Nutrition experience, research, and orthodoxy, with some economics parallels

Lynne Kiesling

Last week was our spring break, and I finally took some time to read Gary Taubes’ 2008 book Good Calories, Bad Calories. Taubes is an investigative science journalist who has been writing for years about the science of nutrition and epidemiology, and the book focuses on a long, careful, detailed narrative about how such science has evolved since the mid-19th century. One of the themes that emerges is that some of the most prominent researchers, particularly those advancing the dual hypotheses that fat causes heart disease/overeating causes obesity, did not test their hypotheses for falsification using controlled trials in designing their research, and are also personally invested in doing research that “proves them right”. Thus, Taubes argues, an orthodoxy has formed around these hypotheses when he finds the scientific support for them lacking, and similarly finds support for an alternate hypothesis — refined carbohydrates cause heart disease and obesity. But the orthodoxy resists testing that alternate hypothesis.

I have personal interest in this topic based on my own experience. As a high metabolism athlete for all of my life, I grew up being able to eat almost anything in unrestricted quantities. But when I got my first faculty job out of grad school (at WIlliam & Mary, yay!) in 1992, the combination of teaching and research duties with moving to a swampy climate against which my body rebelled meant a reduction in my activity, bloating because of the humidity, and weight gain. Without really thinking about it (because I hadn’t had to before), I reduced my meat consumption and substituted into (refined and unrefined) carbs. The next two years were right out of Taubes’ book — reduction in calories to manage weight while increasing exercise, but not having enough energy to actually make it meaningful, culminating in what is now known as metabolic syndrome complete with insulin resistance, hormone imbalance, and symptoms of polycystic ovarian syndrome. I then spent two years revamping my diet to reduce refined carbs, include more animal and vegetable protein at every meal, and monitor my hormone and energy levels, and succeeded in reversing all negative symptoms. I returned to the energy levels that have enabled me to do longer and longer distance cycling and triathlon endurance events and the demanding training for them. Even though I don’t eat low-fat, my triglycerides are so low that my doctor marvels at it. Taubes’ argument is consistent with my experience.

Economist Russ Roberts has been experimenting with his diet and exercise for the past six months, following broadly the same principles that I do (including the refined carbs on the weekend), and he reported in on Friday: 20 pounds lost, more energy, feeling of satiation, low triglycerides. Again, consistent with my experience.

You may know Russ for his outstanding EconTalk podcast series, and in November 2011 he interviewed Gary Taubes. The conversation was interesting and informative, and the podcast page lists lots of resources for further reading. One theme that Russ developed in the discussion was that in both nutrition research and economics research, the issues come up of orthodoxy and structuring research questions in ways that generate falsifiable hypotheses when you are studying such a complex, dynamic system as either the human diet/cardio/endocrine system or the human economy. The human traits that incline us toward orthodoxy, whether it’s wanting to prove ourselves right or appeal to authority or some other trait, have led to models and hypotheses that are not supportable or not even meaningfully testable/falsifiable. So for me reading Taubes’ book was a good cautionary tale of the value of humility beyond the analysis of low-carb/low-fat nutrition.

Another insight that comes up in the book that I would add to Russ’ comparison with macroeconomics is heterogeneity. Taubes is careful to point out that individuals have different metabolic experiences and achieve homeostasis with different combinations of fat, carbs, etc., so while low-carb nutrition may allow some people to strike a healthy heart and weight balance, others may be able to eat more carbs and do the same. Heterogeneity means that there’s no one-size-fits-all hypothesis … and as any Austrian macroeconomist will tell you, that’s the argument they put forth about macroeconomic models and aggregation. Heterogeneity in the capital structure in reality means that models abstracting from such heterogeneity are more likely to mislead.

Tedious peak oil claims from the EU Energy Policy Blog

Michael Giberson

Not all peak oil analysis comes across as sloppy, misleading, and a bit tedious, but this one does: “Peak Oil Driving The Global Gas Shift.” Of course sloppy analysis abounds on the internet, and the best approach is usually to ignore it, but this example appears on the somewhat respectable site of the EU Energy Policy Blog.

The introduction to the article is set up as a contrast to the rosy outlook of a Citigroup report that claimed the shale gas boom was set to transform into an oil boom in North America. Not so fast, our author warns. Then, after a few “peak oil-friendly facts” picked from a subsequent US Energy Information Administration report (link), the author gives us the bad news from Iranian production:

The shrinking spare capacity of the OPEC states, of 2.5 Mbd, is almost exactly what Iran was exporting until late 2011, following a year average 2.6 Mbd in 2010, but since 2011 and for reasons only partly related to sanctions, and closer related to depletion, its oil output is falling: Iran’s net exports and export supply capacity may stand at only 2.2 Mbd today. Some sources suggest even less than that. In 1976, Iran could produce 5.75 Mbd and export far more than 4 Mbd to a world market that, at the time, consumed about 62 Mbd compared with 89.7 Mbd today. Explaining this while denying depletion and the impact of oil consumption growth in exporter countries and worldwide is mental gymnastics!

Allow me to attempt the “mental gymnastics,” which in this case seems to be the mental equivalent of sitting on a balance beam and swinging my legs: to wit, the internet search! Yielding an EIA country report on Iran and this chart:

Iranian Total Oil Production and Consumption, 1977-2010

EIA, Iranian Total Oil Production and Consumption, 1977-2010

The International Energy Agency’s numbers on Iranian oil production look much the same. Admittedly, our author is making claims about 2011, and especially about changes since 2011 (i.e. production over the first month or two this year), while the chart about only shows data through 2010. So imagine a slight drop for 2011 and a sharper drop for early 2012, perhaps like the drop seen in 2002. The IEA’s more recent analysis of Iranian oil suggests that production fell by 1.5 percent in February 2012, to the lowest rate in three years.

But can we call this a Peak Oil omen? Obviously, as the chart shows, Iranian oil production is down from the high levels of the 1970s. But, with the helpful labels inserted by the U.S. EIA “Iranian Revolution” and “Iran-Iraq War,” it is easy to see that the so-called above-ground factor of politics and war have driven the most significant swings in production. In addition, the chart makes clear that net exports (and most of the numbers cited in the paragraph quoted are net export numbers) depend on production and domestic Iranian consumption.

So far as I know, peak oil is a theory about production rate limits enforced by physical realities, not a theory about international trade. Net export data is at most suggestive. And especially when the trade data cited comes from a period of explicit trade sanctions imposed by nations who previously were significant trading partners, it seems all to easy to believe that the above-ground factors of politics are dominating the export data changes, and not the physical limits of depletion.

The author follows the Iran discussion with a wide-ranging sketch of gas market shifts, global energy policies toward renewables, and hopes for electric vehicles – the sort of view of the world you can have from reading many government reports on energy policies. Ultimately the author asserts a global move from oil, despite its high value, to natural gas, despite its lower value.

To me, the economics of the conclusion seems less than well worked out.