Major science group weighs in on safety of genetically modified foods

Corn, potatoes, apples, soybeans... about 80 percent of the food in America's grocery stores is genetically modified, and a new report from a leading science organization finds it's generally safe for humans and the environment.

The National Academies of Science, Engineering and Medicine concluded Tuesday that tinkering with the genetics of what we eat -- adding a gene from another species -- doesn't produce the "Frankenfood" monster some opponents claim it does. But it isn't feeding the world with substantially increased yields, as proponents predicted.

The 408-page report was two years in the making and included a review by 20 experts of more than 900 studies. It received more than 700 public comments, as well.

The authors conclude that there's "no substantiated evidence that foods from GE [genetically engineered] crops were less safe than foods from non-GE crops," and that regulators need to make their safety focus more on the end-product of the food that's made rather than the nuts and bolts of how it's made.

The report also found that when farms switched from conventional crops to the engineered varieties, there was no substantial change in their yield. Production in general is increasing in agriculture, but U.S. Department of Agriculture data don't show that genetically engineered crops are increasing at a higher rate, despite experimental results suggest that they should, the report said.

Both supporters and detractors of genetically modified foods "claimed victory," said CBS News medical contributor Dr. David Agus.

"People who were against GMOs are very happy because it said GMO crops didn't increase yields, which was the whole premise of doing that. And obviously, the GMO companies said they're not harming health," Agus said on "CBS This Morning."

While the report said there's no evidence of environmental problems caused by genetically modified crops, pesticide resistance is a problem. Farms that use genetically modified crops in general are helped, but it may be a different story for smaller farmers and in poorer areas of the world.

Most of the modified plants are soybean, cotton, corn and canola, and in most cases, genetic tinkering has made them resistant to certain herbicides and insects.

"Farmers in general are gaining," with less pesticide use and a bit higher yield, academy committee chairman Fred Gould said at a Tuesday news conference.

The report waltzed a bit around the hot political issue of whether or not genetically modified food should be labeled. The study's authors said labels aren't needed for food safety reasons but potentially could be justified for the sake of transparency and social and cultural factors - along the lines of "Made in America" labels. That stance was praised by some environmental and consumer groups, but criticized by some scientists as unnecessary because the food poses no unique risks.

"Transparency is key," said Agus. "All of us have a right to eat whatever we want ... at the same time, if we're going to learn from it and say what food affects me, I need to know what's in it," he added.

The nuanced report also said it is important not to make sweeping statements on genetically engineered foods.

The National Academy, established by President Abraham Lincoln to provide scientific advice, has issued reports before saying it could find no safety problem with eating genetically modified food. But Gould, of North Carolina State University, said this report is different because his study team started by listening to critics of such foods and examined anew hundreds of studies.

"To some extent we know more about some genetically engineered food than we do about other food," committee member Dominique Brossard of the University of Wisconsin said. "There are limits to what can be known about any food. That's something we're not used to hearing as consumers."

Many scientists who work on the issue but weren't part of the study team lauded the report as sensible, but not surprising. Mark Sorrells, a fellow at Cornell's Atkinson Center for a Sustainable Future, said the report is "very well balanced, accurate, and reiterates much of what has already been published many times."

"Science is science, facts are facts," said Bruce Chassy, an emeritus professor of biochemistry and food science at the University of Illinois, in an email. "There's just no sound basis for their opposition just as there was never any scientific basis to believe GM plants should be viewed any differently than any other."

One dissenter was Charles Benbrook, who used to be at Washington State University but is now a private consultant. He said he feels the risks of genetically engineered food are more serious than more mainstream scientists think they are, and that the human health assessments aren't ample enough.

Some groups critical of genetically engineered foods criticized the report before it came out. Food & Water Watch said the National Academy is taking funding from biotechnology firms and using "pro-GMO scientists" to write its reports.

The report was funded by the Burroughs Wellcome Fund, the Gordon and Betty Moore Foundation, the New Venture Fund, the U.S. Department of Agriculture and the academy -- none of which have direct connections to the agricultural biotechnology industry. It was peer reviewed by outside experts and committee members are vetted for financial conflicts of interests, said academy spokesperson William Kearney.

As for the corporate side, Eric Sachs of Monsanto Scientific Affairs, said, "After 30 year of research and assessments, the science and safety behind GE crops has been well-established and strongly supported by the scientific community..."

Still, Agus said Monsanto's original premise that genetically modified crops would increase yield dramatically and reduce worldwide hunger has yet to be proven. "We haven't seen that data yet," Agus said.

Unlike many scientists, Marion Nestle of New York University, who was a reviewer but not a report author, said, "The report reveals how little is known about the effects of GE foods."

If the people behind the report want to end the polarization over these foods, Nestle said, "This won't do the trick."