parody

A colleague sent me a link to the following video.  I found it funny, if not misinformed at times.  The irony, of course, is that many people also believe things about organic food that also aren't true.  The organic labels causes people to ascribe all kinds of mystical properties to a food.  It is also worth pointing out that, at least for meat, "natural" can't be slapped on anything - it has to be "minimally processed", among other things, according to the USDA.  In any event - it's good for a few laughs

How Would Your State Vote on a Ballot Initiative to Ban Battery Cages and Gestation Crates?

The Journal of Agricultural and Applied Economics just published a paper I co-authored with Bailey Norwood, Katie Smithson, and Max Corbin entitled: Predicting State-Wide Votes on Ballot Initiatives to Ban Battery Cages and Gestation Crates.

Here are a couple excerpts:

Using California data to project voting behavior on a hypothetical initiative in other states can be considered a thought experiment: an abstract, hypothetical scenario providing a useful index of each state’s concern for animal welfare as determined by their demographic profiles. There are a number of states where initiatives are not allowed, yet this study can still illuminate our understanding of those states also. For example, Minnesota, North Carolina, and Iowa are the three largest hog states but do not allow initiatives—yet these industries can still be affected by legislation sponsored by politicians with a personal interest in animal welfare or politicians influenced by a particular lobby. The absence of an initiative does not mean constituents have no influence nor does it imply constituent demographics are irrelevant. Which of these state’s constituents will be the most or least accepting of gestation crate bans according to the state’s demographics? This research has an answer.

and 

The bottom line for the hog industry is this. Over three-fourths of U.S. hog production is insulated from state-level initiatives banning gestation crates. The question is whether the bad publicity from initiatives in other states and groups, combined with the relatively small benefit of gestation crates, is strong enough to induce the hog industry as a whole to voluntarily discard gestation crates. The answer to this question is unknown. What this study does show is that a state-level initiative to ban gestation crates in Massachusetts, Nevada, Utah, and Washington is a real possibility.