Tuesday, April 09, 2013

Who's Rational?

Salt Sugar Fat: How the Food Giants Hooked Us by Michael Moss provides an overwhelming insight: big food companies know much more about how humans choose food than anyone else (including academics). If any people still think that humans "intuitively" or "instinctively" choose to eat the foods that their bodies actually "need" -- they should read Salt Sugar Fat! Potato chips and soda aren't nature's most perfect foods, but they are carefully designed with the purpose of meeting a human's strongest cravings for (yes) salt, fat, and sugar. So are lots of other processed foods. Broccoli, we just aren't that into you. Our instincts stink. It's a good read with lots of data.

I was thinking about several other books with coordinating insights about the issue of how humans choose what to eat, and how unlikely it is that our instinctive choices can help us achieve healthy lives, desirable body weight, and avoidance of nutritional maladies like diabetes. Also how hard it is to achieve these ends through rational self-control. Or government intervention. Or medical treatment.

First, I thought about a book that's really not about food at all: Thinking, Fast and Slow by Daniel Kahneman. Decision making in the many humans the author has observed is far from the calm rational process that many people believe in -- especially diet prescribers! The last thing you heard, a major event that impressed you, or someone who was manipulating you have a much higher impact on your conclusions than you would prefer to believe. Overlay this with the evidence of direct manipulation of your love of certain flavors in Salt Sugar Fat. OOPS.

Next, a very frequently quoted book: Mindless Eating by Brian Wansink PhD. As I read it a few years ago, I constantly thought about how the food industry had already learned what Wansink's research revealed. They kept their insights mainly secret and used their knowledge to make people eat more. In contrast Wansink presented his research studies as a set of insights that could help one create a strategy to eat less. Yes, we suck up more calories if there's a huge bowl of M&Ms than if there's a smaller one. We'll eat much more from a self-refilling bowl of soup because our eyes are fooling us. If someone takes away the piles of bones, people will eat more chicken wings because they lose track of what they are doing. Wansink's experiments are cited (often out of context) frequently, but reading the book really shows you how little control you have even when you think you're paying attention.

The book Why Some Like it Hot by Gary Paul Nabhan is about evolution (though not going all the way back to our prehistoric ancestors and not particularly applicable to most urban westerners). He discusses traditional foods in some relatively isolated areas where the native people over time adapted to the available food supplies, and he describes how a change, usually a forced change, to a western and modern diet has harmed them, especially by causing obesity and diabetes. Among others, he explores the foods of the eastern Mediterranean island of Crete, Native American foods in parts of the southwestern US, and native foods of Hawaii. He describes some efforts where people have reintroduced foods of their recent ancestors. His research theme: "how food reflects the interaction between biological and cultural diversity." (p. 2)

The Omnivore's Dilemma by Michael Pollan tackles similar themes from a different angle. His exploration of what the term "organic" has meant at various times offers an alternative view of what people think they are doing when they think they are rational.

Science applied to nutrition is not new. Perfection Salad by Laura Shapiro describes the well-meaning but often misguided efforts of the late 19th and early 20th century women to create the new discipline that they titled "home economics." Shapiro illustrates how their efforts paved the way for mass-produced and highly processed foods to be accepted into the American diet, and how the longest-lasting achievement was pathetic "home-ec" classes that may recently have at last disappeared from junior high schools. (I sure remember Miss Gordon, our home-ec teacher!) These well-meaning advocates of scientific nutrition 100 years ago or so also tried to change lower class eating habits in American cities, especially among the very poor and immigrant communities, but people preferred to eat what they liked, not what someone told them was good for them. One amusing thing: how the same type of reasoning is going on now, and probably has never stopped since the era covered by the book.

When I read libertarian arguments about the freedom to choose whether to drink a 32 ounce soda or not, I wonder about the rationality of the writer. When I read about people who think they are on a "paleolithic" diet because their food choices become so rational and evolutionarily sensible, I suspect that they don't know about actual food history. Same for the fad for "intuitive eating" and a number of other claims about how our bodies can guide us to health. (Against Autonomy: Justifying Coercive Paternalism by Sarah Conly as reviewed here sounds as if it has a lot of relevant material, but I haven't read it yet.)

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