WASHINGTON — Even if voters passed it and the Supreme Court upheld it, would California’s Proposition 37 to label foods containing genetically-engineered ingredients have been a win?

The author of a critically-acclaimed book on food politics says not so much. In fact, Robert Paarlberg said, genetically-engineered crops make up less of the U.S. food supply than many opponents of the crops would have consumers believe.

“To a surprising extent, even in the United States, which is the world’s leading grower of genetically-engineered crops, we’ve kept our foods for direct human consumption largely free from genetically-engineered crops,” he said.

Paarlberg is the author of Food Politics: What Everyone Needs to Know and is the B.F. Johnson Professor of Political Science at Wellesley College, adjunct professor of public policy at the Harvard Kennedy School and associate at Harvard’s Weatherhead Center for International Affairs.

He spoke as part of a panel at the Farm Foundation Forum, “What the 2012 Election Means for Ag, Food and Rural Policy.”

Paarlberg noted that the latest attempt to label foods containing genetically-engineered ingredients joins a previous measure that failed in Oregon.

“Because this measure failed, however, the U.S. will still have no labeling requirements for genetically-engineered foods anywhere in contrast to between 30 to 50 countries abroad that have adopted labeling requirements,” he said.

But what foods actually would have been labeled? Paarlberg said that while many foods contain some type of ingredients from genetically-engineered crops, the amount of genetically-engineered foods on the market isn’t large.

“What I find remarkable, thinking about it, is the extent to which genetically-engineered foods have already been driven out of the market even without any requirement for mandatory labels,” he said.

He noted that the bulk of genetically-engineered crops are not grown for direct human consumption.

“Our big three genetically-engineered crops are not crops for primarily human food use. They are soy, corn and cotton, and 98 percent of our soybean crop goes for animal feed, 88 percent of our corn crop goes for animal feed or it’s processed for ethanol and, of course, cotton is primarily an industrial crop,” he said.

Paarlberg said that staple human foods in the U.S. aren’t part of the genetically-engineered lineup.

“As for our food crops in the United States, like wheat, rice and potatoes, we have voluntarily decided not to plant genetically-engineered varieties of these crops — no wheat, no rice. We planted genetically-engineered potatoes in the late 1990s, but that crop was withdrawn from commercial cultivation when fast-food chains told their suppliers they didn’t want to be accused of selling genetically-engineered French fries,” he said.

“As for fruits, the only genetically engineered fruit crop we grow now is papaya on about 1,000 acres in Hawaii. As for vegetables, we used to grow genetically-engineered tomatoes on 25,000 acres back in the late 1990s, but that was withdrawn, once again, in response to consumer anxieties. Now, we produce just a little bit of genetically engineered zucchini and summer squash,” he added.

Paarlberg pointed out that the animal products that come from livestock consuming genetically-engineered crops — such as meat, milk and eggs — are not labeled as GE products in countries that currently require GE labeling.

The target of legislation such as Proposition 37 are the processed foods that contain ingredients made from GE crops.

“It’s often noted that 70 percent of purchased packaged foods in the U.S. have some genetically-engineered ingredients, and that’s true, but these ingredients are mostly byproducts like oils or starch or sweeteners from genetically-engineered crops like soybeans or corn,” Paarlberg said.

He added that some groups promoting Proposition 37 didn’t have consumer choice and education as a top priority.

“If it had passed and not been struck down, food companies in the United States that were worried about adverse consumer reactions to a genetically-engineered label might have voluntarily begun reformulating their products away from genetically-engineered ingredients in order to avoid the stigmatizing label,” he said.

“This was the intent actually of some proponents of Prop 37. It wasn’t to give consumers a choice between genetically engineered and non genetically engineered foods — it was to drive genetically-engineered foods out of the market completely.”

Paarlberg said that while early worries are understandable, repeated use without any impacts should be alleviating the concerns and suspicions of GE crop opponents.

“I can understand the anxieties that activists felt 18 years ago when these crops were first placed on the market. But now, nearly two decades after a history of safe use, you would think that the advocates against this technology would start to adjust their perspective, and yet they have not,” he said.

Paarlberg also pointed out the risk to the rest of the world and especially developing nations and areas of the world with high rates of hunger and malnutrition to reducing or eliminating GE crops and GE research.

“The reason this is important is if it becomes a new norm even in the U.S. to accept this technology for industrial use and for feed use, but only marginally for direct human consumption, that will drive research money away from improving food crops with genetic engineering,” he said.

“It will reinforce tendencies in other countries to use mandatory labels and regulatory restrictions to keep genetically engineered food crops out of the market, and that will make it a needlessly more difficult task of feeding 9 billion people around the world by 2050.”

Paarlberg also warned on the dangers of not promoting GE crops for human consumption in the U.S. itself.

“If the U.S. drifts into a posture of not using genetically engineered foods in its own food crop sector, that will make it more difficult to communicate to other countries that this is an option that is available to them and one in which they should take an interest,” he said.

Moving to the topic at hand, the farm bill, Paarlberg agreed with the panelist who spoke before him, Ferd Hoefner, policy director for the National Sustainable Agriculture Coalition.

Hoefner said that to maintain the political importance of the farm bill, keeping the nutrition titles, including SNAP, as part of the bill is essential.

“I’d like to agree with Ferd. Keeping the nutrition programs in the farm bill is politically essential to the survival of farm programs as we’ve known them,” Paarlberg said.