In defense of corn

In The Omnivore’s Dilemma, Michael Pollan tells us:

Read the ingredients on the label of any processed food and, provided you know the chemical names it travels under, corn is what you will find. For modified or unmodified starch, for glucose syrup and maltodextrin, for crystalline fructose and ascorbic acid, for lecithin and dextrose, lactic acid and lysine, for maltose and HFCS, for MSG and polyols, for the caramel color and xanthan gum, read: corn. Corn is in the coffee whitener and Cheez Whiz, the frozen yogurt and TV dinner, the canned fruit and ketchup and candies, the soups and snacks and cake mixes, the frosting and gravy and frozen waffles, the syrups and hot sauces, the mayonnaise and mustard, the hot dogs and the bologna, the margarine and shortening, the salad dressings and the relishes and even the vitamins. (Yes, it’s in the Twinkie, too.) There are some forty-five thousand items in the average American supermarket and more than a quarter of them now contain corn. This goes for the nonfood items as well: Everything from the toothpaste and cosmetics to the disposable diapers, trash bags, cleansers, charcoal briquettes, matches, and batteries, right down to the shine on the cover of the magazine that catches your eye by the checkout: corn. Even in Produce on a day when there’s ostensibly no corn for sale you’ll nevertheless find plenty of corn: in the vegetable wax that gives the cucumbers their sheen, in the pesticide responsible for the produce’s perfection, even in the coating on the cardboard it was shipped in. Indeed, the supermarket itself—the wallboard and joint compound, the linoleum and fiberglass and adhesives out of which the building itself has been built—is in no small measure a manifestation of corn.

The full text of this chapter may conveniently be found at Pollan’s website. I do recommend reading the whole thing; while preachy, it is a useful overview of the commercial food system. I highly recommend Twinkie, Deconstructed by Steve Ettlinger as a Discovery Channel type exploration of industrial food accompaniment to Pollan’s work.

Before I get jumped on for supporting the “agricultural-industrial complex”, let me say that I wholeheartedly agree with Pollan’s recent mantra “Eat food. Not too much. Mostly plants.” I just think all of the anti-processed food (anti-corn) hoopla is a bit misdirected. The producers of processed food are simply producing what consumers demand, with assistance from commodity subsidies. Instead of making books and movies aimed at the food elite, it would be far more useful to change subsidies to make healthy food more affordable at the same time as making processed food and animal products more expensive. This would change demand by default, but a public awareness campaign to make healthy food more interesting for people who aren’t currently eating it would be a great accompaniment to the changes in pricing.

Now, back to corn… By Pollan’s reckoning, 11,250 products contain corn. His estimate of 25% has recently been ratcheted up to 90% for the debut of Food, Inc. by filmmaker Robert Kenner in a PBS interview (this new number is what inspired this post). Despite the boasts by the National Corn Growers Association and the Iowa Corn Promotion Board that “thousands of products in the supermarket contain corn” (4000 products according to Iowa Corn’s FAQs), the reality is that the amount of “corn” in the grand majority of those products is minimal. Think about what processed foods are actually made of… wheat! Cookies, crackers, waffles, bread, cereals, pasta… wheat is the 1st ingredient in a far higher percentage of processed foods than is corn, and actually makes up a far greater percentage of the products by weight. Aside from a few obviously corny products like corn chips and grits, the “corn” in most products is actually highly purified compounds that make up a tiny fraction of the total ingredients.

Composition of #2 yellow dent corn. Adapted from Plymouth Oil.Corn is used to produce hundreds of useful compounds, some of which Pollan lists in the quote above. Corn is both whole food and raw material due to its composition – parts oil, starch, and protein all have their uses. We haven’t even touched the potential of corn. Right now, the public (including me) is demanding biodegradable plant sourced alternatives to to petroleum products. Today, we can buy cleaning products, bath and body products, and even plastics that were made in part with corn. Some of the corn-derived compounds have allowed food manufacturers to produce “foods” that should never have existed, but I don’t think we can blame corn for Twinkies – they would have been made regardless with sugar and ingredients from other sources. Other foods produced with corn-derived ingredients have become staples. Corn derived ingredients allow for smoother pouring, reduced caking, increased stability and solubility, and tons of other useful properties.

True, some of (if not all of) the foods in the center of the supermarket could be made from scratch at home, but this isn’t realistic for most of us. Some degree of convenience is important in households where all of the adults work outside of the home, whether we like it or not. Corn based sweeteners have been demonized as the cause of obesity and diabetes, but we would have seen the same increase in both health problems if people consumed equal amounts of sugar. The health risks of HFCS in particular were debunked in a critical review that reinforced the idea that the problem is an increase in total calorie intake combined with not enough exercise. An interesting tidbit: honey has a fructose/glucose ratio of 50/44 while the two types of HFCS are 42/53 and 55/41 (Wikipedia).

Uses of Corn. Posted at Policy Economist.As I’ve mentioned in plenty of other posts, there is certainly a negative environmental impact from the way we have been growing corn, but the amount of the total corn crop that goes into making all of these raw materials is fairly small. According to the USDA,  there were 12 billion bushels of corn harvested in 2006. The grand majority of the harvest goes to feed, fuel, and exports (most of the exports are used as feed as well). Only 1.4 billion bushels were used in food.  Any complaints about corn should be leveled squarely at grain-fed meat.

Finally, some worry that having corn derivatives in so many products contributes to allergies. This doesn’t really make sense to me, because so many of the derivatives are purified products. As I understand it, corn-derived citric acid won’t set off an allergic reaction in someone who is allergic to corn because the corn antigens have been purified out of the citric acid. Whether it is extracted from corn or any other plant source or synthesized chemically, citric acid is citric acid. It seems that the potential allergenicity of a corn derivative depends on how pure it is. That’s all I’ll say about the subject because I do not have enough education in the workings of the incredibly complex human immune system. If you have any experience in the subject, please elaborate in a comment.