Sunday, February 04, 2007

Rising above our diet...

Good authors can persuade beyond the power of their ideas. Michael Pollan is one of them. In his previous books, notably The Botany of Desire and The Omnivore's Dilemma, he attracts readers with simplicity and a slathering of good old common sense. He is especially suspicious of anything that hints at "science".

His latest polemic against what passes for nutritional science advances his earlier misgivings to full-blown food-Darwinism:
Note that these ecological relationships are between eaters and whole foods, not nutrients. Even though the foods in question eventually get broken down in our bodies into simple nutrients, as corn is reduced to simple sugars, the qualities of the whole food are not unimportant — they govern such things as the speed at which the sugars will be released and absorbed, which we’re coming to see as critical to insulin metabolism. Put another way, our bodies have a longstanding and sustainable relationship to corn that we do not have to high-fructose corn syrup. Such a relationship with corn syrup might develop someday (as people evolve superhuman insulin systems to cope with regular floods of fructose and glucose), but for now the relationship leads to ill health because our bodies don’t know how to handle these biological novelties. In much the same way, human bodies that can cope with chewing coca leaves — a longstanding relationship between native people and the coca plant in South America — cannot cope with cocaine or crack, even though the same “active ingredients” are present in all three. Reductionism as a way of understanding food or drugs may be harmless, even necessary, but reductionism in practice can lead to problems. [More]

Pollan is a leading voice in the "we used to eat better" school of nutrition. Over the years he has graduated from mere wariness of the food industry to sincere opposition. It all seems so logical in his witty prose.

Not all of us are buying his extrapolated conclusions.
But Pollan's nutritional Darwinism only makes sense if the selection pressures of the distant past were in perfect alignment with the health concerns of today. In other words, our food culture would have evolved to protect us from cancer, heart disease, and obesity only if those maladies had been a primary threat to reproduction in the ancient world. It's hard to imagine that the risks posed by these so-called "diseases of affluence"—which often strike late in life, after we've had babies—would have been as significant to our fast-living, sickly forebears as the dangers of, say, bacterial infections or the occasional drought. Indeed, for much of human history, natural selection might well have traded off the dangers of morbid obesity to mitigate the risk of starvation. There's just no way to know how the ancient culinary traditions will fare in the modern world until we try them. [More]
It astounds me that with every leap of technological empowerment, the effort to redraw the past springs up anew. "Our food was better when we killed the chickens in our own backyards." old-foodies wail. That subjective judgment is hard to counter, but we do know it was more dangerous. That small problem food science did handle well.

I do not argue our food and nutrition are as good as they can be. In fact, thanks to critics like Pollan, pressure is mounting for our food industry (of which agriculture is a small part, not the other way round, incidentally) to turn its efforts to applying the results pouring out of research institutions. Our foods must address what we now know to be true about both our bodies and our diet.

There is room in America especially to allow wide experimentation to find the answer to this question. But my money is on technology.

4 comments:

brian said...

John,

Evolution, at least in its popular version, is a most plastic scientific concept, and thus lends itself to almost any theory that one can come up with regarding human nature. And so lots of scientific amateurs use it to justify their pet theory on human behavior, human brains, bodies, society, etc. How so many people can speak with such authority about the history of the last 200,000 years, and mold it to their own notions, is beyond me.

Of course, the ability to imagine historical scenarios that provide meaning to current situations had survival value for our ancestors when they were confronted with .... Oh never mind.

Brian

John Phipps said...

brian: One thing is changing in this debate. As we witness the actual physical changes in the brain while we think we can at least match up instinctive and logical responses with real-world stimuli.

Back-fitting data may become less of a tool in the future as we seek to understand why we act as we do.

Bill Harshaw said...

Pollan is tremendously frustrating to me. He writes so well that I halfway agree with his ideas. But then I remember my sainted mother's cooking (somewhat like Bill Bryson's mother in his most recent book) and compare the supermarket's selection today with what it was in the 1950's and think, no, he can't be all right.

John Phipps said...

Bill:

The dude can write, but he is also pretty naive when it comes to economics. In Omnivore, for example, he quotes at length an Iowa farmer who explains the quandry of farmers and prices.

When prices drop, they assert, farmers have to produce more to keep their income steady. This leads to more supply and even lower prices, which is why (unlike all other businesses) farmers need government to control production.

The howling illogic of this preposterous legend is never questioned by Pollan. For instance, with corn at $4 shouldn't farmers be cutting back on production? And how pray tell can you produce more corn at $2 that you could at $3?

The truth is we produce as much as we can with the economic constraints we have - all the time. And we can't produce more just by "spraying and eroding".

Overlooking the stunning errors in his economics diminishes for me his charmingly seductive social commentary.

But again, the man can write. He just can't farm.