Mark Bittman on food and all things related.

IT’S not an exaggeration to say that almost everyone wants to see the labeling of genetically engineered materials contained in their food products. And on Nov. 6, in what’s unquestionably among the most important non-national votes this year, Californians will have the opportunity to make that happen — at least in theory — by weighing in on Proposition 37.

Prop 37’s language is clear on two points: it would require “labeling on raw or processed food offered for sale to consumers if made from plants or animals with genetic material changed in specified ways.” And it would prohibit marketing “such food, or other processed food, as ‘natural.’ ” (For now, let’s ignore the vast implications of the phrase “or other processed food,” lest we become overexcited, except to say that the literal interpretation of that sentence has the processed food manufacturers’ collective hair on fire.)

Polls show Prop 37 to be overwhelmingly popular: roughly 65 percent for to 20 percent against, with 15 percent undecided. Nationally, on the broader issue of labeling, in answer to the question of whether the Food and Drug Administration should require that “foods which have been genetically engineered or containing genetically engineered ingredients be labeled to indicate that,” a whopping 91 percent of voters say yes and 5 percent say no. This is as nonpartisan as an issue gets, and the polls haven’t changed much in the last couple of years.

Unsurprisingly, Big Food in general — and particularly companies like Monsanto that produce genetically engineered seeds and the ultraprofitable herbicides, pesticides and other materials that in theory make those seeds especially productive — have already thrown tens of millions of dollars into defeating Prop 37. On the other side is a relatively underfunded coalition led by California Right to Know, which collected the necessary million-plus (yes!) signatures to get the proposition on the ballot. Although television advertising has just begun and its advocates would never say so, at the moment the bill seems assured of passage. Excellent.

This doesn’t mean labeling will begin on Nov. 7; there will be battles upon battles before implementation. But in general, as California goes, so goes the nation. (In a very real way, the history of reducing air pollution in the United States is a history of California’s pushing and the rest of the country’s adapting. As recently as 2009, California’s standards on vehicle emissions spurred the Obama administration to dramatically strengthen federal standards for gas mileage.)

The best guess about what will happen if California requires labeling of foods containing genetically modified organisms (G.M.O.’s) — which, as far as I can tell, includes almost all processed food containing corn or soybeans, the vast majority of which are produced from genetically engineered (G.E.) seeds, as well as a number of “unprocessed” foods, like an apple that won’t turn brown when sliced and a fast-growing salmon — is that food manufacturers will instead reformulate their products using non-G.E. ingredients. (By most estimates, there’s enough non-G.E. corn and soybeans to continue producing hyperprocessed food at our current alarming rate.)

FOR manufacturers, that’s a much safer bet than labeling, which they’re inclined to resist anyway and which could have a negative effect on sales. And since it’s unlikely that they’ll reformulate foods solely for California, whose population is 12 percent of the nation’s, in a way, Prop 37 is a national vote.

If you’re Monsanto, this is a big deal.

But should the rest of us care? Definitely, but perhaps not for the most obvious reasons. If genetic engineering were to prove its advocates’ oft-stated claim that only by relying upon it can we “feed the world,” labeling would be irrelevant. No one minds that vitamin enrichments — generally seen as beneficial but not exactly “natural” — are labeled, and it hasn’t slowed their use at all.

If a decline in profitability of G.M.O.’s were to lead to a greater focus on research in all fields of agriculture, that would be a plus. One could also argue that if G.M.O.’s were to become less profitable, their producers would be more cooperative with others in the field. You cannot, for example, analyze or research genetically modified seeds without express permission from their creator. Bear in mind that Europe ’s agriculture system runs nearly as, er, “well” as ours does, and without much in the way of G.M.O.’s.

G.M.O.’s, to date, have neither become a panacea — far from it — nor created Frankenfoods, though by most estimates the evidence is far more damning than it is supportive.

But that’s not the issue. Prop 37 isn’t a ban on foods containing genetically engineered material; it’s a right-to-know law. As things stand, you can find out whether your salmon is wild or farm-raised, and where it’s from, but under existing legislation you won’t be able to find out whether it contains the gene of an eel.

That has to change. We have a right to know what’s in the food we eat and a right to know how it’s produced. This is true even if food containing or produced using G.M.O.’s were the greatest thing since crusty bread. (It’s worth mentioning that as a candidate, Barack Obama promised to label genetically engineered food; maybe a re-elected Obama could work on that.)

Big Food is worried that this is the thin edge of the wedge, and I hope they’re right. If we win the right to know what’s in processed food, we might be inclined to demand to know how other food is produced. (You might think of Prop 37 as the anti-ag-gag law.) If genetically engineered food is so terrific, persuade us; if it’s not, well, fine. In any case, it should be up to us to buy it or not, but first we have to know what it is.

I want to know — quite technically, in all the detail available — how my food is produced, and I’m far from alone. We’d be able to make saner choices, and those choices would greatly affect Big Food’s ability to freely use genetically manipulated materials, an almost unlimited assortment of drugs and inhumane and environmentally destructive animal-production methods.

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