We are what we eat is an age-old adage that has more implications than ever in the context of modern-day science and biotechnological experimentation with the genetic makeup of the food we eat. Whether it is the highly processed corn- and soy-based products that permeate nearly everything we consume or the animals we eat that are fed the same corn-based products, the long-term effects of consuming genetically engineered (GE) or genetically modified organism (GMO) food are yet to be fully documented. (This does not include the cross-breeding of cows and goats with spiders, for instance.) Of course, mankind has been cross-breeding plants for millennia, so some ask: "What is the controversy about?"

The controversy emerges when mega-corporations (also known as big agra) such as Monsanto produce seeds that are injected with the DNA of other species to produce specific effects such as resistance to chemicals and herbicides. Beyond the self-perpetuating - some might say monopolistic - marketplace this creates (Monsanto sells the herbicide Roundup that the seeds it sells are resistant to), critics are concerned about the long-term effects to human health by tinkering with Mother Nature so much.There's a Catch-22 at work here, too. The long-term studies that would allay consumer fears are not pursued by the purveyors of the GMO products, but those same purveyors fiercely defend their intellectual-property rights so that third parties cannot publish their own independent studies done with the GMO products. If the GMO products are so wonderful, then why not open the doors wide on independent research?

Two events in the past few months raised the profile of foods with genetically modified ingredients - and also put a spotlight on how messy the issue can be.

The first was the publication in September of a study led by Gilles Eric Séralini involving the herbicide Roundup and herbicide-resistant Roundup Ready corn (technically known as NK603) - both Monsanto products. Rats in the study developed tumors, died prematurely, and suffered organ damage.

The second was the defeat in November of California Proposition 37, whose ballot summary read that it would have required the "labeling of food sold to consumers made from plants or animals with genetic material changed in specified ways."

There was a lot of heat with both events.

The Séralini study and its PR roll-out were met with an intense backlash from genetic-engineering apologists and much of the scientific community, and the European Food Safety Authority - among other scientific organizations - rejected its validity, saying it featured "inadequate design, analysis, and reporting."

In California, Prop 37 opponents - including Monsanto Company, E.I. DuPont de Nemours & Company, and the Grocery Manufacturers Association - spent more than $40 million to defeat the labeling ballot measure.

Yet combined and detached from the rhetoric and motivations on all sides, these two events neatly summarized the national and international debate over foods with genetically modified ingredients. Are they safe for human consumption? And should the government require the labeling of foods with genetically modified ingredients - the way nutrition and ingredient labels now note the presence of allergens?

Depending on whom you ask, the answer to the first question ranges from "absolutely" to "we don't know" to "absolutely not." And the answer to the second question is largely - but not wholly - determined by the answer to the first.